99 wr400, bought a set of Yz450 cams, need some help installing them

[unzy87]

     

Hey so bought some 03 yz450 cams, intake and exhaust for my 99 wr400, foot couldn't handle kicking it anymore. Does anyone have any info as to what timing I should be using to set this up? I've seen lots of different ideas but I'm looking for the best timing setup. Any info or current setups like this would be a bunch of help. Thanks guys

[PawPaw]

Set them to factory marks, but first be sure they will fit. Somewhere in that era they changed the cam gears to a different gear tooth size that may not match your crank gear. They will look the same, but if different they will cause the cam chain to wear fast and thus wear the crank quickly as well.

Paw Paw

[cowboyona426]

Look for my post on the YZ450 cam mod, I think it's in the knowledge base. The photos are long gone but the process is explained in detail. With the piston at TDC you want the cam lobes facing opposite each other, and I think 14 cam chain pins between the timing dots on the 2 cams.