I was wondering if any body knows about what size valve shims to start with on a yfz 450 or where there is a chart on line. I don't feel like buying an entire shim kit yet I rebuilt it bottom up with a 471 stroker crank 12.5/1 piston and I'm going to install stage 3 hot cams a chart would be helpfull but if any one has any ideas that would get me close I would work. Its a 95mm piston. paper work says set clearance to .002 also says some aps. may require more just wondering if any body else has the same set up or what are good size shims to start with. this is realy first time I tore down a gas motor also for break in it says go up 2 main jet sizes does any body know what stock jet size is on an 05 yfz

 

im not sure in the shims but the carb take the bowl off it and on each jet will have a number stamped in it and thats the size then just go 2 up from that

 

problem is I think its already been jetted bigger for the 12.5 that was in it. figure the jetting not to bad more worried about getting an entire shim kit it had no shims under the intakes and it almost looks like flat washers under the exhaust side they arn't stamped or anything. so kind of shooting in the dark. what a basket case but we are learning.

 

ya i dont now what to tell you then iv never done valve alignment and the jetting that just sucks id try to shim it first then see how it running maybe it will be jetted fine not really sure for my 650 three wheeler im going to build for a performance pisten its only 130 so i think im going to go that rout and see how it goes befor i do the big bore build