Yamaha 2004 WR 450

[wr450senior]

Hey is there anything special about doing a compression check on my 04 WR 450? All I know is to warm the engine up install the compression tester and hold the throttle wide open while spinning the engine for 3 or 4 seconds. Am I missing anything here? Thanks for your help.

[mcflzwr450f]

I think you want the reading from the 3rd compression stroke, someone correct me if I'm wrong.

[txaggie929]

That's about right, the third or fourth. You don't have to hold the throttle wide open, but you can. Check it both ways for grins.