Question for the carb gurus...

[Anonymous]

Every once in a while, when I rev my motor (850) at idle, the carbs will give a quick "spit" before rpms climb. And sometimes the rpms will "hang" for a second before dropping back down, and when they drop, they go below normal idle for a few seconds before recovering. I'm thinking this means lean, am I correct? I've checked for vacuum and air leaks with both carb spray, and starting fluid, and can't seem to find any leaks.

[Jeff Tate]

I'd say you're on the right track as far as being lean goes. Is your motor stock? Have the carbs been off and cleaned? if so maybe some loose dirt clogged a jet or orifice. If not it might just be old age causing the rubber boots to stiffen and not seal right. Happens to the best of us. I think you're looking in the right direction anyway.

[focus frenzy]

what year model is it? pre 80 bikes had slide type carbs, and 80 and later bikes use CV type carbs.

[Anonymous]

what year model is it? pre 80 bikes had slide type carbs, and 80 and later bikes use CV type carbs.

It's an '83, with CV carbs. Kind of weird that it would start running lean though. The only thing I've changed is the airfilter. I did put in a Uni, and removed the backfire screen from the stock airfilter. But that shouldn't lean it out all that much, or should it?

[KEITH KRAUSE]

what year model is it? pre 80 bikes had slide type carbs, and 80 and later bikes use CV type carbs.

It's an '83, with CV carbs. Kind of weird that it would start running lean though. The only thing I've changed is the airfilter. I did put in a Uni, and removed the backfire screen from the stock airfilter. But that shouldn't lean it out all that much, or should it?

By changing the filter and removing the screen you have made the intake less restrictive,you will draw more air through the side air screw. Try turning them in 1/2 turn to counter this and re-set idle. Repeat if necessary. If they have never been disturbed, they can be stiff. Use a good fitting screwdriver. I'm not too familiar with CV carbs but are the diaphragms 'ok'? KK.