Ok, well Im usually the on giving the adevice on these forums, but this has got me completely stumped. Ive got an OFNA Hyper 7 PCR with a Novarossi T21BF engine. Ill go out run it for 3/4th's of a tank, take it in, check temp, adjust needles if necesary, ect. Then everytime I go to re-start it it will never go. I check the plug and oh, that's my problem... It's dead. I'll replace it with a BRAND NEW SEALED PLUG. Do the same thing bring it back in try to start it, and it won;t go, I'll check the plug, and what do you know... it's dead. I tried again thinking maybe I got a bad plug or somthing. Same exact thing happens bring it back in, it won't sart and the 2nd BRAND NEW plug is dead. It isnt the usual running too lean (it's running perfectly, and temps are right were they should be around 240-250). So I went through 2 brand new plugs and another with only a couple tanks through it. I've been having this problem with this buggy for a long time. THe only thing I can think of is that Im running a medium plug, which should be fine becuase Im using 20% but i guess a cold would be a better choice, still I doubt that's the problem... any suggestions?