I don't ride very hard, so I don't get to WOT very often. I decided to do a quick test in my driveway after I got home from work today.

I parked the bike and cranked the throttle wide open. A couple of odd things happened:

a) It didn't run smoothly at WOT
b) Slight smoke from exhaust
c) Exhaust picked up a funny smell

Is running the warmed up engine at WOT when it's parked a valid test?
Based on these symptoms, what do you think the issue is?

-D. Dwarf

It has been reported that an electronic rev limiter exists in the CDI box. If so, it works by cutting out some of the sparks when the engine exceeds the rev limit. In turn, this will cause the engine to run irregularly, and will cause the unburned fuel (unburned because some sparks were missing) to make the exhaust smell different. Under no load the engine can exceed its rev limit, when it would not do so in gear under load. The engine might reach its rev limit in the lower gears.

Fuel injected engines with rev limiters usually work by cutting fuel delivery rather than ignition. Cutting fuel delivery causes no unburned hydrocarbon air pollution, while cutting ignition allows the fuel to go into the exhaust pipe.

What is wot?

Wide Open Throttle - WOT. I have also seen WFO, and I am not exactly sure what that means (yeah, I know - wide open). It is usually considered inadvisable to run engines wide open with no load, because they can be damaged. Electronic rev limiters reduce or eliminate the chance of damage. Rev limiters cannot protect against overspeeding caused by mistakes such as downshifting at too high speeds.

That's a quick way to blue your header.