Stock Shim Sizes???

Hey guys I was wondering if anyone knows the stock shim sizes for the valves (right intake, center intake, left intake, right exhaust , left exhaust) on a 2006 yz450f. thanks a lot.

They run in the range of 180~190 in most cases, but since each valve is individually set up to the same spec, and each one fits just a little differently, there is no "stock size"; every one is different, and the only way to know is to remove the shim and look.

Your first step should be to check the valve clearance to see if you even need to make any corrections at all. If you do have to adjust, and you're worried that you'll have to wait a long time for the right shim, don't sweat. Honda CRF's use the same 9.48mm diameter shims, and any Honda dealer will have plenty on hand if the Yamaha dealer is out of the size you need.

thanks for the quick response. and yeah i did already check the clearances and they are slightly tight so i wanted to correct it. the main reason i was asking is because i dont want to have to take everything apart just to check the shim size... then put it all back together to go to the dealership to get new shims... then come home and take it all back apart again. i wasnt aware that there wasnt a general stock size so thanks. i guess i was just trying to save time because if i already knew my clearances and knew the 'stock' shim sizes i could just go to the dealership and get the correct shims and only have to take the motor apart once. thank you again.

Why would you put it back together in between? Wasted work. You aren't going to ride the YZ to the dealer.

Be sure that the lifters return to their specific original locations in the head; don't mix them up.

haha i dont know, i guess i am way too obsessed with keeping the engine as free from debris as possible (ie. dust/dirt/lint). but i suppose i could just throw a clean rag on top and be safe. thanks for the input.

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