Noisy valve train or...?

[Bruin]

I am pretty sure it is time to check my valve clearances. My 650 is making two strange noises. You know the sound a cordless drill makes when it hits the torque setting you picked for it? Under acceleration it sounds like four cordless drills under my gas tank. I guess the best description of the noise would be a "clacking" sound. The second noise happens if I let off the throttle completely after a hard acceleration, it sounds like someone jingling a set of keys. For any of you who were ever in the military, it sounds exactly like the noise your dog tags make when you run, only really fast. There is no noise at a steady cruising speed or very light acceleration. It also pukes blue smoke for the first two minutes or so of a cold start. This leads me to believe that new valve seals are in order. I don't have a lot of tools at my house so I think I will take a case of beer to my uncle's house in exchange for the use of his tools, garage, and motorcycle knowledge. His knowledge is mostly about Harleys so I am looking for some advice from some of you Suzuki gurus before I go to his place. What do you guys think? Bike is an 81 GS 650GL with about 23,000 miles.

[Dave_17954]

i was leaning towrds either cam chain tensioner not adjusted right or clutch rattle. mine had that sound once last summer ( the drill sound you mentioned) and my cam chain tensioner was adjusted wrong but I've never had the jingle sound.

[49er]

I am pretty sure it is time to check my valve clearances. My 650 is making two strange noises. You know the sound a cordless drill makes when it hits the torque setting you picked for it? Under acceleration it sounds like four cordless drills under my gas tank. I guess the best description of the noise would be a "clacking" sound. The second noise happens if I let off the throttle completely after a hard acceleration, it sounds like someone jingling a set of keys. For any of you who were ever in the military, it sounds exactly like the noise your dog tags make when you run, only really fast. There is no noise at a steady cruising speed or very light acceleration. It also pukes blue smoke for the first two minutes or so of a cold start. This leads me to believe that new valve seals are in order. I don't have a lot of tools at my house so I think I will take a case of beer to my uncle's house in exchange for the use of his tools, garage, and motorcycle knowledge. His knowledge is mostly about Harleys so I am looking for some advice from some of you Suzuki gurus before I go to his place. What do you guys think? Bike is an 81 GS 650GL with about 23,000 miles.

I doubt that it's your valve train, as the noise should still be there at moderate loads too.

Without hearing it, sounds a bit like a big end bearing. You would also hear detonation under load, but you wouldn't hear it under decel as well, so we can rule that out too.

Your engine has shell bearings which are more prone to failure than the roller bearing models.
When you start it again, place the end of a screw driver shaft against the bottom of the crankcase. By placing your ear against the handle you can now use it as a stethoscope. Blip the throttle moving the screw driver from cylnder to cylinder until you can identify which bearing has failed. If it's a bearing failure, you will hear quite a knock, which will increase in intensity with rpm increases. The knock is really accentuated when the engine is under load, as in hard acceleration.

This is the worst case scenario. Engine noises are hard to diagnose without actually hearing them. Good luck.

[Bruin]

The noise doesn't get louder with increased RPMs, it's just there every time I accelerate. I have been screwing around with the clutch adjustment and have heard that a poorly adjusted clutch will cause strange noises too.

[SAN]

eng noise

I agree with 49R, Eng noise is hard to diagnose, even when standing on bike! So not to scare you, could be what 49R sugg. Or if you think its top end I've read these early 650's having oil flow probs to cam's, under load end play at cams might make your noise. or could be your clutch playing. SAN

[MrZig]

The noise doesn't get louder with increased RPMs, it's just there every time I accelerate. I have been screwing around with the clutch adjustment and have heard that a poorly adjusted clutch will cause strange noises too.

Oh god, this is the sound my GSX400 engine made before it seized on me. Check your oil level and pressure if possible. hopefully it's not the same death tick.

[Don-lo]

It is almost definitely your cam chain tensioner. Pull it, clean it and reset it correctly. There are previous threads detailing it.