Sticky Throttle?

[Anonymous]

I just fixed up a 1977 GS750. It runs pretty well, except that when I'm riding it and come to a stop light, the rpm's stay at about 3K. When I first start it, it will idle just fine at 1K. When I park it for the night, it will have itself revved to 3K when I hit the cutoff switch, but in the morning it will idle again at 1K. I lubed the throttle cable and made sure that the carb slides are clean when I rebuilt it and stuck it back together. Any suggestions as to the problem?

[Billy Ricks]

This may sound like a stupid question, but have you adjusted the throttle stop? Are you having to use choke at startup to get it to idle a 1k? Do you have a little slack in the cables? If that's all okay you may have an intake leak.

[Anonymous]

thanks for the idea

i did adjust the throttle stop. there is slack in the cables and the choke is off when it idles at 1K. is an intake leak the only other possibility? i did check for intake leaks, but not that thoroughly. i'll check again, thank you

[KEITH KRAUSE]

Classic intake leak. Most likely the manifold o-rings, less common the manifolds themselves. Check manifolds for any cracking/hardness. Almost certainly the o-rings need replacing.

[jhw84]

My GS would rev up after it got hot because I had a sunken float. If youre floats are brass, old, or have been replaced recently, check your float level.

[KEITH KRAUSE]

My GS would rev up after it got hot because I had a sunken float. If youre floats are brass, old, or have been replaced recently, check your float level.

I don't see how a punctured float, resulting in too much fuel in the bowl, could cause a high idle as he describes.
Not arguing, just my opinion.

[Billy Ricks]

Spray around the intakes with WD-40 and see if the idle changes.