Coil mod? Testing coils?

I'm wondering if the ignition coils are not delivering a good spark at high rpm's. Does the engine do this running on the centerstand in neutral?

Tried a different brand of sparkplug? I've had NGK's fail right out of the box and fail sometime later, starting the endless chase or what it could be: ignition coils,fuel delivery,low compression & mis adjusted valve clearances.

The bad thing is the center stand was missing when I got the bike. I wish I knew why someone removed it. It runs fine idling on the kickstand, running at a stoplight, accelerating up to the 5000rpm area. After that is when it starts to flutter. 1st gear at 5000rpm or 5th gear at 5000rpm it acts the same.
BTW: The exhaust/megaphone exits on the left hand side of the bike, where as all other exhausts exit on the right for these bikes. This may have something to do with why the center stand is missing.

Even though the spark looks good I'm going to try a new set of B7ES plugs.