i was having problems, well not really problems last year with popping out the exh, i was continuously leaning my kits all last year, finally pinched a ring at the end of the year. Well upon rebuilding the engine, i have found that the bronze gear on my oil pump drive is worn big time. So much that you can move the rotor back and forth almost .125 !!! Needless to say, when you put a timing light on it, it retards about 6-8 degrees as you increase the rpm. Now this may not have been a bad thing and caused any harm to the engine, BUT now i know that when i replace it , the timing will be where its SUPPOSED to be. SO im going to lean it out, spread some jets and see just how fast i can go this year....
Thankfully the timing was RETARDING instead of advancing LOL...well the gear is only 15 years old, dont they last forever????