how do you do a compression check and where could i get a compression check thingy

 

autozone carries compression testers for as little as 30 bucks. But they arent too accurate, but they will give u an in the ball park reading. The end of it is just like the end of a spark pulg and it threads into yer head. Then u hold the bike full throttle and kick it over until the compression wont go up any higher.


simple
-Nick

 

cool thanks

 

Don't you have to disengage the decompressor?

You'll have to pull the valve cover and pull the de-compressor off the cam to get a true reading.

Make sure you hold your carb open while you are doing the test so you get full air flow into the cylinder. Turn the fuel pet-**** to the "off" position. Don't have to worry about combustion since you don't have spark.

Not sure what pressure you should be looking for. Probably about 150 psig.

You can also do a "leak-down" test with the proper gauge. You pump compressed air into your cylinder with it at TDC (Valves closed) and see how it holds pressure. You shouldn't have more than 3-5% blow-by. My buddy recently did this test because he wasn't getting power and had about 30% blow-by. Turns out he sucked some sand and the jug and rings were a little messed up.