Engine knocking.

[Highway_Glider]

Sometime I hate my bike, other times I love my bike. This is about the former situation.

Hi guys.

It as been a while since I posted last.
Things usually work out. But right now I am out of my league.

The bike: GS1100GK 1983, IDK 140,000 Km or so.

Spent the last 2 months (Not full time but still) working on it.

New rubber, brake pads, valves done, oils changed.
I had to fight an electrical problem but I can see the end of that one. Soon.

Right now I have an engine knock that I can't figure out.

It sounds like this:

My spider sense says its the front side and valve height of the engine. IDK.

Not obvious on the video but if I increase the RPM the knock disappear. I can't ear it any more anyway.

Any thought?

I did redo 3 shims. All the cam clearances / shims are within specs except one that is borderline tight.

After hearing the noise the first time I opened the cam cover and can't see anything obvious.
No screwdrivers or metal chips anyway.

The only thing that comes to mind is a discussion way back when about cams walking.
But I can't remember if there is a noise associated with that. Or what to do about it.

Any help would be appreciated. This is a first for this owner.


Thanks for your read.

[tom203]

My hearing stinks...but since you said this...

"spider sense says its the front side and valve height of the engine. IDK."

camchain hitting something on cover at low revs? Chain slop? Is tensioner ok?
Change that tight shim, recheck others...

[Highway_Glider]

My hearing stinks...but since you said this...

"spider sense says its the front side and valve height of the engine. IDK."

camchain hitting something on cover at low revs? Chain slop? Is tensioner ok?
Change that tight shim, recheck others...

Hi tom203,

Thanks for the reply.

I have checked the chain and the tensioner both seems OK.
Also inspected the cover to see if any gouges appeared. Nothing is amiss visually in there.

Checking the clearance is good and so is changing that one shim for thinner is good practice and I will do that.

But I have changed shims many times before. This doesn't fit.

Other works I have done is to replace the gasket on the L/H cover as well as the starter.
audibly it doesn't seem to come from the side but I will check them too.

[Rust_to_Redemption]

Not obvious on the video but if I increase the RPM the knock disappear. I can't ear it any more anyway.

I'm not as experienced as many others on here with these bikes, but between the sound and the above quote, sounds like the cam walk our GS's are notorious for...

[Gorminrider]

My "cam walk" was much more "regular" in beat but the tone of it was very similar....you could easily find some examples searching this forum or you-tube.
I have a nice mp3 of mine but I haven't been able to trick this site into uploading it.

Perhaps a sticky valve?

[93Bandit]

Sounds like cam walk to me. However like previously mentioned, my 850 is more rhythmic. It goes "knock knock knock... ... ... knock knock knock... ... ..." etc.

[Brendan W]

Another vote for cam walk but as said the 850 is more regular.

[Grimly]

Sounds like slightly more regular than normal cam-walk, but cam-walk all the same.
The absence of it when you rev up just a little pretty much backs it up - they all do it that way.
You're probably worried about why it's started doing it now, if it wasn't doing it before.
The answer to that lies buried with the designer. Many people have tried holding seances to get the answer, but he just won't budge, all you hear is hollow laughter, or possibly cam-walk rattle, distorted by the aether.

[Highway_Glider]

I'm not as experienced as many others on here with these bikes, but between the sound and the above quote, sounds like the cam walk our GS's are notorious for...

My "cam walk" was much more "regular" in beat but the tone of it was very similar....you could easily find some examples searching this forum or you-tube.
I have a nice mp3 of mine but I haven't been able to trick this site into uploading it.

Perhaps a sticky valve?

The sticky valve part occurred to me and I don't want to go there.

Sounds like cam walk to me. However like previously mentioned, my 850 is more rhythmic. It goes "knock knock knock... ... ... knock knock knock... ... ..." etc.

Another vote for cam walk but as said the 850 is more regular.

Sounds like slightly more regular than normal cam-walk, but cam-walk all the same.
The absence of it when you rev up just a little pretty much backs it up - they all do it that way.
You're probably worried about why it's started doing it now, if it wasn't doing it before.
The answer to that lies buried with the designer. Many people have tried holding seances to get the answer, but he just won't budge, all you hear is hollow laughter, or possibly cam-walk rattle, distorted by the aether.

So Cam -Walk it is then.

And yes Grimly I have had the bike for 10 years did 80,000Km (60,000 odd Km at purchase) and it as done many weird thing but not that one ever.

I will learn to live with it.

Thank you all

[Brendan W]

So Cam -Walk it is then.

And yes Grimly I have had the bike for 10 years did 80,000Km (60,000 odd Km at purchase) and it as done many weird thing but not that one ever.

I will learn to live with it.

Thank you all

If you've recently loosened up the valve clearances the cams may now have the space to walk that they didn't have before.

[Highway_Glider]

If you've recently loosened up the valve clearances the cams may now have the space to walk that they didn't have before.

Good point.

But we loosen the clearance every time we replace a shim....

Mind you that at it's venerable age none of the clearances are equal. There is always a few on the tight sides and a few on the loose side.

Maybe it's the first time that I have one of my cam with all it's clearances loose.

[93Bandit]

What is your engine idle set at? I ask because my 850 idled low when I bought it from the PO, about 500 rpms. This made it a little more difficult to keep running when it was cold, but it also made the cam walk more obvious. The general consensus around here is that cam walk is harmless, however it still bothered me a little bit. I bumped the idle up so that it idles just over 1,000 rpms when warm to keep it from dying when cold. An added benefit is that now the cam walk is essentially gone.

Might be something worth trying if listening to it bothers you.

[Highway_Glider]

What is your engine idle set at? I ask because my 850 idled low when I bought it from the PO, about 500 rpms. This made it a little more difficult to keep running when it was cold, but it also made the cam walk more obvious. The general consensus around here is that cam walk is harmless, however it still bothered me a little bit. I bumped the idle up so that it idles just over 1,000 rpms when warm to keep it from dying when cold. An added benefit is that now the cam walk is essentially gone.

Might be something worth trying if listening to it bothers you.

I do not know the idle speed as the cable is broken.

It's about a thousand when warm.

I first notice the noise on my first start of the season after doing a bunch of maintenance.
I think the choke was on that time.

Running it at a higher idle speed is definitively on the table as my voltage is too low at idle.

I have not played with it again as other unrelated issues started to appear.

I have accepted that I I have a cam walker.

Got the bike buttoned up got dressed all happy that I can go riding finally and before I got to the street corner half the indicators had failed.
Back in the barn it went. I thought I had a loom fire on my hands.

I am currently trying to get those sorted to salvage the season.

How the hell does the kickstand switch get bent in the garage over winter?
And the half the bulbs fail at the same time? (Lost left blinker, right running light, neutral, kick stand, instrument lights)
(Voltage spike me think)

Gear indication is gone too. Off to do research for that one.

Thanks all, the forum is the best thing since forever.

[Rich82GS750TZ]

Do you the health status of your battery, RR, and stator?
I think as a first step in diagnosing electrical gremlins you may want to do a quick test (link in my sig)

[Highway_Glider]

Do you the health status of your battery, RR, and stator?
I think as a first step in diagnosing electrical gremlins you may want to do a quick test (link in my sig)

Well I never gave the whole story.

Yes there was a problem that took me a while to sort.
It's OK now (Fingers crossed) but I think the bulbs got weaker for it and my riding to the corner finished them.
Working theory anyway.

Right now the GK is half torn down (Just solved my last indicator problem) I will recheck everything once the fairing and the tank is back on.
I do the test as per BikeCliffs. I will look at your link too.