help a brotha' out.... rm125

[Dirt Addict]

i just picked up this 03. it looks like it was hardly used. all the tell tale signs are good. its already jetted like fmf, transworld and others recomended.

today at lacr the bike would occaisionally cut out at hi rpm's. it would falter, i'd back off the throttle, rev it some more and it would be back to normal? it seemed pretty random, but only while accelerating at hi rpm's.

any ideas?

btw ive got a top end kit on the way so i will dig in to it soon.

[crider400]

do you meen bog out? Or just like its going to die? Is the jetting in the ballpark? Start by cleaning the carb and passages, check the reeds

[Dirt Addict]

its a falter like the engine is either fuel starved suddenly or like the kill switch is being activated?

hmm i wonder if there is a short somewhere? but it was only during hard acceleration..

btw, this little bike is sooo much fun to rail around turns and do faux scrubs. like a mtn bike with a motor.

[crider400]

check the black box and see if its loose, could shake around and case this also

[Dirt Addict]

cool thanks. i'll ck it and follow the wires too.

[willyd465]

i have had this problem on my rm 125's, i found that the spark plug wire would come loose and not stay on the spark plug, so take needle nose pliers or screw drivers and put them in the spark plug cap and pinch it closer together so it grips the spark plug tighter and doesnt come loose or in a worse case scenario come off on the lip of a jump (fyi... doesnt end well ?)

[Dirt Addict]

willy it was a close call a couple times... approaching a jump hard, then suddenly dying, then coming back on the pipe. i was able to roll it everytime but kinda scary. there is a big step up at the track, 5th gear almost pinned, on my 250. it would be close in 6th pinned on the 125 but i didnt want to risk it till this is sorted out...

[moto_xmayhem21]

That's scarry Bro. I hate that feeling! Sounds more electrical to me (no expert) but the carb is getting consistand fuel feed right? Or it wouldn't come back on? Damn, guess it wouldn't hurt to clean out the carb or rebuild it when you do your top end.