my foot is begging for help!

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  • mdechow13

Posted March 01, 2014 - 03:55 PM


I have a 2008 yzf450r. I noticed a couple months after I bought it (used) there was a rattle noise in the heads. Thinking it was the valves needing adjustment I took it all apart even the cylinder just for peace of mind. Well luckily I did. The cylinder was pitted at tdc... Assuming p.o. kept replacing rings ignoring piston out of spec. So I bought a genuine Yamaha cylinder and replaced 3 valves out of 5 valve system(cant remember which ones but they had slow leak). I bought a new timing chain, Gaskets all that good stuff and my gal surprised me with a brand new pro circuit piston for my b-day. and since I had it all apart, I port and polished the head on it. Go big or Go home. I Installed it all, adjusted the valves. the bike started right up ran it in the garage. Shut it off and it started right up. Well I guess it didn't reach operating temp because when I finally took it to my buddies farm trail riding and it stalled in the woods. TOOK ME FOREVER TO START IT BACK UP. I kept taking blows to my foot and said screw it... i'll let it sit. It cooled down and it started right back up after a few kicks. Took it home home, did some research and assumed I messed up with valve spec not having a good set a feeler gauges. re-adjusted them. they wasn't off by much. pulled my sparkplug and it is running super rich. I put a new one in it just to ride it for the weekend and took it back out to his farm. Still same problem. Should have took my "There's your sign award" Its the carb. I have Pro circuit exhaust, Port and polished heads, Pro circuit piston. and I think that's it top end wise. I'm pretty sure it was tuned for exhaust but I guess typing this made me realize a new performance piston and port and polish job is quit a bit to ignore another tune lol. What jets and adjustments do I need for this carb guys. I appreciate it

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