My SP 500 is bogging when I first get on it. I've replaced the sparkplug, belt, air filter, fuel filter, and still it does the same thing. After it runs for a while it'll catch up and go just fine until I stop and it cools off and then it's the same thing all over again. I've put gas treatment in it. The only thing I haven't done that I can possibly think of is the voltage tests that are described in the manual for the stator. Could this be it? I'd think that either the stator was putting out what it was supposed to or not...nothing in between...and even if it was, it'd do it intermittently during the ride. Once it "catches", it goes just fine from then on. This has got me stumped.

 

I'm not sure,but you could try rejetting the carb. depending on the altitude or temps. your riding in.

 

I put the clutch mod from AAEN on and it helped the rpm increase higher for the low-mid acceleration. Not sure about this bogging down your referring to. I have looked into jet changing as well, but don't know much about carbs.
I'll post more when I find out what to do.

 

Check out your fuel pump if its on waranty give it to the dealer don,t mess with it also clean your carb if it is not on warranty and try using sea foam gas additive that stuff works great. Also check the vent hose coming from your carb blow and suck on it a couple of times while revving the motor sometimes it will dislodge dirt in the carb it worked on my 99 500 mag.