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Top of Web PageDISCLAIMER:
The modifications described in the following text
are for educational purposes only. In no way do I recommend that you apply these
modifications to your own motorcycle. If you do choose to go ahead and modify
your motorcycle based on the information in this document you will accept all
responsibility for your own actions. The author(s) of this FAQ and host(s)
providing it for you accept no responsibility whatsoever. If you are unqualified
to make any of the changes described herein but are bent on doing the
modification, seek out a knowledgeable friend or professional mechanic for
assistance.
General
Pre-Y2K (white) models including differences
between Open Enduro and Raid models
Y2K (blue) models*Revised
September 2006
What's a TTR worth?
What should I look out
for when buying a TTR?
Uncorking the TTR250
* Revised June 2007
Fuel tank options for blue TTR250s
* NEW
January 2007
Dating a TTR from its frame number
Chain & sprocket information*Revised
March 2008
Handlebars and levers
*Revised October 2006
Can I convert the digital speedo from kph to mph?*Revised
August 2004
More speedo information*Revised
February 2008
What tyres and tubes are best for on and off road use?March 2008
Can I get a big-bore kit for
the TTR?*Revised
June 2007
Can
I fit an oil cooler?
Can I get a bigger tank for
Desert Rallies etc?
Improving the
headlight, cheap replacement bulb option and installing an on/off switch.
* Revised July 2005
Can I get second-hand parts for my TTR?
Can I modify the exhaust to improve power?*Revised
July 2005
Carburettor setup, jets & needles
+ problems arising after storage*Revised
March 2008
What brake pads fit? *Revised
April 2008
Fitting rear pads
Oil changing* Revised June 2007
Can I get a bash plate and frame guards for my TTR?* Revised
December 2007
Need a grab handle for your
blue TTR?
* New December 2005
Batteries
Kick-start kits
* Revised August 2006
Starter motors
* Revised November 2005
Replacing
the one-way starter bearing or sprag clutch
* Revised June 2007
Clutch plate information
Fork Seal and head stem bearing inspection or
replacement* Revised June 2007
Spark Plugs
How can I lower the TTR250?
Where can I get a manual?*Revised
September 2006
Wheel bearings and seal details
* Revised March 2008
Clutch inhibitor switch replacement
and other safety switches* Revised June 2007
Rear shock absorber, suspension sag adjustment & linkage
repairs
* Revised March 2008
Installing a Scott's Steering Damper on a '99
Clogging of front sprocket
on white TTRs
Smarten up your TTR! *Revised
January 2008
TTR250 - Street Legal in
California?
Got a brand new TTR?*Revised
March 2005
When it all goes wrong?
Front wheel compatibility
Specification comparisons
Further TTR links
*REVISED March 2008
Advertising web
pages - Australia, UK, USA and France
A little extra pressie at Xmas?
General: The TTR250 has an air-cooled, 4 stroke, 4 valve, DOHC single with
electric start, six (fairly close ratio) speed gearbox and disc brakes front and rear.
Owners tend to be very enthusiastic about the model and justifiably so. I am one
such enthusiast and when I first got my TTR I struggled to find any information
on it - hence this FAQ developed. I am now on my third TTR (a new 2004 model) and still
think they are the best all-round trail bike around!
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Pre-Y2K (white) models. There are basically two models: the Open Enduro and
the Raid. The TTR is a very
civilised traillie that the UK Trail Bike and Enduro Magazine (TBM) described as being "as civilised as it is
competent". Only a handful of TTRs was imported into the UK back in 1995 by
Mitsui Yamaha and were never classed as "official" imports. They seem not to have sold well - not because they weren't good bikes -
but because of what was described as an "exorbitant" price tag at the
time of £4,000 plus.
There seemed to be a lot of imports between 93 and 95 (usually white plastics
and metal tanks) after which there seems to be a gap until the new
"blue" TTR (plastic tanks) became available and sold officially by
Yamaha in the UK. Some
of the common parts are interchangeable with other makes of offroaders, e.g. brake pads, but
the gel battery is peculiar to the TTR (and expensive). The Open Enduro model
has a well specified suspension set-up with adjustable
units front and rear. The very capable quick-steering front end has a
leading axle and air-damped forks with over 10" of travel. The rear has Yamaha's
own rising rate monoshock with a remote reservoir that allows adjustment for
both compression and rebound damping and about 10" of travel as for the
front forks. It has a steel box section frame with a heavy duty ally swing arm
and distinctive purple anodised wheel rims which you either love or hate! The
engine thrives on revs but has enough bottom end to plonk along at low revs and
still pull cleanly from nothing. Quoted at 28bhp @ 8,500rpm
The
differences between the Raid and Open Enduro models:
·
the tank is larger on the Raid hence if you fill
it right up its going to add weight over and above that of the OE
·
the headlight assembly on the Raid is more
suitable for road or use on night trials but it is a fairly hefty (4lbs weight
compared to 1lb 4oz of the OE plastic unit) item with a mild steel protection bar
·
the Raid doesn't have adjustable rear compression
damping i.e. "Hard-Soft" clicker adjustment on the rear shock "reservoir whereas
most OEs have them
·
the Raid’s side panels are more like “pods” -
there is a useful plastic box under the left hand one containing the tool kit
·
chain size and gearing is different with a 520 on
the Open Enduro and a 428 on the Raid
·
the rear sub frame is also different as are the
seat layouts – the Raid seat is lower (about 35” off the ground compared to the
OE’s 36.25”) and flatter. It’s designed for more sat down, long distance work
but is a lot better than the OE if you want to carry a passenger
·
rear footpegs on the Raid are mounted separately
onto the sub frame and on the Open Enduro are small alloy ones mounted direct to
the subframe.
·
Spec. for OE
is on this FAQ – spec. for the Raid is available at:
www.pettefar.com/ttr/spex.html
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Y2K (blue) models.
Since about 2000 all new TTRs have had blue "YZ" plastics and plastic tanks.
They are based on the Open Enduro version rather than the Raid. The front
forks have air valves for adjusting the spring rate and a damping adjusting
screw for adjusting the damping force. The rear shock has the usual spring
reload adjustment, rebound damping force adjusting dial and a compression
damping force adjusting knob.
The models sold in Europe have electric and kick start
as standard making them
"dual start" as well as having revised (quicker) steering geometry and suspension.
The TTRs that are supplied to the USA are ONLY electric start - the
GYTR kick start kit is available as an extra.
Click here for details of US 2006 model.
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How much should I pay for a TTR250?
In the UK, older "white" TTRs resell for between £1,200-2,000 with blue models
£2,000 upwards. The Open Enduro model are more sought after than the Raid and
hence fetch a higher price. Expect to pay about £3,195 (March 2005) in the UK -
list price £4,399 as at March 2005 - on the road. The TTR250 is an "official" import into the USA and
Australia/NZ hence can be bought at any Yamaha dealer I guess.
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Uncorking
the TTR250
Two freebie mods to start with:
1. Look under the tank at your throttle linkage and you will notice that Mr
Yamaha installs a stop screw that limits you to less than full throttle. Adjust
the screw to allow full travel of the throttle linkage but to stop it just
before the throttle slide hits the top of the carb. Some riders take the screw
completely out but I wouldn't recommend that.
2. If you haven't got a US model, remove the exhaust restrictor in the
rear of the header pipe - details farther down. If you have got a US
model, remove the screw at the end of the exhaust and pull out the baffle but
don't do this if you ride where there are spark arrestor laws. Both of these
will allow your bike to breathe a little better.
The next will cost you a small amount:
1. Replace the stock filter with an aftermarket filter like Uni or Twin Air.
2. Pull the rubber snorkel out of the top of the air box ONLY if you don't ride
through deep water! Some owners recommend just trimming the snorkel by cutting
it back one rung at the top and two rungs in the air box itself.
3. Rejet the bike to suit.
4. Replace the standard front sprocket with a 13 tooth one - this will improve
the TTR's acceleration and off-road capabilities greatly without hampering top
speed overmuch.
Performance gains will be obvious. The thing you will notice most is that the
engine will accelerate quicker. If you ride at high altitude, and don't have
water crossings to worry about, then, in addition to removing the snorkel, you
may consider cutting holes in the top of the air box but just make sure you
rejet to suit.
The next will cost you a lot more:
Replace the standard silencer with an aftermarket one. This adds power and gives
a significant weight saving. If trail riding in the UK (or any other sensitive
area in the world) please make sure your replacement is a quiet one! We don't
want to lose our trails and green lanes just to gain a bit of power and sound
cool.
See this excellent thread by Aaron Cooper from the ThumperTalk forum which
explains it all in more detail and with pics:
http://www.thumpertalk.com/forum/sh...1&highlight=250
STOP PRESS - Aaron updated his "sticky" on ThumperTalk
on 25 June 2007 with new links for the jets etc. Thanks Aaron - it is a
super-helpful resource for TTR250 owners looking for a bit more power.
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Fuel tank options for blue TTR250s
Many thanks to Al Moore for
the information!
-
Acerbis 22lt TTR250 model - but
very rare.
-
Nomad rear tank options, 4.5lt
up to 8lt.
-
Custom fitting of the Honda
XR250/400 and or 600/650 after-market tanks.
-
Acerbis / IMS / Clarke -
Safari Tanks
supply these tanks in sizes from 17lt up (some cases there is a 40lt that
may fit)
Nomad “bum” tank 8lt. Good points -
to have a separate fuel supply if the bike has a big fall crash etc. Bad points
- it removes the option for a pillion, pilot cannot slide back to the rear of
the seat on the longer road rides, and or rear rack, adds weight over the rear
sub frame and raises the centre of gravity as well as weighting the left side of
the bike (not to noticeable)
17lt (Honda XR250/400) IMS tank.
Good points - an extra 7+ lts of fuel, tank is not too wide so does not change
the feel of the bike to much. Bad points - needs to have fair bit of mucking
about to get the bolts at the front to line up, and seat needs to be reshaped to
fit up neat.
23lt (Honda XR650) Acerbis made
tank. Good points - loads of fuel, (I get 500+km with 15/42 sprockets), fits
straight up to the TTR mount points (using Honda brackets and Yamaha bolts), not
too wide although wide enough to have knees resting 'perfectly' for me on the
longer rides, two fuel cocks, if one side damaged close it off and run from the
other. Will take an Acerbis Locking cap for security concerns (I have found it
does not vent very well and requires a little release every hour or so for the
pressure to escape). Bad points - quite a lot of weight when full, and mates
tend to hassle you for fuel when your way out there.... :-))
Links below that I have come
across, thought this might be helpful:
http://nomadtanks.com.au/
http://www.rvaqualine.com.au/
http://www.imsproducts.com/
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What should I look out
for when buying a TTR? Generally not a lot goes wrong on one
which has been maintained well. The electronic speedo on the "white"
models is very expensive so is an
obvious item to check. Also, electric starters and sprag clutches can be expensive items to
replace so check that all sounds OK - especially listen out for the dreaded bang
when killing the motor. Otherwise, its the usual four stroke checks (see my
comprehensive buyer's checklist
) plus take it on a good run
to check handling, clutch, controls, etc. If the mud flap that protects the rear
shock has been damaged (and whose hasn't?) , check that the shock is working as they can lose damping
if the damper rod gets pitted with corrosion.
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Dating a TTR from its frame number (courtesy of Paul
Bates of Bogbusters)
Open Enduro 4GY1 4GY-000101 to 025000 is 1993/4
Raid 4GY3 4GY-025101 to 044000 is 1994
Open Enduro 4GY-049101 to 068000 is 1995
Raid 4GY-068101 to 081000 is 1995
Open Enduro 4GY-081101 to 083000 is 1996
000101 was released in the 4th month of 1993
025101 3rd month of 1994
049101 3rd month of 1995
068101 4th month 1995
081101 3rd month 1996
083101 1st month 1997
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Chain & sprocket info plus what gearing
to use for the Trail? 14-52 or 13-48 is good on & off
road compromise. Standard on "whites" was 14-44 although my new blue Euro
import came with 13-48 and a spare 14 front sprocket in the "spares"
box. Renthal part number for front sprocket is
342A-520-13 or 14 (assuming you are running a 520 O ring chain which I hope you are!)
or Talon TG415 13T (copy part - manufacturer unknown - from CMS in Exeter is
58313) or 14T. Rear Renthal sprocket part number is 131-520-52 for 52 tooth so
assume you could substitute 48 if you want the higher gearing. A 48 tooth
Renthal Ultra-Lite rear sprocket is part number
131V-520-48P-S1.
The 520R3-112
chain is a decent quality Renthal 112 link chain which fits my 14-52 sprocket
combination exactly. Renthal sprockets and chains
are available in the UK from
B&C Express 01522 791369 email
sales@bandcexpress.co.uk
B&C costs @ June 2007 were
342A-520-14 - £11.39, 131B-520-52 - £22.84, 520R3-112 - £54.80 - all inc. VAT
An alternative chain as used by ToroTrail is a Tsubaki MX Alpha MX O Ring Chain
ref 520MXA-118.
The thread on the retaining nut is RH and doesn't need to be excessively
tight as it should have a tab or lock washer. This needs to have the tab bent
back with a blunt chisel or similar before you can undo the nut. To undo the
nut, I just
put a
socket between
the sprocket and the frame to stop the sprocket turning. The bigger front sprocket is easier on the chain.
Chain noise increases when
you replace the original Yamaha sprocket with a plain one as the original has a substantial ring of rubber
built in to quieten things down. Any bigger back sprocket than 48
may need the bottom chain guide modifying although I fitted a 52 with no
problems. In the UK, Off Road Only
(01597851811 in LLandrindod Wells) stocks part 45-791 chain bottom guide
blocks which fits the TTR . US models come as standard with a bigger rear
sprocket (52?) and therefore already have the deeper guide block.
In the UK we have something called "Sod's Law" which says that the only time you
will break the tab off the lock washer is when your local bike shop is closed
for a week! It will usually allow re-use about 3 or 4 times but the washers
aren't dear so keep a couple of spares just in case - Part Number 90215-23265-00
Standard gear ratios are:
1st 2.467
2nd 1.813
3rd 1.364
4th 1.080
5th 0.889
6th 0.759
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Handlebars and levers
As a six footer, I found the original handlebars a little cramped and didn't
encourage me to get up on the pegs. I fitted Renthal Dakar high bars and
they are a lot better for me. Dave Maddock tells me that Katie also has fitted
them, as well as some bar risers (from MD Racing), which make for a very
comfortable standing position, but require a longer clutch cable. Dave sent
Katie's off to Venhill in Dorking (01306 885111) who copied it and sent back a
60mm longer version for £22 inc P&P. Venhill will make any length cable you like
as long as they've got something to copy.
Levers. David Taylor says that brake
and clutch levers are exactly the same as for the DT 125R so should be easily
obtainable. Levers are swappable between OE, Raid and blue models.
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Can I convert the digital speedo from kph to mph?
For the digital speedos, there is a gizmo offered by
Motrax
at £49.99 inc VAT.
The product code for the TT250R version is CK-TT-O1.
The blue Euro TTRs have analogue speedos driven by cable from the front wheel.
The UK "official" machines have an mph speedo!
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More speedo information:
a) What do the blue and red buttons do on the digital speedo?
The blue button switches between two trip gauges so can record two
different distances. If you hold down the blue (A/B) button for a few seconds it
switches the display from the clock function to the overall mileage function and
back again.
The red button is reset and if you hold it down for a while, about a
minute, when the clock is displayed you can set the clock when it is flashing.
The hours will flash first and you push quickly the reset button to change them,
then push A/B or blue button to go to minutes and set minutes the same. Then
just press A/B again to go back to normal display.
b) Digital speedo sender unit - this is often the cause of a "dead" speedo -
it was with mine - replacement for "white" TTRs is Yamaha part number sender
unit 4GY-83755-01 - priced at £59.78 plus VAT and P&P or £75.53 total as
at July 2004.
c) If you have terminal speedo problems
Paul
Bates suggests fitting a WR400 speedo drive unit and cable direct on to a DT125
clock, fits straight on apparently - no need to worry about gearing change and
km to miles - fits like a glove no hassle he says.
d) Clifford Eves said "After having problems with my digital speedo, and not
wanting to pay a fortune for a new pick up sensor, I decided to convert it to
cable. Just in case anyone else wants to do this I used a speedo drive, speedo
and cable from a DT125LC. It all went straight on - just had to make a bracket
for the speedo itself and all for £20.00 from eBay!"
e) For mechanical speedos, as fitted to UK blue models, Yamaha only sells
the drive mechanism in one piece (part number 4PX-25190) - price inc VAT is a
whopping £93.17 as at Feb 2008!!!
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What tyres
and tubes are best for on and off road use? MT43s do it for me! In
my opinion, the ideal for UK (muddy and stony) trail riding is probably
something knobbly (but road legal) such as a Michelin Comp IV on the front and a trials tyre such as the
4.00x18 Pirelli MT43 on the rear. A word of warning - the MT43 is quite a
"tall" tyre and is liable to chew your mudflap and swing arm if you don't give
it enough room. Other riders views on tyre choice follow:
Pat Bullen says "After a season's use I can recommend Trelleborgs Army Specials
as long lasting, very grippy and suits the TTR's steering geometry well- quite
forgiving in ruts for some reason..."
Ian Packer says - Bridgestone TW301 & TW302: Work excellently on road and
fine for off road trailing in dry or wet
hard conditions. However the tread is too close for deep glutinous mud which
will fill them and not get thrown out - they turn into slicks. Still usable on
trails provided care taken in mud. Wear rates are very good.
Michelin Enduro comp 3 & comp 4: Excellent for muddy ruts and loose sloppy
conditions. Throws the mud out well and grips well and predictably in all
conditions. Soft compound so high wear rates on hard surfaces. Feel horrible on
road particular above 60 mph. Perfect tyre for the British winter off road.
Brian Morris (Thailand) says "Fitted a set of Bridgestone ED 660 /661 at
Christmas 2004 . They are DOT approved . Both tires have very good grip in most
conditions but back tire wore very quickly and have had to replace already.
Front tire is still perfect ."
Some recent recommendations include the Michelin AC10 - a road legal MX tyre.
Apparently good in mud, and with the large blocks, will last a long time. Down
side is that you will not be able to do UK rallies on them as they are illegal
for most rally and enduro use.
Fitting Ultra Heavy Duty Michelin inner tubes
(4mm thick!) helps prevent punctures. Also, use good rim locks to prevent the
tyres spinning on the rims and ripping the valves out e.g. Talon forged 1.80
front and 2.15 rear.
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Can
I get a big-bore kit for the TTR? Plus some
tuning information....
Yep!
The European distributor for the
Thumper Racing big bore kits is
Dirtbike
Store in the UK. Whilst they do not stock the 325cc kits (which require the
cases being bored), they will supply them (£235 inc VAT)
if you order them and can have the work done if you wish.
Brian Eland imports
325cc big-bore kits and also offers the Wiseco "280" kit which is basically a new
oversize forged piston taking it to 263cc (NOT 280cc!) and involves boring of
cylinder liner only with no crankcase alterations. A mate of Lance Parsons did
it and says it results in more bhp and torque and says he can pull wheelies in
4th gear (13-52 gearing) - he also fitted a 35mm carb and got more bhp &
acceleration - had his exhaust ports bored out by Phil Manning, and again got
more bhp and quicker pick up plus he also modded the silencer as detailed below
but the dyno test showed no improvement in bhp but more noise.
See this excellent thread by
Bryan Wedmore from the ThumperTalk forum which
explains it all in more detail and with pics. Thanks Bryan - it is a very helpful resource for TTR250 owners looking for a bit more power
and better front suspension:
http://www.thumpertalk.com/forum/showthread.php?t=521772
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Can
I fit an oil cooler?
If you live near Sydney in Australia you can get a complete kit from Yamaha
Australia via your bike shop. Part number YAM-4GY-WO793-00 - cost $285
Australian at the beginning of 2002. Adam lives in Windsor NSW and got his from Wombat
Motorcycles (45878153). Speak to Gary or Angie or Jay (the new owner) and they
can order you one. Costs about $250. The kit comes with everything you need and
takes about an hour to install. The hardest part is removing the clutch cover to
replace an existing blanking bolt with a 10mm longer one to blank off the
internal oilway and divert the oil around radiator part of the cooler - see
photograph. The kit even
comes with a new clutch cover gasket. You get about 1/2 litre more oil capacity
and prolongs the life of the oil dramatically. Anybody with basic tools and
mechanical knowledge can do it. Adam says "Feel free to email me at adkaz71@hotmail.com
with any questions". For UK owners, the part is available from Yamaha
Holland via your local Yamaha Dealer - retail price is
£226.63 GBP. Some good advice is to fit a bash plate to protect the oil lines
which run from the crankcase to the radiator.
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Can I get a bigger tank for
Desert Rallys etc? Yes - Acerbis did an 22 litre plastic tank.
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How can I improve the
head light and install an on/off switch? For Open Enduro - either (a) fit the whole
headlamp assembly from a Raid which are designed for roadwork and are 50/55W
compared to the Open Enduro's 33/36.5W. I fitted a Raid headlight assembly to my
OE TTR and the difference was amazing. The lighting coil on the TTR produces a
healthy output and can run a 100W H4 halogen bulb but check it fits before
investing - these bulbs will fit the after-market Acerbis HP lamp which has a
glass lens that can handle the heat of the bulb. The standard headlight switch
and wires may be suspect running the bigger bulb and it may be worth using
heavier gauge wires from the switch to the headlamp,
or (b) install a 250LC pattern
headlight and headlight brackets from M&P for a total of £46 (£26 for the
light, £20 for the brackets).
For blue models - I got roosted big time and the original headlight glass
got smashed - very expensive to replace - a plastic KTM headlight unit is much
cheaper and fits although you will have to alter the wires a bit. Don't put a
big headlight bulb in it though coz a 90w will eventually distort the plastic
lens with the heat. If you do night trials, as I do, get a KTM Duke glass unit
(p/n 58414001100) which will take the big halogen bulbs and put a plastic one on
for "normal" riding - plastic lens unit cost £43.80 inc. bulb, p&p and VAT from Redline in Sileby,
UK in August 2003.
Quick fix for a blown original
bulb! A new headlight bulb is about £35 from a dealer. A quick fix is to
take the bulb holder out with pliers - buy a £3 car headlight bulb and bend the
tabs flat. Attach the wires and hold the bulb in place with Silicon sealer. The
light is brighter to look at and a lot cheaper than £35.
Headlight, Tail Light and Instrument Illumination Switch Installation If you don't like the "headlight always on" then fit a simple push
on and off switch (about £4.00) and splice it into the yellow and black wires
just by the left hand bar switch. A much more comprehensive solution has been
submitted by TTR250 Forum member "hp67" from Adelaide - see
http://users.tpg.com.au/cobra30/TTR250.htm
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Can I get second-hand parts for my TTR? For UK - try
Bogbusters (e-mail
pauldbates@supanet.com
) or Brian
Eland (e-mail Brian@BrianEland.com )
or via 'Partsearch' (09061119999) - and, of course, e-Bay. Please let
me know if you find another source!
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Can I modify the exhaust to improve power?
(a)
On most non-US models there is a restrictor in the header - where the header
slides inside the silencer - see
www.ttr250.com/detail+of+restrictor.jpg .
Removing this will help with mid and top end power. Just cut off the last 10mm
of the header pipe and the restrictor will come off with it.
Pictures were in Mark Williams' most excellent TTR article in
TBM a little while
ago
- Sept. 2004 edition, #109. If anybody wants a copy, they can buy a back issue
from 0208 903 3993.
(b) The standard silencer is very restrictive (assuming you have stock exhaust!) and
can be modified quite cheaply (assuming you have access to welding gear) to
improve power output. Johnny Davies from Newark, Notts, supplied the following instructions
and excellent drawings: Look at the attached diagrams (standard
and modified) before reading the next bit
so it all makes sense! Cut completely through the existing weld where
cylindrical tail section meets the 'box' section then put back on bike and fire
it up to find out which 2 pipes are the outlet. Then cut or drill through plate
holding the other 3 pipes in place then you can remove them. Grind off original
outlet pipe from tail section. Now you need 2 pipes long enough to connect from
cut section to the end of the tail section (Johnny used bits off the frame of an
old muddy fox mountain bike). Now you need to make another hole in tail pipe and
file both holes out to take then new pipes. Spot weld pipes to the 2 outlet
pipes and tack pipes together for extra strength. place tail section over new
pipes and tack in place then weld up tail to box and finish by welding around
the new outlet pipes. Then you end up with a lovely freeish flowing exhaust. (Be
warned - other TTR owners report a lot more noise but no extra bhp with this
mod!)
(c) Martin
Wilson's TTR had an XR400 exhaust on it when he bought it. The mounting
brackets all line up, it just requires a small adapter pipe between the tail
pipe and the header pipe.
(d) In a Side Track magazine article
in the series "Modifying your TTR250" it is recommended NOT to
completely remove the snorkel as that reduces power but, instead, to cut it back
one rung at the top and two rungs in the air box itself - that mod plus a
Staintune exhaust gave them a 10% - approx 2bhp - increase in power.
(e)
The October 1999 edition of the US Motocross Action magazine reported that a
free flowing end can adds power (and significantly reduces weight over the stock
item) but a larger bore header pipe did not! Shortening the existing header by
5" however produced 2bhp extra on the dyno. Not something within most owners
capabilities though!
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Carburettor setup, jets &
needles
It
is possible to re-jet the Teikei carb using Kiehin jets. What to use depends on
what year your TTR is - although a recent thread on the Yahoo forum has cast
some doubt on what the standard jets are so beware! The information I was given
some time ago was that early TTRs were 142 main jet and 48 pilot jet though from
about 96/97 the main jet was a 147 and pilot was a 50. ("50"
pilot jet is 43F-14342-25-00,
"54"
pilot jet is 43F-14342-27 and presumably the "52" pilot jet
is 43F-14342-26-00 - about £10 each in UK).
At least one owner has a 96 Open Enduro with 137 main and 50 pilot jets - very
confusing! However, something definite I hope is that the blue TTRs are shown as
having 137 main and 50 pilot on the online microfiche at
http://partsfinder.onlinemicrofiche.com/xtremepowersports/Yamaha_OEM/YamahaDB.asp
Johnny
Davies TTR (see
above) was a later
model so he found a local carb specialist that did Kiehin carbs, took in his
main jet and needle jet and they tried a standard round Kiehin main jet and it
fitted perfectly. They measured his original jet and it was 1.47mm (apparently
different makes of jets don't always mean that the no. on the jet is the size in
mm) and suggested trying a 148mm, 150mm, and 152mm (Kiehin). Johnny tried them
all (about £3.00 each) 148 no difference, 150 spot on, 152 too rich (like
running with the choke on). Johnny has left the snorkel off the air box and has
the needle on the standard position. He is looking at different needles at the
moment, also he has left the mixture screw at 3.5 turns out compared to standard
2.25. The firm he used is:
Allens Performance
Ltd, Unit B9, Moorbridge Road, Bingham, Notts,
NG13 8GG - tel. no. 01949 836733, fax. 01949 836734
You should get better power throughout the range.
Yamaha part numbers for jets as
follows (thanks to Mike Stoddard):
288-14329-71 #142
4GY-14329-73 #145
4GY-14329-74 #147
Rage Performance and
Bike Bandit in the US can supply Keihin and Mikuni carb jets. See also
Sudco
Karl
Goellner says "The small Mikuni hex sized ones don't come in half sizes but just
full sizes however the large round ones ( N100.604 )do come in half sizes like
(142.5). I used this type and know for sure that they will fit although it's a
pretty tight fit. With the stock exhaust and only the silencer removed (still
has the spark arrestor screen), the large
type Mikuni #140 jet with the needle in the stock position works great at 600
ft. elevation. It adds a little more punch for about $5.00. Also, I've done
nothing to the air box, it's completely stock and unaltered."
More
information on personalising your TTR and "uncorking" some power - see
this
posting on Thumpertalk at
http://tinyurl.com/mvntl which has some useful pics and links courtesy of
Aaron Cooper.
Problems with carburation after long-term storage & non-use. Geoff Denham"
says: I have a 2001 TTR250 (North American version). I had cold starting
and idle problems. I found out that the previous owner had stored the bike for 2
years without draining the fuel from the carb. I then discovered why he hadn't
drained the carb - the Philips head of the drain screw was stripped such that no
screw driver could turn it. The jets in the carb. were blocked up with residue
from the evaporated fuel, and the throttle pump diaphragm had become hard (long
term storage). I removed the carb. from the engine and had it overhauled by the
Yamaha dealer. In most cases it maybe just gummed up jets. Check to see if you
can drain the carb. If your drain screw's head is stripped, have the carb.
overhauled. Removing the carb can be quite a big job if the air box is removed
first. If you do this, take careful note of the connections and routing of the
various rubber hoses connected to the carb. Its a good idea to thoroughly clean
the inside of the hoses and their one way valves etc. You should download the
Yamaha service manual, I found it very helpful. I should have added, after I had
removed the carb, I also removed the rubber intake manifold and refitted it
with an application of a high temperature sealing compound. All this effort was
rewarded with new bike starting, idle, and general good manners. As in this case
of my low mileage bike, such results assume there are no other significant
engine problems. if you're having problems starting, it might be time to check
your valve clearances. 25 April 2007
Click here for further information from James_AZ_USA.
Carb drain screw. The Philips-style head on these strip out easily so use
the best-fitting screwdriver you have. Make sure that you have the carb body
held firm so that you can put pressure on the screwdriver to prevent it jumping
out of the slots. If it goes wrong, the part number for a new one is
14T-14104-00-00.
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What brake pads fit? (Info from Paul Bates - thanks mate!)
TTR250 brakes same as WR200, rear same as Serow, front same as TS200
and RMX250. Part numbers by manufacturer as follows with rear given first: Apico
BP100 and BP002, Vesrah VD432/2 and VD340, EBC FA152TT and FA135, SBS SBS648 and
SBS SBS611, Ferodo FDB659 and FDB497, Dunlop DP315 and DP411.Good parts shops
should have sets in stock but any dealer with a "Hi level" account can
get them next day if not in stock. EBC Sintered Pads - Front FA135R and
RearFA152/2R, they are listed in the ORO catalogue as the same as the ORO gold
pad 211CC/SM and 315CC/SM.
I personally use the sintered Ferodo pads as they seem to work well on and off
road and last a sensible amount of time. Brian Eland likes the Kevlar EBC pads
which apparently give loads of feel to the lever but are "softer" and
he reckons they need changing probably after one rally and two trail rides as
the pads are wrecked by then (could be Brian's wicked riding though!).
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Fitting rear pads. Advice courtesy Brian Eland.
Take the brake guard off - loosen the rear wheel spindle bolt - loosen the front
bolt on the caliper body - tilt it forward - open out the brake caliper to push
the piston back - take out the brake pin bolts - you should then be able
to drop the brake pads down then remove them backwards. On installation to put
the pins in you have to push the pads slightly up against the anti chatter springs,
Copper Slip the brake pins very well and tighten very carefully - if you
over tighten the pins will stick and have to be drilled out - any doubt
about the fit of an Allen key into the brake pin do not put the pin back in -
replace it instead.
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Oil changing. The
filter is a common off-the-shelf Yamaha part
- I used a Champion X313 last time around (Yamaha Part No is - 1UY-13440-02-00). Dave
Maddock found that the oil filter is the same as the YZ\WR 400\426 (not the 450)
and the pre-03 YZ250F, which makes pattern ones widely available. He got his
from Racespec in the UK (part number 78-142 - £5.20) who also supplied a CRD air
filter (part number 23-1015 - £7.50).
1.1
litres of oil needed unless you have a oil cooler on then it maybe a little
more.
Lance Parsons was advised to use a semi-synthetic oil and uses Castrol GPS
"Extreme Protection at High Temperature Semi-Synthetic 4 Stroke Motor Cycle
Oil" which claims to be "an advanced semi-synthetic 4 stroke engine
oil formulated to maintain a tough renewing layer of protection for bikes ridden
hard. Castrol GPS provides excellent wet clutch performance and consumption
control". Lance changes his oil every 1,000km but that's down to you to
decide. If you have just driven a hard 3.5hr Hare & Hounds then I would
probably advise changing it!
Haynes Manual Recommended lubricants for Engine/Transmission are: Type: API grade SE or SF multigrade oil,
Viscosity: 40-degrees F(5-degrees C) or above:20W40 or 10-degrees F(-10-degrees
C) or below:10W30
If you start to use oil, and the engine is smoking, its always worth fitting new
valve guide seals - part number 33M-12119-00=00 - before going for the expensive
rebuild.
Tyler Watts says: All these engines ask for is good oil and for it to be changed
regularly. You can even use average off the shelf stuff from the service station
(I'm not recommending it though) as long as you change it regularly. Regularly
depends on your riding. Off-roading, hill climbing, overlanding etc would
require more regular changes approx. 500-1,000 miles. Less strenuous riding like
commuting could extend this.
A good tip for knowing when to change the oil is if you're riding along sedately
and just short-shifting through the gear box, you will notice the changes get
more 'clunky' or stiff. It is simply the gearbox saying it's used all the good
lubricating the oil can offer and would like some new oil... My engine had never
been opened after 20,000miles, and was great. All that went wrong was a cylinder
base gasket leaking, and then a nit on the end of the spanner putting the timing
wrong and turning over the engine, ramming the piston into the intake valves...
Otherwise, she is amazing and the mileage is loads higher now!
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Can I get a bash plate and frame guards for my TTR? CRD no longer
make these items but fortunately the Australian firm
B&B Offroad
Engineering do!
Brian Eland
imports these items to the UK
at a cost of £84.95 and £38 respectively (plus p&p)
Advice from Adrian -
March 2006 - "Another bash guard option is one from these peeps
p1autotech
They get the American
Baja Designs one and are only £63 inc VAT, p&p. If you're lucky they may
have one in stock, if not though they have to come from the USA so take
sometime. My mate bought one and for the money its not too bad at all, they are
strong but the fitting kit is a little fiddly and not as simple or probably as
rigid as the CRD one, but then it is £20 cheaper. I recommend
you phone the guy to make sure he has one though on 0845 838 0706 or e-mail
sales@p1autotech.com I hope this helps, Oh and I have no connection to this
company just trying to help."
.
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Need a grab handle for your
blue TTR?
Dave Maddock has recently bought the "missing" grab handle (the left hand side
one he thinks) - part number was 4PXF-12750-000. Pricey at £35 but hopefully
worth it in the long run. Apparently the handle is part of the UK road-kit
(along with a few other bits) and it isn't listed on the fiche. The dealers have
a separate booklet for these parts. The UK spec bikes should already have it but
most of the parallels and semi-official ones don't.
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Batteries.
A new battery (GS Valve Regulated
Lead-acid battery GT7B-4) cost me £33.47 (in VAT) in Jan 2004 - off the shelf
and charged - from CMS (telno 01392 467700) in UK - part number 4UC-82100-01-00. A cheaper alternative suggested by Perttu
of Bangkok is to use a computer UPS Battery (flat connectors). He is using
one in his TTR and it works fine in upright position. Its a Panasonic LC-R127
(7AH) and it costs only 450 baht ($10US) in Bangkok. Looking at the battery you will have to extend the leads a bit but it sounds
worth it for the price. Thanks Perttu!
Dave Maddock says: "TTR batteries are
not the easiest things to find and my usual supplier (local battery factors)
couldn't help. Yuasa UK assured me that there is a Yuasa equivalent (YT7B-4) so
a Yuasa dealer like M&P should be able to get one, but it'd probably cost the
same as OE. I managed to get one for £35 inc VAT from a place in Telford called
Moto Sifam UK (01952 580500 -
info@motosifam.co.uk). They advertise in the MCN battery classifieds as
Chase Batteries, but in reality they're a motorcycle parts wholesaler, who are
happy to supply individuals. They had a Kyoto YT7B-4 in stock (they're the
importers for Kyoto batteries) and they can do next day delivery if required. A
useful alternative source to Yamaha."
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Kick
start kits - part number
4GY-W0795-01-00
In the UK, these are available from
Brian Eland - approx. £310 - not cheap! - see www.BrianEland.com
In the US, these are available from
suppliers such as Mr Motorcycle - approx. $286 - see
http://www.mrcycles.com/eshopprod_cat_1609-3795-9101_product_148028.KICK_START_KIT.htm
Kick start kit installation – by
Nik Codling 28/05/02
Having installed the Yamaha kick start kit for the TTR250 myself, I thought
I’d share my experiences with others, and hopefully make the job slightly
easier for anyone attempting it. First thing to note is that it can’t be that
hard – I managed it ok, and it’s pretty straightforward!
The instructions that come with the kit are probably really good. I say
probably, as it is more suited to those who have a good grip of Japanese, being
as it is written entirely in said language! The Japanese language is visually
very pretty, although my grasp of it is roughly equivalent to my grasp of female
logic (very small!), although I did once try Sushi.
The instructions do have a few diagrams, which certainly give you the basic
information to be able to complete the job, although there were a few occasions
where I had to make a couple of guesses!
First job is to remove the right hand engine cover. You will probably find this
is made easier by removing the brake pedal (just undo the pivot bolt) and the
foot peg (two hex/Allen head bolts). The engine casing itself is retained by a
number of hex (Allen) head bolts. You will also have to remove the oil banjo
bolt above the oil filter.
A good idea when you remove these is to place them down on a clean surface, and
lay them out in the order they came out – the bolts vary in length and it’s
easy to mix them up otherwise. Of the three oil filter bolts you only need to
remove the outermost one, although it’s a good opportunity to give the oil
filter a clean while you’re at it.
Once all the engine cover bolts are out you can take the cover off, exposing the
clutch assembly. It’s at this point that you discover whether you remembered
to drain the oil or not! In my case I hadn’t, and some lovely new semi
synthetic deposited itself on my garage floor!
In order to install the kick start assembly you need to remove the clutch
assembly. This may seem scary to the amateur mechanic, but it’s pretty easy.
The clutch plates are held in by six bolts, with a 10mm head. Slacken these all
off a little bit at a time – try and undo them all evenly, and not one at a
time, it puts less stress on the clutch basket that way.
Once the bolts are undo you can withdraw that clutch plates in one go, complete
with the clutch cover plate (not sure the correct term!) and the six bolts and
springs. The clutch basket is retained by a large nut with a tab washer, and
you’ll need a 27mm socket to undo it. Tap the tab washer out of the way,
allowing access to the nut.
At this point you’ll need to prevent the engine from turning over, in order
that you can undo the nut. A professional mechanic would have a device to hold
the clutch basket, and prevent it from turning. A less scrupulous mechanic would
insert the largest spanner they have through the back wheel, but I wouldn’t
recommend this practice!!! Once the engine is held the nut is pretty easy to
undo, and the basket can be withdrawn from the splined shaft.
Behind this is a large flywheel (again, not sure of proper name!), and this is
retained by a castellated washer – remove this, and off comes the flywheel.
To the left of the flywheel is a small shaft, with a blanking piece on it,
retained by a circlip. Remove the circlip and blanking piece. The shaft is then
fitted with a circlip and washer, and one of the large gears supplied with the
kit. This is held in place with a washer and circlip. Make sure you fit the gear
the right way round (it should be obvious, depending on whether you can rotate
it once fitted). Once this is in place you can re-fit the whole clutch assembly.
You might want to take this opportunity to inspect the clutch plates, and make
sure they’re within spec (use vernier calipers to measure the thickness of the
friction material). When re-fitting the clutch bolts be careful not to
over-tighten (refer to workshop manual for correct torque).
Next job is to fit the kick start “stop”. This consists of three small metal
plates, which prevent the kick start shaft from being turned beyond a certain
angle. You will find two threaded holes to the left of the clutch assembly that
these are fitted to. Fit first the smallest “plain” plate, then the really
thick one (ensuring that the big tab is pointing upwards), and finally the plate
with the two tabs on it (with the tabs facing towards the left). Screw in the
bolts to approx 10nM (i.e. not very tight – you really don’t want to strip
the threads, but tight enough that they won’t undo) and bend up the tabs to
help prevent the bolts undoing.
Next up, you need to fit the splined shaft that the kick start return spring
hooks over. This goes into a hole towards the bottom, below where the kick start
“stop” is. The hole isn’t splined, and you may feel as though it isn’t
the right place. It is, it’s just that it needs a damn good whack to get it in
there! I started off using a nylon-faced mallet, but ended up using a lump
hammer in order to hit it hard enough to get it in the hole! Mind you don’t
over-do it though, after all, most of the engine consists of softer
aluminium/alloy parts. Try and hit the shaft square on the end, so that it
doesn’t go in at a funny angle. Be careful not to put the shaft in all the way
– leave about 2-3mm of the splines sticking out.
Now you need to assemble the kick start shaft itself. This is quite easy, and is
illustrated in the instructions (refer to Shawn Crowell’s .jpg in the Yahoo
Groups files area). First fit the big gear, and retain it with a washer and
circlip. Then fit the “ratchet” – note the orientation as per the above
jpeg. Next is the smaller spring, large spring-retaining washer, and a circlip
to hold it all in place. A washer is then slipped over the top of the circlip,
prior to installing the shaft.
At the other end of the shaft is the big kick start return spring. This is
pretty straightforward, just hooking it in to the slot in the shaft flange.
Within the spring sits the large, thick washer. This just sits in place and will
be retained by the engine casing, once it's in place.
You can now insert the kick start shaft into the engine (make sure the washer is
on the end of the shaft). It literally just sits in a circular recess. Once in
place hook the kick start return spring over the splined shaft that you fitted
earlier. It’s worth checking that the splined shaft is fitted to the correct
depth, by checking how “square” the kick start return spring is sitting.
At this stage you may wish to make some adjustment to how much tension the kick
start return spring has. As stated in the instructions, I felt it was a little
weak - note the illustration showing the correct assembly of the ratchet piece,
in conjunction with the kick start shaft flange. I therefore rotated the shaft
assembly round by one spline, to give a little more pre-load to the spring. This
is slightly tricky to explain, but becomes obvious once you trial fit the kick
start shaft in place and try turning it by temporarily fitting the kick start
lever.
Once this is done you’re ready to go about re-fitting the engine cover. First
of all though, you need to remove the bung from the engine cover, in order for
the kick start shaft to come through. I inserted an appropriately sized socket
into the hole behind the bung, and gave it a whack, and out it popped.
You can now re-fit the engine cover, oil banjo bolt, brake lever and footpeg,
and all that’s left is to fit the kick start lever, and off you go! The whole
job shouldn’t take more than a couple of hours – I was being careful and it
took about three hours, but someone more proficient/confident would be much
quicker than that (and probably wouldn’t need this anyway!).
I’ve written this from memory, and I may well have missed stuff out, but I
think that’s it!
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Starter Motors
Starter motors and the associated
sprag (one-way) clutch seem to be a weak point on TTRs if excessive noise when
cranking or banging when switching on/off is ignored - replace the sprag clutch
to save a much more expensive rebuild - see Tim Wood's article in the next
section. If you have left it too long and major repairs are needed then I
hope Lance Parson's advice below helps:
A common problem if left too long is that the large idler gear shaft boss ends
up having a section of casting broken off. As at June 2007, the UK price new is
about £173 inc VAT (part number 4GY-15411-02-00). Lance has been told of an owner
who had the same problem and had the boss rebuilt by welding etc, but it broke
again shortly after.
Following his own starter problems, Lance needed to replace the outer LH crankcase cover, two idler gears and
shaft plus the starter motor on his TTR. The new price for all of these
parts was £600.00 from Japan
via
BAT Motorcycles - 01959577145 (delivery to UK in six weeks),
or £450.00 from
Holland (delivery in two weeks) - (new starter is £214.81 on its own) - via Ray Hockey
Motorcycles (01873840170). Also, in the UK, serviceable 2nd hand parts can be
obtained via Paul Bates and Brian Eland (details below) or via
'Partsearch' (09061119999) - they located one for Lance from Black
Knight Spares (Trade Breakers) in Doncaster 01302840409, £123.00 the lot
delivered to his door next day. For his £123.00 he got the bits to repair the starter mechanism
i.e. LH engine cover, two idler gears and shaft, plus the starter motor, I doubt
others will get a bargain like that again!
A friend of mine, Adrian Harris, rebuilt a TTR starter, to replace the mangled
pinion gear, using an armature centre and good pinion from a more common Matsui
starter. Check out
www.dirtybiking.co.uk
.
Peter from France says he has found an easier solution than modifying an FZ600
starter! He says it is possible to use one from a Honda 125 NX (or Transcity)
and all you have to do is change the rear cover - everything else is the same.
Thanks Peter!
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Replacing
the one-way starter bearing or sprag clutch (courtesy of Tim Woods)
The repair was fairly easy, but I have been working on bikes as a hobby most
of my life, I'm 45 now. The parts were under $70 (the one-way bearing costs £89
in UK), and you will need a flywheel
puller (Yamaha part number is 2K7 85555 00 about £4 in UK). The shop that I went to didn't have a puller in stock and they
couldn’t find one in the after market catalogue. What I found that worked
great is a spark plug thread cleaner made by KD tools part #730 it has a 18mm x
1.5mm on one end (that's the size needed for the flywheel) and a 14mm x 1.5mm on
the other end, it's made from hardened metal. You will need an air impact to
pull the flywheel; there is no way to hold the flywheel from turning if you use
a socket wrench. (Andy Yates says "Soak components in WD40 or your
favourite penetrating lubricant, stick the bike in gear, wedge a large lump of
wood through the back wheel so it jams against the swing arm and cant rotate.
Get someone to stand on the back brake. then stick a BFO length of scaffolding
tube on your 1/2" breaker bar and apply force." At your own risk
though folks!)
Here are the steps.
1 Drain the motor oil.
2 Lay the bike on its right side.
3 Remove the counter sprocket cover.
4 Remove the small cover, the one with three bolts, where the starter gears are.
5 Remove the starter gear under the cover (the starter doesn’t need to be
removed).
6 Remove the mag. side cover and lay it over to one side; the wires don't need
to be unplugged.
7 Remove the bolt in the end of the crankshaft.
8 Thread the flywheel puller in the flywheel.
9 Use an air impact to remove the flywheel.
10 Remove the six Allen head bolts from the front of the flywheel, they are put
in with lock thread so they are tough to remove and the bolts will be junk after
they are taken out.
11 The one-way bearing is now free to come off.
12 When you replace the new bearing use lock thread on the new Allen bolts, I
used Red Locktite 721.
13 After the bearing is installed put the flywheel assy. back on the crankshaft,
I used the air impact to install the bolt, but be careful and don't over do it.
14 Install the mag. side cover, with a new gasket.
15 Install the sprocket cover.
16 Fill the crankcase with 1100cc of oil.
17 Start it up and check for leaks.
This was the first time I made this repair and it took me about two hours. Hope
the info helps everyone, sure beats $60 per hour that the shop charges, and I
like to know how everything inside the motor works anyway. (See also
www.dirtybiking.co.uk
)
Here's a list of parts you will need:
1 x One-way bearing part # 4GY-15590-00-00
6 x Allen bolts part # 90110-06091-00
1 x Side cover gasket part # 4GY-15451-00-00
1 x Flywheel puller KD # 730 from the auto parts store (or Yamaha puller has
part number is 2K7 85555 00).
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Clutch plate information. Information courtesy of
Lance Parsons:
"Plate Friction: 3XJ-16321-00-00
Spring Compression: 90501-23391-00
and, in case you require the plain plates, Plate Clutch: 3XJ-16324 -00-00.
Although Ronnie's OEM parts list starts at 1999 for the TTR, I have used it for
my '93 4GY with no problems. My experience is that TTR part numbers NOT starting
with
'4GY' are common to other Yamahas."
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Fork Seals
and refilling forks
Raid 94 fork seal details - guess most white TTRs would use the same -
43x55x9.5/10 ORO part no 57-701 £7.95 - fork seals with wipers ORO part
no 57-804 £31.30
Oil type and capacity - Lance's
Haynes manual says: Capacity: 555cc, Type: Yamaha fork oil "01" or
equivalent, Oil Level: 130mm (fork fully compressed and spring removed)
Head stem bearing inspection or replacement.
This job must be done by 2 people.
Set bike up on stand with front wheel about 100mm off the ground. Pull off
headlight cowling, undo the 3 bolts and pull forward headlight/speedo assembly,
then unscrew speedo cable and unclip wiring, then remove the headlight/speedo
assembly. (spraying a little CRC, RP7 or the like into the wiring clips doesn't
hurt). Place a rag over the front mudguard as the handlebars and other bits will
soon rest there. Keeping everything intact on the handle bars, just remove the 4
bolts and pull the bars forward and lay them on the front mudguard, all the
wiring is long enough to accommodate this.
Next undo the 4 bolts holding the front indicators to the forks, lay these
indicators also on the front guard, (once again the wiring is long enough.)
Remove the main nut securing the top fork/head stem bracket, then using a large
screw driver, pry open the fork clamps on the top fork/head stem bracket. This
bracket can now be removed.
Place a block of wood under the front wheel so it is JUST supporting the weight.
With one person standing in front of the wheel making sure it doesn't roll
forward (it will want to very soon) remove clip/lock nut, main nut. The whole
front fork assembly will want to roll forward at this point. Supporting the
weight of the wheel, remove the front chock of wood and gently lower the wheel
to the floor. As the whole thing wants to roll forward be careful not to damage
the thread, the top bearing will pop out when the wheel is lowered.
The bottom bearing is now completely exposed so now both can be greased. One
person can service the bearings while the other stops the wheel coming forward.
Replacement bearings are part number 93332-00078-00 but in the UK are about £40 if you
order the genuine Yamaha parts. Koyo ones (ref 320/28JRRS) are apparently exactly the same
bearing and are available from
Moto-Ward at £41.51 the
pair or B&C Express at
£31.62 both inc. 1st Class posting as at June 2007.
When finished, lift the front wheel up (careful of the thread), place the wooden
chock back under the wheel and install the top bearing and nuts (THIS IS A TWO
PERSON JOB) then fit things back in reverse order of the way they came off. Fork
pinch bolts - torque setting is 23Nm – the same as the handlebar clamp bolts.
There you go, it sounds complicated but it is really quite simple and quick.
Many thanks to Matt Selleck for this!
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Spark Plugs
Off Road Only (ORO) do the Splitfire range of plugs for the bike, if you use
either the CR8E (standard) or the CR9E then the equivalent Splitfire is either the 430B or
C.
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How can I lower the
TTR250?
It is possible to drop the front forks through the clamps to lose some height
plus some owners have modified suspension link arms. The final solution quite
often is to sculpt the seat foam (apparently an electric carving knife does a
neat job!) but it is worth checking out the availability of an early TTR seat
as these appear to have
thinner seats than latter ones and a s/h replacement might save time
over cutting, shutting and recovering. Its also worth knowing that Kouba make a
lowering link - see
www.koubalink.com/TTR250.html
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Where can I get a manual?
a) An online manual that I have downloaded and is of excellent quality is
at
http://www.omlb.com/xteam/ttr250.pdf
It's about 25Mb worth so be patient!
b) In the UK, the guy to contact for a pucca Yamaha paper manual is Gordon Brush,
Customer Relations Dept, Yamaha UK, Sopwith Drive, Brooklands, Weybridge,
Surrey, KT13 OUZ (Tel 01932 358000). A bound photocopy of an English manual
costs £20 - make cheque payable to Yamaha Motor UK and supply your frame
number. If your TTR250 is Japanese import like mine (frame number starts 4GY)
then a lot of the electrics etc may be different but motor details should be
pretty good.
c) There is now a Haynes manual on: Yamaha Trail Bikes 1981-00 Haynes 2350,
PW50/80, RT100/180, TT-R90, TT-R225, TT-R250, XT225, XT350.
Available to Rides List members at a discount from Mike Husband at Merlin books
- http://www.merlinbooks.com
. Covers only the American spec TTR250 "play bike" though but a UK TTR
owner who bought it says its still very useful.
d) English Owner's Manual for blue TTR250 is part number 4PX-28199-25
e) Recent (Feb 2004) information from Dave Maddock: "Apparently Yam UK are
getting French models and modifying them in the UK to meet the regs, rather than
getting a full UK-legal import direct from Japan. They suggested Oz or the US
for an English manual. I managed to order a genuine Yamaha one from RepairManuals.com in the States. All up cost was about $65 including P&P, which
with the weak dollar works out at a very reasonable £35. They also do the parts
microfiche for $15 but I didn't bother."
f) As a last resort, you can e-mail me for a CD ROM copy of the full workshop
manual for a TTR 250 for £5 (unfortunately the scanned images are very poor but
users have said its still very useful!). Stephen Hogan <wheelieboy@optusnet.com.au>
is the Australian contact for the CD ROM - thanks Steve!
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Wheel Bearings
and seals.
The wheel bearing on the TTR250
are sealed. Replacing bearings can be a challenge until you get to know how they
fit. The collars are press fit into the inner race of the bearings and you need
a large drift or a press to get them out - be patient and careful!
Rear wheel takes
3 x 60/22 2RS size - 22x44x12 and oil seals for wheel 2 x 28x47x7.
Front wheel LEFT takes 1x 6003 2RS - size 17x35x10 and oil seal is
22x35x7.
Front wheel RIGHT takes 1x6202 2RS - size 15x35x11 and oil
seal 20x35x5.
In UK, best bearing
costs I found are at
B&C Express @ June 2007.
60/22 2RS - £9.55, 6003 2RS - £3.30 and 6202 2RS - £3.30 inc VAT
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Clutch inhibitor switch replacement
Off Road Only in the UK can supply a replacement
handlebar clutch inhibitor switch (part 44-022) with one that is not a direct replacement i.e. clip fitting different in clutch lever
perch and the bullet connectors need cutting and soldering to the existing
spade connectors - thanks to Nick Searle for this. However, Dave Maddock tells
me that the genuine Yamaha part (4GY-82917-01-0) including lead only cost a
tenner (UK money!) .
Hasse Prefect says: As far as I know there is a sidestand switch, a neutral
switch and a clutch lever switch. Both the sidestand switch and the clutch lever
switch you should bypass, the sidestand may bounce as you go over woops and then
the engine will cut out, also the cables may rip when going through bushes and
stuff. The clutch lever switch (according to Sod's law) will break down when you
are very far from home and the sun is setting..... It is nice to have the
neutral light but it is by no no means necessary, bodging the clutch lever and
sidestand switches should be enough -following the rule that "if it is not there
it can't break". 26 April 2007
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Adjusting the sag.
Rear preload is set by having the
suspension full extended. At full extension, measure from the centre of the axle
to a point on the sub frame and note the distance. Next, with riding gear on,
load the suspension with your weight positioned on the bike in your normal
riding position. You might have to have someone assist you by keeping the bike
upright! Measure from the centre of the axle to the same point on the sub frame.
You should have about 100 mm less distance with the suspension loaded. Adjust
the preload on the spring until you get the 100 mm differential.
After getting the 100 mm sag, next check your static sag. This is how
much the bike settles from full extension with just the weight of the bike. You
should have approximately 35 mm free sag. If your free sag is considerably more
or less than 35 mm, you probably will need to exchange the spring. Thanks to
Jack Hixson for this piece.
Thumpertalk's
"Set your sag" link.
Repairing the rear shock. From Matt Lauck: "Mine was blown and I opted to
have it rebuilt rather than spend the ~$500 for a new one from the dealer. I
removed the shock (very easy) and sent it to Aftershocks in California. They did
a good job rebuilding it and getting it back to me. Total cost was $180
including shipping. Cheaper than the alternative and something to keep in mind
for others out there.
http://www.aftershocks-suspension.com/
Rear suspension linkages. It is recommended that
you check the rear suspension links occasionally to check all the seals are OK.
If water gets in then you will have problems. The needle rollers are the poly
lube type so don't need greasing as such.
A good tip is to WD40 the damper rod on the rear shock after
power washing - if it gets pitted you lose the damping and its expensive to repair
- if this advice is too late, for owners in the UK, Revs Racing of
Halesowen (01215013321) can repair and re-pressurise the shock - costs about
£90 - thanks for that tip Lance!
Having just replaced my swing arm bearings (Nov 2003), I hope the following
information will be useful to others.
Stripping out the swing arm out of the bike was straightforward enough but you
will need a couple of deep sockets. I was lucky that the “connecting rod”
bearings and seals were OK as were the shock absorber “rose joints” but, because
of water ingression, I had to replace most everything else. Also, I only
replaced one swing arm cover and oil seal as one of the metal covers had been
damaged and had let in water. The other side was fine however the cost quoted
below in the total assumes both were replaced. I couldn’t see how to get the
swing arm needle roller bearings out with the tools I had so I paid an extra £10
for the bearing shop to do that. They were able to match the original NTN
bearings but I have not checked their prices against getting the same bearings
through Mr Yamaha and have assumed, hopefully, they were cheaper!
Swing arm bearing renewal:
Bush (29L-22184-00-00) - £21.77
Bearings (NTN TA2025Z) - £10.69 x 2 = £21.38
Covers (30X-2219X-00-00) - £2.47 x 2 = £4.94
Oil Seals (93108-35004-00) - £2.47 x 2 = £4.94
Relay Arm bearings:
Bearings (NTN HK2220) - £5.58 x 2 = £11.16
Seals (20x27x5-R23) - £2.94 x 4 = £11.76
TOTAL INCLUDING VAT: £75.95 plus any fitting charges
I have just found that, in the UK, Off Road Only do
an
"All Balls" linkage bearing kit ref
17-2840 which
seems good value at £48.27 inc VAT (as at March 2008).
More
detailed information courtesy of Kevin Baker.
Rear shock absorber bearings.
Following Cal's warning that the rear shock bearing and seals were around $90
AUD (£38.50 GBP) from Yamaha I decided to strip and re-grease mine whilst I had
the swing arm off doing those bearings. All Balls supply the
bottom shock kit if you need to replace it - about £12 inc VAT. If you have
a good source of cheap bearings then the part number is GE14ES/K and the seals
are "Clark Seals V5 18.5 x 26 x 2.7".
The collars on the bottom bearing came out easily by levering them off
with a wide blade screwdriver.
HOWEVER, it was not the same story with the top bearing collars - Yamaha part no
90387-100Y3-00 (cost £11.16 for both). These collars have very wide "flanges"
and my first attempt at levering them off with the screwdriver broke a large section off the flange -
after a struggle I managed to get both flanges off but destroyed them in the
process! I have since successfully removed them in
one piece by giving them a good soak of WD40 and then using a punch on the
inside lip. Once one is out, the other is easily removed. The wire circlips are
tricky unless you have a very fine screwdriver such as used for spectacle
screws. It is possible to lever out the circlip just enough to get pliers on it
or a bigger screwdriver behind it to get it out all the way.
It isn't possible to source the top "spherical plain" shock bearing as it was a
"special" - inside diameter (id) 12mm, outside diameter (od) 26mm, inner ring
width (ir) 15cm, outer ring width (or) 13mm.. However, if you are prepared to
compromise, it is possible to source alternatives. I used a GE12FO whose only
difference is that the "or" is 9mm so it needed packing out. The alternative
standard bearing has a slightly wider "ir" at 16cm and I do wonder whether I
should have used this one and perhaps found a way to take 0.5mm off each side.
The Yamaha part number for their seals is 38V-22211-00-00.
For most bearings in the UK try
http://www.simplybearings.co.uk/shop/index.php
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Installing
a Scott's Steering Damper on a '99. This article is courtesy of Paul
Garlick - thanks Paul!.
I had the reaction post welded to the frame by a professional, but since I
installed my unit I have seen a lot of Scott's dampers installed with the
reaction post bolted or clamped to the frame. This makes it a DIY. job and the
riders said they hadn't had problems with the post working loose. Personally I
like the added integrity of the weld.
I installed Renthal Jimmy Button bend h/bars so that the
damper would fit under the cross-bar. I left the settings stock for the first
several rides (Scott recommends this), eventually I increased the low speed
damping resistance one or two clicks. I haven't adjusted the arc (steering
angle) limits, the damper has adjustable arc limits to minimize arm pump.
If you put the bike up on a stand you can feel the
resistance when you swing the handlebars through their travel. It's not much.
One of the sales features of the Scott's unit is that it has low speed and high
speed damping circuits. It's the low speed side you can feel. The more low speed
damping you wind in then the less effective the high speed circuit becomes.
It's great, I ride in the woods with the roots and
rocks and it really helps. I just makes you feel that you are having a good day.
It's the high speed circuit that is working when you whack a tree really hard
and the bike keeps more or less on track - instead of doing a tank slapper into
the weeds.
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Clogging of front
sprocket on white TTRs. It gets pretty tiresome removing the cover
every time the bike gets near any dirt just to clean it out. Johnny Davies has modified
the cover to allow mud etc to escape rather than build up into a nice compacted
lump around the front sprocket - pictures in the Files area of the TTR250 Yahoo Group
- in the "sprocket cover pics" folder. Looks simple but effective. The Y2K TTRs have a conventional speedo
driven by a front wheel cable so don't suffer quite so much with this problem.
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Smartening up your TTR
Replacement decals
At long last it is possible to buy reasonably priced good quality replacement
decals for your
Open Enduro
or plastic-tanked blue TTR. Karl Barker of
D&D Graphics has liaised with
his partner Thrushara in Sri Lanka to produce some cracking designs. I must
confess to being biased toward the standard design (the
"Standard.com" version) decals. Maybe it's because they include
the TTR250.com web address? I have had these on my 2004 TTR for a while now and
they fit well and are still looking very good. They are amply perforated so
minimal
bubbling and any that do appear can be easily squeezed out.
NEW! Karl has just sent
me a pic of new decals for the TTR based on the 2007 WRF graphics - looks good
to me so I may have to put my hand in my pocket for a set to tart up my TTR for
the trail riding season ahead. See
http://www.ttr250.com/2007graphics.jpg The TTR 2007 WRF style tank set are
£40 and include some other generic graphics in the pack. There is also a full
bike kit for £80. Both prices include recorded Shipping.
Karen Bunker has also found a source of TTR decals at
http://xgxracing.com/ She says they have lots of perforations… had them on
all summer without draining gas with no bubbling! Karen also found another
supplier at
www.enjoymfg.com . Thanks Karen!
Also
Enjoy Mfg supply Yamaha Element 1 Graphics for the blue TTRs.
Clint Smith says "The graphics are made in the USA and are very good quality"
Replacement for tail
light and number plate holder (applies to UK)
Some owners have replaced the bulkier original item with a small Acerbis unit
and connected the original number plate wires in to give a small LED tail light
slightly under the rear fender. Brian Percival said he had to trim a little off
the end of the unit (2 cm or so, one cut with a hacksaw) to fit under the
existing tail light/frame loop and fabricate a small plate to hold it in place
using the existing frame mounts and one bolt. Once cut it actually wedges neatly
between the loop and fender. It's also a plus because you don't have to drill
the fender. Very easy to do and took about an hour. Try
www.bertharkinsracing.co.uk (01582 491076) - Acerbis no: 0008326.090
Replace those big
indicators! Just fitted a set of Motrax Micro Fairing indicators to Tim's
OE. Click here to
see pic.
Frame paint
The "white" TTRs frame is Yamaha Deep Violet Blue - to touch it up get
a can of PJ1 "Yamaha Purple 1994 Epoxy Paint" - I have to say it is
bloody good paint and matched my old TTR frame's existing paint exactly. PJ1
Part No 17-YP4. PJH list the frame paint for "98-03" models as
17-YB8. Click
for PJH site. but its a rubbish Flash site that takes ages to load AND it no
longer shows YP4 but YB8 is there though!
Bubbling decals solution
- see Gary Pollard's solution
After-market
plastics.
You can't get after market plastic for
the TTR except an MX style rear fender. You can put any aftermarket YZ/WR front
fender on it though - just cut off about an inch in the back. These on-line
sites are probably the cheapest places you can order replacement OEM plastic and
OEM parts for the TTR250 in the US:
www.ronayers.com -
www.mrcycles.com -
www.crotchrocket.com -
Maier USA Shopping Online
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TTR250 - Street
Legal in California? (Courtesy of Tommy Vee)
I recently legalized my TTR in California. Baja designs would be glad to
sell you a complete kit to convert your bike but I just ordered the parts that I
needed since the head and tail lights are dual filament bulbs (high beam and
brake lights) and the bike already has an adequate battery and charging system.
You can purchase the turn signals from a local bike shop such as Cycle Gear.
Baja Designs supplied the turn signal/ headlight switch (p/n 12-9005), the turn
signal flasher, and the horn. I made up my own wiring harnesses but if you are
not able to set up your own, I'm sure that Baja designs would be able to supply
the wiring kit also. Be sure to ask Baja for the turn signal wiring diagram for
their switch. For the brake lights, I bought a hydraulic brake light switch from
the local bike shop. The switch replaces the Banjo bolt on the rear hydraulic
master cylinder. Once you have all of the lights brakes and turn signals and
horn set up, check around with the local repair shops as the bike shops will do
the brake and light inspection not the CHP. Call your local CHP office and get a
copy of form CHP 888 as the DMV will ask you if you have read the form and you
must certify that your bike complies with the requirements. Buy some insurance
and rip that green sticker off so you can turn it in at DMV. Call the brake and
light station and find out what they will check for. Remember to install a high
beam indicator light. I bought a 12-volt mini lamp (blue) from Radio Shack and
tie wrapped it to the front brake line guide ring next to the trip meter. Baja
was very helpful you can get their 800 number from their website and call their
technical services dept. If you are pretty good with wiring it should be a piece
of cake. Good luck. TV
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Got a brand new TTR?
A mate imported a pair of Euro TTRs and they arrived in a crate with no
information as to their preparation. Here are some tips that I found through the
internet and from practical experience:
-
try and read the manual to get to know the bike
-
check and tighten any loose spokes - continue to
check the spokes periodically to ensure proper tightness
-
remove front and rear axles and coat with a high
quality grease or copper based "Anti-Seize".
-
check header pipe (rear end) for restrictor
washer and
remove if found!
-
if you can face it, dismantle and re-grease rear
suspension linkages before you use the bike - else you will never do it!
-
dismantle and check kick start, rear brake pivot and
steering head, to make certain they contains sufficient grease in all the
bearings
-
the foot pegs have a particularly high tooth on the
outside which is just right to catch in and tear your leggings - file them
down
-
take off the tyres and put them back into store for
when you need to sell the bike - put on some decent rubber that suits the
conditions YOU ride in
-
Get to know the bike, as far as how it is put
together. Do this by removing the plastics, fuel tank, and whatever else you
feel like doing; the more the better. It is likely that many bolts, nuts,
etc. will be loose, or just not tight enough. Loose bolts can be/will be
discovered while removing the plastic, etc - check all nuts and bolts and
fittings for tightness and re-check regularly.
On new bikes, some
riders hear a strange tinny rattling or metallic whistling noise from the
left-hand side of the engine on the over-run i.e. when you shut off the
throttle in any gear. Steve Copsey tells us that the reason for this is that
where the chain is new and tight it doesn't slip off the front sprocket as
smoothly as it should and bends outwards as it leaves the lower edge.
Basically it rubs against the lower section of the case-saver - take this
cover off and you will see the rub mark. The answer is to file about a
millimetre off and the noise will magically disappear.
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When it all goes wrong!
If anyone knows of a
repair shop that has particular expertise with TTR engines please e-mail me with
details.
In the UK, the Yamaha Technical Hotline number is 01932 358 065 - very helpful
apparently!
Thanks to Terry Oram for the following: "There is a small company called
Vernon Motorcycles in Havant, Portsmouth. They sell and repair all sorts of
bikes mostly imports, and I have found them quite useful as most of the guys
that work there have TTR250 Raids. The number is (02392)498558, It's probably
worth giving them a call as they have completely stripped and rebuilt their
bikes in the past." Anyone with similar personal recommendations around the
globe please let me know.
And to Nik Codling: "Just thought I'd mention the excellent service I've
had from Quick Crank in Waterlooville (02392 233933). This place is great - full
of absolute perfectionists. They specialise mostly in restoring old vehicles,
and re-building or even manufacturing things like cylinder heads and
blocks." They did a good job on boring his cylinder apparently.
Greg Hughes of Taunton, UK, says "I bought my TTR from Riders of Yeovil 01935 477154 after a few weeks it
developed a pretty bad engine problem which was repaired under warranty and with
a smile !!! Tony at Riders seems to have a pretty good knowledge of the TTR."
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