cutting out on the top end

[farmer250r]

ive got a 87 trx250r with a pwk 38mm carb.its cutting out on the top end,bottom end seems fine,rips on the bottom end,but keeps cutting out.ive checked the piston and rings,carb looks fine.do i need to clean or rebuild my carb,or is somthing off?

[fearlessfred]

it could be as simple as to large of a main .post your main size,elevation and weather conditions and someone can give you an idea if your in the ballpark

[wilkin250r]

Could be unrelated to fuel/carburation completely, could be an electrical issue. I've seen flywheels get dropped, and crack the magnets inside.

The stock 250r ignition gets weaker in the high RPMs. A cracked or otherwise compromised flywheel could be just enough to push it from the arena of weak, to the arena of non-functional at high RPMs.

[farmer250r]

it runs good at low rpm's and at idel.its only when i realy get on it on a straight away and im building rpm's i can spin the tires into high rpm's,but on the straights,it wants to cut out,no when i pulled the carb apart the needle droped out,the clip was still there inside so i put it back in there and it seemed like it was saying and also cleaned the carb while it was off.im in nj,so im about sea level,and weather is around 65 right now.my jets dont seem to be off cause this just started to happen,it ran good for the few weeks i was riding it,but it just started to cut out on the top end,i love this quad to much to get rid of it (made the mistake of selling my last one) so im fixing this one no matter what!

[C-LEIGH RACING]

Stock ignition system ??.

If so, set the plug gap at .018 to .020 & see if that helps.
Neil

[farmer250r]

stock ignition too,the plug is brand new so?

[danhung11]

Originally posted by farmer250r
stock ignition too,the plug is brand new so?

Gap the plug properly like Neil said, that's the easiest cure. I've seen brand new plugs all over the place. If that's gapped at .018, I'd move to the main jet. Then proceed on.

Need more info on your setup like wilkin250r said...

[farmer250r]

what do you guys need to know? im here to learn! so tell me wht ou need to know and ill get the info for you.heres what i know so far.
carb-pwk 38mm
eleveation-sea level
igniton-stock
im gonna go check mt main jet and see what it is.and check the plug gap.ill post that all up tonight