Yamaha TTR250 FAQ - Updated 24 August 2001
The TTR is a very civilised traillie that TBM described as being "as civilised as it is competent". Only a handful of TTRs was imported back in 1995 by Mitsui Yamaha (were these classed as "official" imports does anyone know?) but 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 are basically two models: (pre the Y2K "blue" model) the Open Enduro and Raid. 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" 2000 TTR (plastic tanks) became available and sold officially by Yamaha in the UK. The 2000 models have electric and kickstart making them "dual start" as well as revised steering geometry and suspension. Some of the common parts are interchangeable with other makes of offroaders, i.e. brake pads, but the battery is peculiar to the TTR (and expensive).
How much should I pay for a Yamaha TTR250?
What should I look out for?
What gearing should I use for the Trail?
What tyres are best for on and off road use?
Can I get a big-bore kit for the TTR?
Yep! Paul Bates of Bogbusters
International Imports is building a 320 - watch this space! Brian Eland
of www.BrianEland.com is also
looking at importing SRC big-bore kits. Also, have a look at this American
website for tuning stuff for TTR250s - 325 big bore or 350 stroked
kits have been available in America for some time - http://www.strokerspeed.com/bikes/ttr250.cfm and http://www.srcinc.net/enginekit.html
Rumour has it the 350s can be unreliable though :-(
325 big bore or 350 stroked kits have been available in America for some time - http://www.strokerspeed.com/bikes/ttr250.cfm and http://www.srcinc.net/enginekit.html Rumour has it the 350s can be unreliable though :-(
Can I get a bigger tank for LDTs etc?
How can I improve the lights
on the open Enduro?
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).
Can I get second-hand parts for my TTR?
Can I modify the exhaust to improve power?
(a) 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.
Setting up the carb to match the exhaust. It
is possible to re-jet the Teiki carb using Kiehin jets. What to use
depends on what year your TTR is. 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. Johnny's 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:
(c) Martin Wilson's TTR had an XR400 tail pipe 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.
What brake pads fit? (Info from Paul Bates
- thanks mate!)
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 should be able to drop the brake pads down then remove them backwards. On installation to put the pins in you have to push slightly up against the anti chatter springs, Copper Slip the brake pins very well and only tighten very carefully - if you over tighten the pin will stick and it will have to be drilled out - any doubt about the fit of an Allen key into the brake pin do not put it back in - replace it instead.
Oil filter is a common off-the-shelf Yamaha
part - I used a Champion X313 last time around (Yamaha Part No is -
Where can I get a manual?
a) The guy to contact for a 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. Or 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
Wheel Bearings. 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. Yamaha uses very good bearings and are worth paying the extra for. The bearings for the TTR250 rear wheel are: 60/22RS and you need 3 of them.
Rear suspension linkages. It is recommended that you take the rear suspension links apart every year and re-grease the needle bearings with good quality lithium grease. The TTR linkages are very well put together with almost all links having their own grease nipples. I stripped mine down recently - probably the first time its been apart since new (6 years ago) - and everything was in excellent condition apart from one split seal which needed replacement.
Clogging of front sprocket. 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 on the Yahoo Group - address at top of page. Looks simple but effective. The Y2K TTRs have a conventional speedo driven by a front wheel cable so don't suffer with this problem!
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.
Further TTR links:
http://126.96.36.199/Yamaha_OEM/YamahaDB.asp?Type=12&A=171 - Ronnie's Microfiche On Line - although for the 2000 TTR250, most parts seem remarkably similar to my own 1995 model - worth a look!
- Ozzie TTR project - the 2000 model really is competitive!
http://www.members.home.net/jcorsaro/ttr250.html - Jeff Corsaro's TTR250 pages - American site - Jeff has pics showing how to convert a Y2K TTR250 for on-road (dual sport?) use. He should be putting some more stuff on the site soon so re-visit it occasionally.
http://briansussex.btinternet.com/TTR250pics.htm - pictures of Rides List members TTR250s and any other good ones I can lay my hands on - mail yours to me for inclusion - my e-mail address is below. Some additional pictures are in personal folders on the Yahoo TTR250 Group in the "Files" section.
http://groups.yahoo.com/group/group/TTR250 - A one make/model list for TTR250 owners and enthusiasts to exchange questions, answers, information, and advice.. Any one is welcome to talk about dirt and trail bikes, SuperMoto (?) TTR250s, tuning, racing, maintenance, practice tracks, trails, events, and any other TTR250 - stuff.
Paul Bates of Bogbusters International Imp Ltd (e-mail email@example.com) and Brian Eland of www.BrianEland.com (e-mail Brian@BrianEland.com) are very knowledgeable on TTRs and can provide good advice and the all-important tune-up bits. They both subscribe to the TTR250 Group mentioned above.
A little extra pressie at Xmas? A nice little 1:18 scale die cast model TTR250 is available from Hachette in issue 14 of their Mega Bikes fortnightly series - cost a measly £4.99. Obtainable from their Customer Service Hotline - 0870 7297290 (Mon - Fri 9am-5pm).
TTR250 FAQ compiled by Brian Sussex
Please check his site at www.briansussex.btinternet.co.uk/ttr250faq.htm with any suggestions for updates, corrections or additions