XR250 problem again, missing at top end

[B0000M]

once again, my mate damo who is too proud to ask anyone (so ill ask for him) is having problems with his 96 XR250, it has a miss a the top end of the rev range.

so far:
spark plug has been replaced
fuel has been replaced
carb has been cleaned out.

any other ideas?

also, in the left side cover, in front of the front sprocket, is there meant to be oil in there on an XR? usually this is a dry area on bikes ive owned where the flywheel chills out with the magneto etc or all that electrial crap that makes the bike miss when its damp, so is it normal to be full of oil in there? (quite a lot od it)

[merv]

It is normal on the 4 strokes for the alternator to be in where the engine oil is so no worries there.

However with a miss you just got to keep trying trace it - could be plug lead, CDI or anything like that. You say you've cleaned the carb out so shouldn't be that but worth checking again.

[grantman]

You could also try changing the spark plug cap and HT lead
it maybe shorting or breaking down.

someone had changed my sparkplug cap and it used to cut out when wet
(then the heat from the engine would dry it out and it would fire into life again..took a while to find it)