YZ125 Compression Problem

I ride a 2004 YZ 125 and had my top end rebuilt this week, we put a wiseco piston in, while we were doing the top end we also put vforce3 reeds and a FMF SST pipe. The bike ran fine before this, and after we put the parts on and dyno jetted the bike it holed the piston at 4400 rpms on the dyno. we put a stock piston in it checked the timing, and after every dyno run we checked the piston for etching. We made a few runs and the bike was running a little rich, we put it up to 5000 rpm's and the bike started to sound funny so we pulled in the clutch and checked the piston sure enough it had started pitting. i just dont understand how a expansion chamber and reeds can up the compression. If any one has experienced anything like this please tell me, but what is going to happen is i am gunna have to run race fuel. If anyone has any recommendations of what type of fuel tell me. I found out this bike runs borderline on 95 octane out of the box but i have had no problems running the engine for 2 years on 91