91 Rm250 bogg

[vettett15]

hey guys, im working on a 91 rm 250 that doesn't have any low or mid range and will only clear up when in high gear and rev'd out. low and mid range it just trys to cough through it, noticed some oil coming from the powervalve vent, only known mod is an fmf full exhuast. any help is appreciated
pete

 

[Nice Guy Eddie]

it may well be jet related.... do a search... lots of good info

 

[Studboy]

Or a right side crank seal (drawing in tranny fluid).

 

[darringer]

I second the tranny-side crank seal leaking. The rm's of this vintage were notorious for crank seal leaks. Does it smoke excessively? That's usually a dead giveaway.

 

[vettett15]

hey thanks for the replies, no it doesn't smoke more than it should, some of the bogg cleared up and now it just has a low end- mid range bog in the lower gears. We put a 380 main jet in it and a 45 pilot jet and the needle is 2 down from the top. i took out the reed too and they are a little chipped and didn't seem to seat well so i switched them and they seat a little better, could this be it. any jetting tips would be great
thanks
pete