Motorcycle Repair: Re: Suzuki GS850 answer, e mail address, hi thanx

Question
Hi, thanx for your response to my question re GS850 starting but not revving up. Wasnt sure how to get back in touch so using this again. In answer to your questions all 4 spark plugs are black and sooty and the compression is lower than stated in the Clymer manual as 'service limit' being as follows: 1 = 85psi (6kg/cm2)
                 2 = 85psi (6kg/cm2)
                 3 = 70psi (5kg/cm2)
                 4 = 85psi (6kg/cm2)
Incidentally, the cylinder with the lowest compression has a rather impressive oil leak but not able to see exactly where from! Since checking these the bike will now rev if the throttle is turned very very slowly! I will be cleaning the carbs soon (thanx for the info on this) and if this improves things further will look at what needs doing in the engine. Any further advice much appreciated! Cheers, Jo. E-mail address: red.bike600@tiscali.co.uk

Answer
Jo,

The compression reading are low. Was the engine up to operating temperatures when the tests were performed? If not, did you add a bit of oil to the cylinders to aid with sealing?

The cylinders may need attention before the carbs. Cyllnder compression and valve clearances must be within service limtis before the carburetors will work properly. Once this is in order, we can tune/correct the air-fuel mixtures.

I'll reply further to your email addy.

Mark