Racing tomorrow and NEED HELP QUICK!

[Tom TRX250R]

My R is sputtering at top end. My main jet was at 175 so I tried 168, 172, 175, 178, and 180. I messed with the needle position and still not running right at top end. I replaced the coil and still the same issue. I don't know what else to check. Could reeds cause this? Any ideas of what I can do to solve this problem?? I am racing flat track tomorrow night for the first time and I want my R running up to par. PLEASE HELP! Thanks

[wilkin250r]

Is it always sputtering? if I let mine idle for a while, it would sputter for a good 20 seconds at WOT until it cleaned itself out. and then ran fine.

Also, I couldn't rev it in neutral to clean it out. I actually had to ride around.

Beyond that, I my first suggestion is that you might still be rich. Have you run a plug chop? When you put the 168 in, how long did you ride? Did you give it long enough to clean itself out?

[Tom TRX250R]

It was running great but it sat for a few weeks then I went to a local riding track and it had no top end. It would sputter out. When I put the 168 in I rode it up the street for a minute or two and it wasn't running well at all. I tried all the adjustments on the needle with that main jet too and still no success. Could it be the pilot jet? Any help is appreciated. Thanks. Tom

[wilkin250r]

The pilot jet shouldn't have any effect on the top end.

How long did you ride it after it sat for a few weeks? I'm thinking that maybe after sitting, you had fuel puddle up somewhere, and it hasn't cleaned itself out, yet. That's my first guess.

Diagnosing a "doesn't run well" can often be difficult, especially if you don't have the right tools. Have you done a compression test? Checked the reeds? Leakdown test?

If it ran okay once, before it sat for weeks, then my first suggestion is to get a buddy and go riding (the buddy is to help tow you back if it dies, so bring a tow rope). See if it cleans itself out and starts running properly again. Make sure to check the radiator fluid level, oil, things like that before you go.

If it still doesn't run right, start the diagnostics. Compression check, check the reeds, leak-down test, plug chops, ect...