Loud knocking

[Steve]

Has anyone else had shims break on them?

Although it was not in a Suzuki, the only time I have encountered a broken shim is when I did not get it fully seated before letting the bucket come back up. Cracked it into three pieces. I put them together like a jig-saw puzzle to make sure there were no little pieces that needed to be found before I tried moving the engine to check the next valve. No jagged edges with missing pieces, so I installed a new shim and continued. 8-[

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[81GS550L]

Well now how would a damaged cam lobe factor in all this? Is there any level of accepted damage or does it have to be pristine?

[Dogma]

Well, mine won't be pristine when I put it back together (waiting on parts). This was my first time checking shims, so I didn't have any spares. I tried turning the engine without a shim in it and it chiseled the corners off the lobe and gouged the bucket. This happened at about the same time someone else did a similar thing. The advice we got was to get a flat stone (sharpening stone, talk to your friendly neighborhood machinist) and knock down all the burrs, raised edges, etc. After that, check on it at the next shim inspection (5000 mi). Oh yeah, get a magnet and make sure all the pieces are out, of course.

How bad is yours? I can't imagine what it looks like after running high revs with pieces loose in there. Does the damage show up well if you take a picture?

[81GS550L]

It's definitely not pristine. It's been beat up. I guess I'm at a cross road. Do I tear it all apart and restore or just stay w/what I got 'till it blows up.

[tkent02]

It's definitely not pristine. It's been beat up. I guess I'm at a cross road. Do I tear it all apart and restore or just stay w/what I got 'till it blows up.

Clean the chunks out and run it. It'll be fine, and if not you haven't lost anything by trying.

If the cam is chewed up maybe replace it or at least dress it up, but all it can hurt is the shim.

All the chunks, every particle, might change the oil and filter if you think some might have gotten away.

[81GS550L]

Now that's the reply I like. My sentiments exactly. Cheers! It's no show bike, but everyone who sees it loves it.

[lurch12_2000]

It's definitely not pristine. It's been beat up. I guess I'm at a cross road. Do I tear it all apart and restore or just stay w/what I got 'till it blows up.

I guess I would use a shop vac and clean out any old shim pieces and then look around inside to check again before putting a new shim in.
Your pic doesn't show the lobe so I don't know if anyone here on the forum can really tell if it looks damaged "beyond repair".

[81GS550L]

That was the first pic I took this morning, before I cranked it over. It's beat, but nothing major. I'll take another pic tomorrow, plus I'll keep everyone posted how it is after I put in a new shim and run it. But I do have a question that was still not answered. I noticed the left front shim is cracked, how do I remove it and replace it?

[SabreJim]

Hello,
if you go to this thread and follow the link provided by Matchless....

http://www.thegsresources.com/_forum/showthread.php?t=118133&highlight=shim+tool

bottom line is, use a zip tie(I used a Larger one and bent it a little rather then folding a small one in half) to hold valve open so you can get the chim out with tweezers. The instructions on the link are good. Anyone here will help.

[81GS550L]

A ZIP TIE!? I followed the link, it looks like a great idea. I'm gonna try it. Thank you.

[catbed]

Well, mine won't be pristine when I put it back together (waiting on parts). This was my first time checking shims, so I didn't have any spares. I tried turning the engine without a shim in it and it chiseled the corners off the lobe and gouged the bucket. This happened at about the same time someone else did a similar thing. The advice we got was to get a flat stone (sharpening stone, talk to your friendly neighborhood machinist) and knock down all the burrs, raised edges, etc. After that, check on it at the next shim inspection (5000 mi). Oh yeah, get a magnet and make sure all the pieces are out, of course.

How bad is yours? I can't imagine what it looks like after running high revs with pieces loose in there. Does the damage show up well if you take a picture?

hey thats me! (i think. i suggested using the stone.)

[81GS550L]

[Nessism]

550 cams are dirt cheap on ebay. That cam looks pretty beat, although it would run. I'd just change is seeing as how there is not a lot of money involved.

[81GS550L]

WOW! those GS's in your photobucket are gorgeous. Now that makes me want to totaly restore mine. What is the range in year, and cc, that will fit my '81 550

[Nessism]

WOW! those GS's in your photobucket are gorgeous. Now that makes me want to totaly restore mine. What is the range in year, and cc, that will fit my '81 550

I think any 8V 550 cam will work, just get the right one (intake or exhaust). 1977 - 1982 I think.

Thanks for the comments about my 550's. Rode 400's for years and find the 550 a great size bike for most of the riding I do.

Edit: How about two low mileage cams for $30 shipped? http://cgi.ebay.com/ebaymotors/1982-...3756.m20.l1116