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Hi all - I'm working on a 1980 yamaha xj650G maxim. I finally fired it up again after years in the garage. I removed & cleaned the carbs before doing so, but it seems I have a few of the same problems I had years ago. It doesn't idle correctly, sometimes revs high for a long time, & back-fires often. Could this be due to the carbs not being synchronized? Something is also wrong with the throttle cable itslef, when I move the cable with my hand, it revs up. I had to remove it from the clip because at times when I'd turn the handle bars it would rev up then too...?? Any suggestions?

Thanks in advance.

Rj

The engine revving with bar movements or by moving the cable is just because you don't have enough slack in the cable, it's adjusted too tightly. You should have a slight amount of freeplay at the throttle grip at idle, so that you have a few (very few) degrees of twisting movement before the cables start opening the carbs up.

Carb sync can cause bad idle, but since your bike has been sitting, it's probably best to strip and thoroughly clean them, and then get them sync-ed.