I just rode my 04' 250 with about 4000 miles on it for the first time in about two weeks. It was having trouble idling but after a few minutes of messing with the idle **** it seemed like everything was ok. The new problem is that if I rev the motor the rpms will rise perfectly but then as soon as I let off the throttle the rpms will stick around 4,000 then slowly fall back down to under 1,000.

I have yet to adjust the valves or clean the carbs because the bike was running fine before this. Any suggestions on where to start to try and fix the problem?

Any ideas where to start y0?

 

Every 4stroke 250 I've ridden was slow to drop in the revs. But maybe I'm just used to fast dropping revs on bigger bikes and 2 strokes.

Can you remember if it has always done that?

 

It's definitely something new. Off the top of my head it takes maybe 2 full seconds for it to drop 4,000 rpms while in neutral.

 

Yeah, that's a lot slower than normal, I would clean out those carbs, just as a start, and go from there.

 

Push the choke all the way in