WR450 w' YZ Cams, Starter Struggles

Just put Yz cams in my 05 wr450. Runs out up top great now but... starter sure has a hard time if motor is coming up on compression. Have to kick it through a little to open a valve so it will start off the button. Nature of the yz valve events??

http://www.thumpertalk.com/forum/showthread.php?t=401894&highlight=yz+starting

Ok I found this thread. I'm thinking my camchain might be a tad tight. I just let the spring pop back by itself to do the tensioning but maybe it went a click to far. Bike is a little harder to kick also. Not compression wise, but motor feels like it's in a little bit of a bind when trying to kick.

Mate, I just put a YZ cam in an '03wr450 and spent a lot of time getting the valve clearances just right:crazy: and also put in a 40 leak jet,cranks and starts fine.we in AUS have good fuel so i try and use 98 or 95 octane,we have 100 octane but i haven't used it the wr yet.I think we have to jet a tad leaner than you do.Using 48p,168main, jd red 4th clip.1.5 turns.The timing chain cant be too tight ,the tensioner is self adjusting and anyway the timing is ether right or wrong,chain tension wont change it.

Cam timing is not the problem, I know how to time an engine. I'll play with it and see what happens.

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