Backfire.. No start.

I think the idle will settle down as the WD-40 is drawn into and temporarily seals the air leak. Smoke a little too, then it goes back to what it was doing before.

I heard also it could be junk in the carbs from sitting... I don't have internet at my house so I try to get as many ideas and post as much information as I can before I go home to work on it. So I heard sea foam, or disconnect the airbox from the carbs, run the bike and cover each air intake and give it gas, if gunky carbs is the problem. Is that a good idea?
-Ed

CptEDIV wrote:

...its doin a funny thing it used to do, when I give it gas, the RPMs go up and stay for about 2-3 seconds, before returning to about 1, and then idles rough. I can start it, get it to a good sound idle at 1- 1 1/2 RPM, but if I rev it, it stays up then when comes down I have to set the idle higher or constantly give it a little gas to keep it running....

Has operation of the ignition timing advancer unit been checked with a strobe-type timing light to assure quick return of advancer to idle position when throttle is closed?