Knocking?

[LWright]

My 83 XL600R has a knocking sound at idle. Maybe I am in denial but I do not think it is piston or rod. I just installed a used piston and cylinder and those parts seemed to fit well. I can rock the crankshaft back and forth without creating any sounds. What I do get is a knock when the timing chain tensioner "jumps" to take up slack. I can see this with the valve adjusting caps off.

My question, can a worn timing chain cause a knocking sound?

Thanks

[Horri]

Things such as Pistons/Gudgeons/Crank rods should not "seem to fit well" they should all be mic'd and tested by a bloke who knows how to read the manual and measure tolerances..I get an engineer to sort that stuff out as I'm not really precise enough when using the tools required plus I don't have what I regard as the knowledge or tools accurate enough for the job..

Re the CamChain..I don't know how you could see the Tensioner mechanism working by looking through the inspection covers but it may very well be faulty or worn out as may be the chain and guides. Best thing to do is replace the lot..No way to tell which may be the issue nor whether replacing them will fix this "knock"..I know what a big end knock sounds like,,it stays the same and gets louder with revving but other knocks ,,who knows..

[pwrpapa]

Usualy the timing chain will make a rattle noise when loose.

Is it possible that you did not install the timing chain adjuster properly or it's worn out.

It should only move in the tight position not back and forth.

It's a ratchet devise and only gets tighter not looser.

Did you remember to install the tensioner bolt?

Pop's

[LWright]

Usualy the timing chain will make a rattle noise when loose.

Is it possible that you did not install the timing chain adjuster properly or it's worn out.

It should only move in the tight position not back and forth.

It's a ratchet devise and only gets tighter not looser.

Did you remember to install the tensioner bolt?

Pop's

Thank you. This is useful information that makes sense, it does not seem right that the chain would be going slack. Time to take it back out and see what I might have done wrong. I did install the tensioner pin, sure was a pain getting that spring into place. Might hit up the local shop to borrow the tool or any suggestions other than zip ties?

BTW I ordered a factory service manual to replace the Clymer, maybe that will help!

[LWright]

Another question.

"It's a ratchet devise and only gets tighter not looser."

My impression of the tensioner "lifting device" was that it is a simple spring loaded lever. I admit I did not look all that closely at it and that might have been why I had so much trouble with the spring, failing to release the ratchet.

I will pay more attention when I tear it down again but any insights would be helpful.

thanks

ps. It is always possible that I screwed up through ignorance, plain stupidity, or high or low blood sugar levels.

[pwrpapa]

The only reason for the spring is to tighten and take the slack out of the chain,then the tensioner comes into play and keeps the chain tight sorta like a one way clutch.

If the chain were able to flutter which it would if it only were keep tight by a spring, it would throw your cam timing off and your bike would run like poo.

No different than the chain on your rear wheel bouncing up and down when you get on the throttle.

Pop's

[LWright]

So it is the interface between the "Lifter" and the "Tensioner/guide" that creates the ratcheting effect?

[LWright]

Went back in for another look, found a broken timing chain guide, the one opposite the tensioner. I also confirmed that the tensioner itself is not locking as it should. Easy to see the one-way clutch now that I know to look for it, thank you Pops.

[Horri]

Lucky you found that..My 86 snapped one of the little tabs off one of the guides,,thankfully It must have happened as I was kicking it over..Chain kinked and locked the entire thing up. Lucky it wasn't actually running or the damage would have been substantial..Bet the one that let go is the same as mine..Must be an age thing..

[LWright]

I picked up another tensioner and played with it today. Went in easy after I pulled the spring out of the lifter body, set the chain and bolted the gear on the cam, then pulled the spring back into place. First time around I tried to compress the spring to install the lifter.

As long as I learn from my mistakes, all should work out.