Cutting out at high rpm's
So I picked up a yfz a while ago and it ran great and the power felt good throughout all the gears. I put a new HMF exhaust on (already has fmf head pipe and no intake box lid) and jetted it myself and it ran great minus some exhaust backfiring. so a couple weeks later i decided to try to rejet to see if i could fix the exhaust popping, then I started experiencing problems with it cutting out in the higher RPM's. I have tried at least 30 different jetting/fuel mixture setups on it and different brands of jets with no success. And that's when I decided to let the pro's handle it, At least that's what I thought they were.
So 18 days later I got a call from the shop saying my YFZ was ready to be picked up. went to test drive it and it still cuts out on high rpms throughout all the gears. The Carburetor has been rebuilt, new carb joint, every seal has been replaced and new exhaust gaskets. $400 later it still runs like crap.
I told them I wasn't happy with it and it runs worse than when I brought it in. Then the mechanic somehow magically knew that it was the spark plug cap and told me they would try to see if that fixes it, so I said whatever.
I was originally told the price would be no higher than $200. do you guys think I should pay the $400 when the bike runs the same way as before? I understand they put new parts on and rebuilt the carb and that did make it feel smoother/more responsive. But my original issue has still not been resolved.
I'm going to pick it up in the morning and fix it myself. I have done some research and it sounds like it could be TORS, bad coil or stator going bad. I am positive this is not a jetting issue.