250-500cc Stator problem 2008 WR250?

I was out riding a few weeks ago and my WR250, and after about 4 hours of riding the bike started to stumble after a about 3/4 throttle; it had been running fine. I changed the plug and it continued doing the same thing.

Took the bike out to check jetting last weekend and the stumble issue moved to 1/2 throttle and up. Luckily a riding buddy was sitting in the parking lot and noticed that my headlight was pulsing even at higher revs... So I disconnected the reg/rec (aftermarket to run DC) and the bike ran great. I plugged the reg/rec back in and bike again had the same stumble.

I was messing around in the garage yesterday; hooked up the stock reg and wired up a temp harness to eliminate the reg/rec and the harness. No go, bike did the same thing. I checked the lighting coil open circuit voltage (regulator disconnected) and it varied between ~11-13V when the bike was idling ~1800-2000 rpm. I checked frame grounds at the ground stud near the coil and they are tight and not corroded. Checked the 4-pin plastic connector and it was seated.

I took the plug cap off and the resistance measures 4.7K, so I would think that eliminates the plug cap as a potential issue.

At this point my thought is that it is a bad stator or possible a fault in the stator harness. I have a spare stator that I am going to put on the bike, as soon as I figure out how to get the flywheel off. The puller I got from the dealer is a bolt style.......


Thanks in advance


Edit: Okay; things are going "well".... just messed up the threads on the flywheel (not the crank). Took the bike to a local shop to have him remove the flywheel... Gave him a spare puller (kind with the tapped thru hole) I had lying around for a different bike. He'll probably weld it to the flywheel etc... Called Halls and bought a different style flywheel puller (one that has the tapped thru hole).

what's the thread size of the flywheel puller for your bike?

i have the same bike and need to remove mine but am not sure which puller to buy.

thanx

I believe it's a 22m x 1.5 RHT. I ended up calling Halls and buying the Husky puller, I don't think it was much more than the aftermarket. The aftermarket one I had was the type that you have to put a ball bearing in; I like the Husky one much better...

thanx. taskys is getting them in in a couple of days. i'll just wait vs. ordering.