1981 GS 1000 GL won't run

[Anonymous]

I recently bought a 81 gs 1000l. The bike has about 15000 miles and is in very good condition cosmetically. I didn't have much info about the mechanical condition, but it was supposed to fire on either. I cleaned the carbs thoroghly, replaced the battery, and intake o-rings. I will run, but won't idle and is hard to start. Above 2500 rpm, fully warmed-up it runs strong. Valve timing is in line, 6 of 8 valves seem too tight (<0.0015), spark seems ok. Compression is 125-140 across the board. Right now I am where I started. I will run on either. Are the valves the problem?

Any Ideas????

Thanks,

Jack

[Anonymous]

try putting your petcock in the on or pri position and see if maybe the vacuum is not working on your petcock otherwise you have me stumped but I don't think it can be you valves if it does run above 2500 rpm.

[Dink]

try re-cleaning the carbs paying particular atention to the idle circuit and the choke circuit, the behaviour you describe is reasonably common if these areas need further attention, as a blockage in either area will starve it for fuel at the RPMs you mention, and hence it wont idle.
Dink
BTW it wouldnt hurt to check and clean the petcock(fuel valve at the tank) just for preventative maintenence sake.
Dink

[Motorcyclemodeller]

I agree, carbs!

Sounds like a plugged or obstructed pilot jet, check the filter in the tank, condition of the interior of the tank, fuel petcock. Basically check over the whole fuel delivery system.
You can switch to clear fuel lines, this will allow you to check flow, an inline secondary fuel filter won't hurt either. I use a clear glass one, it allows you to detect any sediment or crap coming from the tank; with a quick visual inspection.



Hope this helps,

Dr. Dre