With your bike at idle, spray carb cleaner in places where a leak is possible.
If there is a leak, that spray will get sucked in and cause your engine to rev
up.

Good luck.


--- In yamahaownersclub@yahoogroups.com, "madmxx22277" <madmxx22277@...> wrote:
>
> Hello all, I've been fighting with this yamaha for a long time now, under
throttle it runs good and has good power, but at an idle, it some times revs up,
around 4K or so, and the only ways to bring it down is to slip the clutch... I'm
thinking some sort of a vaccum leak, but have been unable to find it, I've taken
the carbs off numerous times and blown out passageways and orifices... any help
would be appreciated, it is a 82 XJ550 Maxim...
> thanks.
>