Q: I’ve recently got my wife/girlfriend/spouse or whatever into motorcycling after 30-years of being together, we’ve now both just turned 60 and loving life more by the day. So don’t worry about getting old, life still goes on the way you want it to.
Anyway, I didn’t want to buy her a modern bike because I don’t understand them and I ride a 1980 Honda Goldwing anyway. So I found her a late seventies Suzuki GS550 E, which is in fairly good condition and has 73.000km on the speedo.
When we got it home we realized that it doesn’t run, as it should. So I set the points and fitted new plugs and air filter because I know how to do that and flushed the carbs through which improved things a little, but we still weren’t happy.
So a friend of mine came over with a compression tester and it revealed that two of the cylinders (1 and 3) was low compared to the others. The bike doesn’t smoke while it’s running so we think it could be the valves and not a piston problem. So my question is, do think it’s the valves also and will it be a problem to fix them – have to get the wife on the road ASAP?
Arnold Cummings.
A: It sounds like you’ve eliminated most things already and these older bikes are relatively easy to work on so that’s not a problem here. So I would certainly now check out the valve clearances because that can easily cause a compression drop, and maybe they haven’t been checked after many years of use.
You’ll have to take off the cam cover and I’d make sure you’ve a new gasket for this first, which a Suzuki dealer or aftermarket parts dealer will be able to get for you. Once inside turn the crank over and check the gap for each of the eight valves with a feeler gauge and set them between four to six thou’, some people set them four on the inlet and six on the exhaust. If they’re too tight, which I expect they are, you’ll have to change the shim size accordingly, so it might be best to take it to a Suzuki dealer who has the different sized shims in stock, otherwise you won’t be able to complete the job.
Then once all the valve clearances are correct and within specification check the compressions again, and again after you’ve ridden it for a few hundred kilometers to let the valves ‘seat’ again, I then believe things inside your motor should be much better. Hope your wife/spouse/girlfriend enjoys her new ride?
