I just finished installing a Cylinder Works 256cc Big Bore kit. Timin was spot on as I double and triple checked all timing marks during install and before I put the valve cover back on. Checked all valves and they were good, exhaust was .009 and intake was .005. I also replaced the jets while it was apart, changed main to 175 and pilot to a 45 and placed the needle clip 3rd from the top on a stock needle. That was all I changed and bike is very hard to start. Finally got it to fire with choke and hot start on and holding throttle open. As soon as I let off hot start and throttle it did instantly. Got it to fire again after kicking for ever and using same procedure as before and same result, fires but won't idle and dies instantly when I let off the throttle.
Any help is appreciated as I am getting very frustrated with the bike. All I need is for it to run good for one last race this year. Thanks again.