cold valve clatter

[blynn]

All,

I am still workig on this clatter sound I hear comming from my 81 GS650G. It does seem to go away once the engine is hot. Lets say the tappet shims are too warn (too much gap) by just a very tiney bit. Will they swell and close the gap enough when the engine gets hot? Maybe this is why the clatter goes away after about the first 15 minutes of riding. Anyone have a similar experience? thnaks.


R/ Bill

[focus frenzy]

hard to say without actualy hearing the sound and pin point where it is comming from.

what you can do is get a tube (short piece of garden hose, conduit, etc,,) and fire up the bike and put tube to a ear and slowly work it over the engine till the clatter is the loudest.
you will need to get the tube close to the engine and go from one end to the other to narrow down where the noise is from.

it could be as simple as cam end float (common and normal with the GS) or slightly loose clearances on the valves.
it could also be cam chain slap or rod or piston knock.

[flyingace]

Somewhere in the bowels of GSresources is a page describing clatter from the camshaft ends (or something like that). I found it while trying to diagnose a noise of my own. It sounded similar to your problem since it went away once warm. The good news was that it was harmless, the bad that there wasn't much you could do apart from machining.

You may want to do a search on 'valve clatter' or 'camshaft noise', etc.

[tconroy]

All,

I am still workig on this clatter sound I hear comming from my 81 GS650G. It does seem to go away once the engine is hot. Lets say the tappet shims are too warn (too much gap) by just a very tiney bit. Will they swell and close the gap enough when the engine gets hot? Maybe this is why the clatter goes away after about the first 15 minutes of riding. Anyone have a similar experience? thnaks.


R/ Bill

my 83 650 gl is alittle noisey at idle also but it doesnt effect the performance at all.I think mine is mostly cam endplay. i also need to sync my carbs.i heard that it may quiet it down some.Sometime clutches rattle too.mine doesnt rattle at all when I let out on the clutch and start going,it seems to be just at idle.Ive heard these engines are noisy anyway so i just ignore it.

[bwringer]

Stoplights during GS rallies are pretty noisy places. They're noisy bikes, and they all sound a little different. Clattering and tapping noises are often harmless.

On the other hand, some noises are worth paying attention to, like squaeling or grinding. If you've checked everything, then don't worry about it.

[rustybronco]

I bought my gs in august of last year, when i first got her thought it was comeing apart what with all the tapping, ticking and slapping going on and i'm saying to myself what did i just buy? i was so sure that i had excessive valve clearance or piston slap because i could hear this one valve tapping when ever i opened the throttle with the engine under load, i took it apart last week to adjust the valves and three valves were at .04mm -.05mm the others were between .00mm and .02mm! i adjusted the valves so all were between .04mm and .07mm, put it back together fired her up rode it 10 miles and NOT A SOUND! go figure! goofy engine at best and i have had three other bikes.
My point is they are just full of sounds and if it wasn't noisy i'd worry, it will drive you nuts trying to figure it out (as long as its not to loud) , after 2,500 miles I've come know that it is just part of her soul.