When doing a Compression Test?

[Turbobanshee_kid]

Do i just screw the thing down into were the spark plug goes and kick it tell the psi does not go up anymore? then do it for the other side? Do i need to do some thing as?

 

Does the side I'm not doing spark plug and coil end need to be on and it the head? when doing the test?

 

killswitch need to be on?

[Handyman]

what doing a compression test you want to screw in the tester all the way. On the side you are not testing pull the plug boot off and make sure it won't touch the spark plug(for safety that it won't start) you can turn on the ignition if you want. When doing the test kick the engine over until the needle stops climbing and read your psi. do the same for the other side.

[Fastdadtsmith]

***Important, make sure you have the throttle wide open when kicking. I don't know why, but last month I was going thru the same process and was told to keep throttle open. :beer:

[jbooker82]

***Important, make sure you have the throttle wide open when kicking. I don't know why, but last month I was going thru the same process and was told to keep throttle open. :beer:

 

That way the engine can pull air in. If you have it closed then your not going to get a full compression reading becuase there is a lack of air.

[Turbobanshee_kid]

should both spark plugs be out?

[Handyman]

should both spark plugs be out?

 

yup

[hittintrees srh]

yup

 

why??? ive always been told/and ever done only one side at a time.

 

also warm your motor for a bit-that way your test dictates what your comp. # is while ridding.

[Barrymaxx]

Ok, first start your motor and let it get up to operating temeprature. This will get you up to the compression you have when the piston is expanded and everythings hot. Then pull one plug and screw the tester in. Turn killswitch off, give it full throttle, and kick untill it levels of. Then take it out and put the plug back in, then repeat for the other side.

 

I prefer to leave the other plug in so nothing gets sucked in or falls in. Its only a little harder to kick.

[PassionRE]

Ok, first start your motor and let it get up to operating temeprature. This will get you up to the compression you have when the piston is expanded and everythings hot. Then pull one plug and screw the tester in. Turn killswitch off, give it full throttle, and kick untill it levels of. Then take it out and put the plug back in, then repeat for the other side.

 

I prefer to leave the other plug in so nothing gets sucked in or falls in. Its only a little harder to kick.

Warm motor, both plugs out and spark plug leads grounded, full throttle ...kick until pressure reading stops rising...Jim

[Satsol67]

I would also do it while its cold. If your having problems starting it when its cold could be your rings arent seating right. When you do it when its warm the rings would have expanded giving you more compression. Now if it fires right up on 1 or 2 kicks then really no need to do it while its cold. Just my opinion.

[Handyman]

I would also do it while its cold. If your having problems starting it when its cold could be your rings arent seating right. When you do it when its warm the rings would have expanded giving you more compression. Now if it fires right up on 1 or 2 kicks then really no need to do it while its cold. Just my opinion.

 

When I first bought my 99 it would start on the first couple kicks. I did a comp test due to some other issues and found that when cold the compression was about 110 on both sides. After I warmed it up the compression would drop to below 80. That's how I found a needed to do my top end, otherwise I would have never known. Bike ran a hell of alot better afterwards