Any carb experts here?

[blong]

I just got an EX250, but it isn't running very well. First off, it has a bit of a dead spot from 6-8k RPM.

The bigger problem is that it idles around 4k. If I'm super gentle with the idle adjustment I can get it to idle at 800 RPM, but if I blip the gas at all, it'll jump back up to 4k. Plugs look lean. I tried screwing out the pilot jets, didn't really help. So, I figured it had an air leak so I got some starter fluid and sprayed the carb over while it was running to listen for it reving up...nothing.

Interestingly, my buddy with an old GS500 has the exact same problem.

[Termin8r]

Here I thought I was going to get some diet tips from this thread.

[r1brip]

that definitely sounds like an air leak problem, my dirtbike had that happen to it twice. Inspect the rubber manifold between the carb and the motor really carefully, even pull it off is its not too hard just to double check it

[Jakub]

To inspect the manifolds just put your hand around them while the bike is running. You should feel a leak.

You can also take the carbs off and take the floats bowls off, then spray all the passages with carb cleaner. Not sure how your carb is, but I just rebuilt the one on my ZX and it was really simple.

[blong]

I replaced all the vacuum hoses on the carb. The manifolds looked great. I cleaned out the carb again. Same problem. :cry:

Open to ideas if anybody wants to share.

[Jakub]

When you took the float bowls off, how did everything look? Might try taking the jets out and cleaning everything really well, and blowing compressed air through all the passages.