decompression on a 05 crf 450r

What should I look for on my crf its hard to kick over but when it starts it runs great just before it does ill kick it over from a stand where I can put all my weight in it, out on the track if I go down it's push it back to the tricks

the little spring may have come off the decompression weight. it's on the far right side of the cam shaft. The weight should spring back. removeing hte valve cover sometimes, you inadvertently pull the spring off the decomp weight.

I will check tomorrow I hope this is it im tired of this hard starting

O how many weights are there

O how many weights are there

just one. it's about 1" long or less, it's ont eh end of the cam. you can't miss it. just use your finger to move it outward (the position that it's in as soon as the motor begins to fire up, more than 600rpm). It should snap back in..

inspect the valve clearances first. Also the decompression clearance

inspect the valve clearances first. Also the decompression clearance

if the clearances were tight or zeroed out, you would be able to kick it over easy.. he can't kick it over at all, even standing on the kick starter. may as well check stuff while in there, but i have pulled the spring off before when removing the valve cover on this style decomp mechanism. it gets caught on the rubber cover gasket if you aren't careful.

Edited by MELK-MAN


if the valves are zero'd out he may be hitting the piston with the valve causing lockup. A cam out of time would amplify this issue

Edited by JJRace

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