Bandit Alley

MODEL SPECIFIC => SUZUKI BANDIT 250 & 400 => Topic started by: CrustyOreo on April 05, 2014, 08:09:00 PM

Title: Compression Test
Post by: CrustyOreo on April 05, 2014, 08:09:00 PM

I picked up a Bandit with a "seized motor"
But I can crank it over  :duh: I'd like to do a compression test but my repair manual says to do a compression test only when fully warmed up  :stickpoke:
The carbs are old and dirty so I'd rather not go through all the effort of trying to get this motor running (if it will at all) before doing a compression test.

Is it safe to do a compression test with the motor cold? If so, what numbers should I be looking for? Repair manual says a warm motor should be over 114.

Title: Re: Compression Test
Post by: ventYl on April 06, 2014, 04:49:05 AM

It is safe to do compression test on cold engine. Don't rely on accurate value, just compare difference between cylinders and do two sets of test. First do it "dry" and then do another test with some oil in cylinder. If values with oil in cylinder will be dramatically different, then your piston rings are done. Anything with cold compression above 6 bar should be crankable but with lowered power output.

Title: Re: Compression Test
Post by: shidoran on April 13, 2014, 06:23:36 PM

I've done one on mine cold. There's a good link here that will talk you through it:

http://www.2fiftycc.com/index.php?threads/howto-compression-testing-a-motorcycle.2087/