GS500 Engine Troubles

[ac_nvmax]

Ah my beloved GS still hasn't been fixed. I fixed the problem with fuel (no spring in the vaccum / tap causing fuel to flow when engine off, ouch).

Anyho'. Acceleration is still poor and general tickover is haywire. Max speed about 80mph

If I unplug the left start-plug lead the revs are going up and down and doesn't sound good at exhaust, like minor backfiring. Not smooth running.

If I unplug the right start-plug lead the left cylinder is running smooth EXCEPT if I rev to say 6000rpms and hold it there while in neutral the rpms constantly become lower until the engine dies.

The only thing I havn't had checked yet is the valve clearances. Does anyone know if this could cause any of the two problems?

Please help my poor GS this Christmas  :kiss:

[JamesG]

Yes check the valves.  Such different behavior between cylinders means there are leaks or your carbs are way out of sync or tune.

[ac_nvmax]

Thanks, I had the carbs tuned recently but I had to readjust the right carb needle as it was too low and no fuel getting through. Could have upset the balance.

Andy.