Motorcycle Repair: Slow return to idle, throttle cables, intake leak

Question
My wife's stock 1992 Virago XV1100 recently developed a slow return to idle. The rpms hang up significantly if the idle is set at 1000 or higher, less so if idle is closer to 750 or so (closer to stalling out). The dealer replaced the carburetor joints believing there was an intake leak. No better. There are no obvious vacuum hose leaks, the carbs are synchronized, the plugs are cleaned & gapped, and the bike otherwise runs and starts great. Any ideas? Thank you.
HANDALUKE@aol.com

Answer
Hi Harold,

I suspect one or more of the following:

Carburetors are improperly synchronized.
Throttle cables are binding or improperly routed.
Worn throttle diaphragms/springs.

I'll send a few tech files to your email address.

Visit www.viragotech.com for more tech assistance.

Respectfully,
Mark Shively