Trouble with higher revs on 250r!!!

[trx250rrider]

When riding, when I punch 3/4 to full throttle in any gear, it bogs down and loses speed. My quad only goes about 60 now down the road instead of about 75 what it is suppose to do. When throttle is pegged or almost pegged, it misses, sputters, and loses speed. I'm guessing maybe my main jet is clogged??? I don't know. At first I thought it was my plug. Replaced them twice and got the same exact symptom. Even though I need to rejet my carb because it is rich as I've known for a while, this is a new problem other than my jetting. But hopefully it is a clogged jet or something related in the carb. Has anyone had this problem before on their quad? Thanks for any help from guys.

[trx]

its running rich and what size plug are you running

[trx250rrider]

I am running a B8es right now. I was running a Br9es and a Br8es. I've been running rich for a while but have had no time to tear the carb apart. But the problem with my quad not reving up at all at full throttle just happened the other day. This is a new problem of mine other than it being rich. Maybe the main jet got clogged or something....... I don't know. Hopefully someone has an answer. Thanks.

[ky 2stroker]

yea the main jetting being pretty rich will cause this, but it could also be an electrical problem like a weak ignition. how strong does the spark look when you ground out the spark plug and kick it over?

[1upfront]

Is it a miss like sputtering, or is it bogging, we need you to be more specific this would help in determining what the problem is, and also have you done any plug chops because if a 2stroke is bogging at wide open throttle that usually is a sign of a lean main jet but if it is sputtering or breaking up it's probably rich.

[trx250rrider]

It is bogging down when almost wide open to w.o.t. Even though you said that if it was bogging down it might be lean BUT, I highly doubt it is lean. My plug has been jet black and wet everytime I change it out. I'm not trying to argue with your point, but, I really do doubt that it's lean. But I could be wrong. I will eventually take the carb apart and see what size main it is in it to have some information to start by. If your thought about the main jet being lean is correct, then maybe it is my needle jet or my pilot jet that is richening the plug up that bad to where it won't change colors after it gets that black. Maybe you are right, but I do want some more opinions about this problem. Thanks very much for your input and your time in answering to my post. Please post some more though. Even opinion is greatly appreciated.

[kildea250r]

I just went through the sputters with mine yesterday. I installed a ported cyl. with already installed pipe/silencer, and filter. Thought a 172 main for a start, sputters at wot, but great response 1/8-3/4 throttle. This morning I installed a 160 main and have the needle at 3rd from top. Runs perfect, much better than the 155 I had in.


My point is that you NEED to look at what you have on your bike now and let us know. Then we can direct you which way you need to go.