Project Yamaha TTR 230 Dirtbike More Questions

Super Hunky has finished building his, but the questions just keep pouring in

Jun. 16, 2008 By Rick Sieman


 yamaha dirtbike tech mikuni carbWe have been to 6 different Yamaha shops and can not find 43f-14342-19 #38 Jet, they have no idea what we are talking about and act as if we are speaking a foreign language....please help
Post Falls, ID

Contact:  Mikuni American Corporation
8910 Mikuni Avenue
Northridge, CA 91324-3496
Tel: (818) 885-1242
Fax: (818) 993-6877  or


Or simply go to a good carb shop and have the 36 reamed out to a 38.




 Hey Rick.

yamaha dirtbike tech ttr230 air leakI just recently purchased an 07 ttr 230. it has really low miles and runs perfect except sometimes it just starts reving really high then dies. I think i need to reset the floats in the carb. Is this common with these bikes? Do you have any other advice of what I should do?
Santa Barbara, CA

Nope, it's not common.  I would first check for an air leak, possibly in the rubber manifold.  This would contribute to high  revs at random times.





 yamaha dirtbike tech sprocket gearI have a ttr230 all i did was the back sproket from a 49 to a 46 and the bike gives ayou a better responce and also for long run you can feel your self going faster..... i just want a better suspention....
biger tank..... and front light for night life.....
San Diego, CA

By going down three teeth on the rear, it was almost the same as one extra tooth on the countershaft sprocket.  If you  really want to see a difference, try the stock rear sprocket and go up two teeth on the c/s sprocket like we did on our project bike.  We plan to do some lights later in the project series.






I've done the carb mods and the gearing mods and it made my bike a lot better, but every time I get in sand I'm all over the place.  I've only been riding ayear or so.  What's the deal?  Is the bike just bad in the sand or am I doing something wrong?

 Charlie Watts

Simi Valley, CA


yamaha dirtbike tech ttr 230 tiresThere's nothing wrong with the basic handling of your bike, but the stock tires really suck in the sand.  Also, when you turn or change direction, do it with the power on.  If you turn in sand with the power off, the front end will dig in and plow.






yamaha dirtbike tech backfire screenThere's piece of screen wire kind of thing in the airbox in front of thefilter.  When I was cleaning out the airbox and the filter I lost this piece.  Is it OK to ride the bike with this out?

 Randy W.

Jacksonville, FL


That "thing" is a backfire screen and we took ours out. Enough said. Newsletter
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