[David C.]

We removed the crankcase cover where the clutch is to see if we could figure out where the knocking was coming from, this is what we found in there; (not the penny of course, that is there for size reference.)

 

["Captain D"]

HMMM...
Welcome to the forum...
Sorry for your loss.
Further teardown required and suggested...

 

[I'mKOHD]

Welcome to the forum. Question when you had it running was it running on both cyls?
The reason for asking is in my opinion for piston rings to get in the crankcase their would have to be major carnage in one cyl. along with some other piston pieces.
The parts in your picture look more like a snap ring or some sort of large spring. A quick look in the parts diagram shows two springs in the clutch assy. although I have no experience with this. As Captain D said "further teardown required and suggested"
Hopefully someone with more knowledge of the clutch system will chime in.

 

[Scared]

Doesnt look like piston rings to me. If those pieces were whole, the diameter looks way too small to be rings. I was thinking snap ring also. Does a magnet stick to them?

 

[vito]

Any chance they are pieces of worn out clutch plates? What year/model bike? Miles? Did you look at the clutch assembly?

I doubt bits that big would make it down into the crankcase without really tearing up the combustion chamber....that would cause noises far beyond some knocking and the pieces don't look all scraped up.

 

[jpr1968]

I'm thinking that they could be pieces of a shim(s). They're too thin for piston rings.

 

[David C.]

HMMM...
Welcome to the forum...
Sorry for your loss.
Further teardown required and suggested...

I was hoping that the problem was a lifter or something easy, maybe top end so that we did not have to remove the entire motor, but at this point, I'm leaning more toward having to remove the motor to see exactly what I have gotten myself into.

 

[David C.]

Welcome to the forum. Question when you had it running was it running on both cyls?
Hopefully someone with more knowledge of the clutch system will chime in.

Yes, it was (is) running on both cylinders. The clutch appears to be fine, in fact everything else on the bike is in excellent condition for it's age.

 

[David C.]

Doesnt look like piston rings to me. If those pieces were whole, the diameter looks way too small to be rings. I was thinking snap ring also. Does a magnet stick to them?

Yes they are magnetic. I fished them out of the crankcase with a magnet.

 

[Scared]

I was hoping that the problem was a lifter or something easy, maybe top end so that we did not have to remove the entire motor, but at this point, I'm leaning more toward having to remove the motor to see exactly what I have gotten myself into.

If the problem came from the top end and made its way to the bottom end, your gonna have a lot more damage. Its better when something comes apart and the pieces stay there. Not travel all the way through the engine.

 

["Captain D"]

That penny sure is dirty

I think I`m leaning towards clutch component pieces...
Maybe a springlike keeper, The notched piece kinda looks familiar and similar to a keeper which resembles a keyring...
BUT there isn`t enough evidence, plus that large square looking piece appears to be from something other than the keeper I have in mind...

A parts fiche for your Bike would be helpful...
What engine???

Welcome

 

[David C.]

Any chance they are pieces of worn out clutch plates? What year/model bike? Miles? Did you look at the clutch assembly?

I doubt bits that big would make it down into the crankcase without really tearing up the combustion chamber....that would cause noises far beyond some knocking and the pieces don't look all scraped up.

It's a 1985 VT500c with 24, 470 miles. (Could be 124,470 miles?)
Could be pieces of clutch plate, the clutch assembly appears to be fine.
I will post a picture.

 

[David C.]

That penny sure is dirty

I think I`m leaning towards clutch component pieces...
Maybe a springlike keeper, The notched piece kinda looks familiar and similar to a keeper which resembles a keyring...
BUT there isn`t enough evidence, plus that large square looking piece appears to be from something other than the keeper I have in mind...

A parts fiche for your Bike would be helpful...
What engine???

Welcome

It's a 1985 VT500C.
Here is a picture of the clutch, it appears to be fine.

 

[David C.]

I'm starting to think that the pieces that I found and the knock are not related.

The knock sounds almost like piston slap, possible worn out piston arm?

 

["Captain D"]

Thinking outloud here...

Yes the clip/ring/fastener I described would hold moving parts in place on a shaft...
And OR act as a spacer between moving parts...
SO = This COULD be associated to the knock???

 

[David C.]

Thinking outloud here...

Yes the clip/ring/fastener I described would hold moving parts in place on a shaft...
And OR act as a spacer between moving parts...
SO = This COULD be associated to the knock???

Everyone here (in my shop) seems to be thinking piston rod, but I can stick my finger in there and it does not have any play, but that doesn't mean anything.

 

[7xclm]

Just a guess, it might be part of the Judder Spring.

 

["Captain D"]

Do any of those pieces fit together so we can have a better look??
I`d be digging out more of it, IF it were me...
My $.02 worth for free

 

[David C.]

Do any of those pieces fit together so we can have a better look??
I`d be digging out more of it, IF it were me...
My $.02 worth for free

I went fishing around in the crankcase and the old oil again, and was only able to find one more piece. The inside diameter is close to 2 inches (Maybe 50mm?) and the thickness is anywhere from .008 to .012 inches (Around .25mm?)

Thanks for all of the help, I really appreciate it. Maybe I can return the favor some day. I own a machine shop (general, not automotive) if you ever need anything.

By the way, none of them seem to fit together fwiw.

 

["Captain D"]

It appears to have spun, with friction scorch marks... MAYBE??

Still a mystery where they go though

But you cleaned your penny