1980 GS850 Stuck Throttle

[Guest]

I have a 1980 GS850G that when ever you touch the throttle when its warm, even if its a hair, the throttle jumps from idle which is 1000rpm to 3000rpm and it stays. The only way to get it to come back down is to shut the bike off and restart it. I have replaced the carb and intake orings and boots, replaced all vaccum lines and hooked them up correctly, lubed the cables, cleaned and dipped the carbs and made sure they were at stock settings, lubed all the carb linkage, resynced the carbs and adjusted the valves. Is there anything that I am missing, or that I can do to fix this issue? I was thinking my next step is to spray carb and choke cleaner around my boots and other vaccum lines to see if I might have a vaccum leak. But other than that Im stuck. Any help would be appreciated. Thanks

[bikemtn]

Sounds like you are still running lean some how.
Fuel pilot should be 1 to 1.75 turns from lightly seated and the idle air about 1.5 to 2 turns out from lightly seated.
You can richen by turning fuel pilot out. Turning idle air screw out will lean the mixture.

[bwringer]

Sounds like you are still running lean some how.
Fuel pilot should be 1 to 1.75 turns from lightly seated and the idle air about 1.5 to 2 turns out from lightly seated.
You can richen by turning fuel pilot out. Turning idle air screw out will lean the mixture.

OP's bike has CV carbs, not the VMs with the separate fuel and air screws.


In any case, yes, look for vacuum leaks, clogged or leaking choke circuit, and assembly errors.

[R3v413]

The only vacuum leaks that I found were due to loose clamps. The choke circuit is clear and leak free. I did end up adjusting the throttle cable a little though while I was at it. So with tightening the loose clamps and adjusting the throttle cable, my problem has seem to gone away. Thanks for the help, its much appreciated.