Last week I got my valves adjusted and 14 miles later a loud clicking noise could be heard coming from the top end of the engine I killed it immediately and had it towed home.  Two of my friends I have talked to say that the guy who adjusted my valves did not correctly secure them afterwards and one has come loose.  The mechanic who worked on my bike says GS's have an issue with the buckets on the exhaust valve getting stuck and that this is what I am hearing, is he just covering his ass and trying not to fix it or could this be true.  The noise is a loud clicking that can be heard at both idle and above and seems to be about half the speed of the RPM's.  If anyone is in the phoenix area, I go to ASU and live in tempe, and can help that would be great.

Kevin O'Brien

To my knowledge adjusting your valves for clearance has nothing to do with securing them other than having the shim seat itself properly in the bucket unless he took the whole cam off to remove a shim in which case you would be better off doing the maintenance yourself. If an exhaust valve were to get stuck in any position you would know it. Either the cam would break or you would have a rough running engine. How many miles are on the bike? I suggest searching for valve noise as I have read about this issue before. Hope this helps.

Quote from: kevinob11 on December 05, 2006, 11:56:17 AM
Last week I got my valves adjusted and 14 miles later a loud clicking noise could be heard coming from the top end of the engine I killed it immediately and had it towed home.  Two of my friends I have talked to say that the guy who adjusted my valves did not correctly secure them afterwards and one has come loose.  The mechanic who worked on my bike says GS's have an issue with the buckets on the exhaust valve getting stuck and that this is what I am hearing, is he just covering his ass and trying not to fix it or could this be true.  The noise is a loud clicking that can be heard at both idle and above and seems to be about half the speed of the RPM's.  If anyone is in the phoenix area, I go to ASU and live in tempe, and can help that would be great.

Kevin O'Brien

Pop open your valve cover and look around. I would also turn the engine by hand and observe it. Do this by poping of the generator cover on the right side of the bike the try rotating the engine with a 19mm (is it 19?) wrench

Here is the video of how to remove your valve cover and do a valve inspectiong 

http://tussey.dreamhosters.com/movies/Cars%20and%20Bikes/GS500ValveAdjustment.wmv

It is a 19mm.

The exhaust buckets (not shims) do get a little tight from heat expansion, ususally due to lean (read: hot) running conditions and carburetion (this is where the lean part comes in).  But, it is not common.  My left one has scoring, and is difficult to spin or move as it is so tight.

Did your two freinds open up your bike and look into it, and confirm that is what happened?

I'll throw in another thing to suspect and that is that oil had gotten under the shim and the mechanic needlessly swapped out the shim for a thinner one, and now you've got that ticking.

Or, it's the knocking from camshaft end-play.

Or, you ran low on oil, and there isn't enough getting to the head to lubricate (and "cushion") the cams (or camlobe/shim interface).

But, I digress...I'm just conjecturing.

Quote from: scratch on December 05, 2006, 03:36:42 PMDid your two freinds open up your bike and look into it, and confirm that is what happened?

Prolly not, because they state a possible problem for screw-adjustable valves, which the GS does not have.

Quote from: kevinob11 on December 05, 2006, 11:56:17 AM
Last week I got my valves adjusted and 14 miles later a loud clicking noise could be heard coming from the top end of the engine I killed it immediately and had it towed home.  Two of my friends I have talked to say that the guy who adjusted my valves did not correctly secure them afterwards and one has come loose.  The mechanic who worked on my bike says GS's have an issue with the buckets on the exhaust valve getting stuck and that this is what I am hearing, is he just covering his ass and trying not to fix it or could this be true.  The noise is a loud clicking that can be heard at both idle and above and seems to be about half the speed of the RPM's.  If anyone is in the phoenix area, I go to ASU and live in tempe, and can help that would be great.

Kevin O'Brien

From what you described...the valve clearances were not set correctly. They are gapped too big.

To my knowledge, there has been only 1 person (GSJack) that has posted about a sticking bucket. It is far from common.

Quote from: dgyver on December 06, 2006, 10:26:14 AM

Quote from: kevinob11 on December 05, 2006, 11:56:17 AM
Last week I got my valves adjusted and 14 miles later a loud clicking noise could be heard coming from the top end of the engine I killed it immediately and had it towed home.  Two of my friends I have talked to say that the guy who adjusted my valves did not correctly secure them afterwards and one has come loose.  The mechanic who worked on my bike says GS's have an issue with the buckets on the exhaust valve getting stuck and that this is what I am hearing, is he just covering his ass and trying not to fix it or could this be true.  The noise is a loud clicking that can be heard at both idle and above and seems to be about half the speed of the RPM's.  If anyone is in the phoenix area, I go to ASU and live in tempe, and can help that would be great.

Kevin O'Brien

From what you described...the valve clearances were not set correctly. They are gapped too big.

To my knowledge, there has been only 1 person (GSJack) that has posted about a sticking bucket. It is far from common.

Quote from: scratch on December 05, 2006, 03:36:42 PMThe exhaust buckets (not shims) do get a little tight from heat expansion, ususally due to lean (read: hot) running conditions and carburetion (this is where the lean part comes in).  But, it is not common.  My left one has scoring, and is difficult to spin or move as it is so tight.

We are talking about steel buckets in an aluminum head and aluminum expands at a greater rate than steel when heated.  When the engine heats up the buckets become looser and valve clearances become greater.  So in this case the bucket didn't become tighter and stick after 14 miles but the valve clearances could have become looser and gotten noisy after 14 miles like dryver suggests.  Need to pull the valve cover and see what's going on here.

I checked this out for myself years ago on a CB750K which had screw adjusted valves to see how much looser the valve clearances were when hot.  The settings were around .004-.006" cold and when I checked them hot they had .015-.020" clearance  and must have cooled a bit already while I was getting the tank and valve cover off.

I have yet to hear of any other cases of tight buckets like I had causing a GS engine crash, but there could have been many other slightly tight buckets that went undetected.  I bought the 02 GS used in Sept 03 with about 4k miles on it and the engine didn't crash till Mar 05 with 21k miles on the bike.  I had detected the tight bucket on the first valve check and after that noticed the engine was a bit rough for maybe 30 sec or so after start up and could feel it smooth out and the slight clicking noise go away as warming of the head freed the bucket.  Decided to let it go till the valve in question needed a shim changed.

It was a cold morning about 30F as I recall and I just cranked it a turn or two with the starter and the tight bucket stuck the valve open and the engine stopped with a bang.  The head of an exhaust valve was snapped off and locked it up.  I repaired the engine and now have over 44k miles on it without further trouble and will never let a tight bucket go again.   

I watched Kerry's video and now have a little better idea about how everything should look and operate on a GS.  This is my first one.  The two intake valves are both at about .06 mm.  The gap on the exhaust valves were .11 mm and .17 mm.  If I am correct the right size is .080 at the most, could this much of a difference cause this loud of a clicking noise?  Also if he screwed up on the shim size because of oil under the shim why would it have taken 14 miles for this noise to be heard?  Thanks for all the posts everyone.  Everything else under the valve cover seems to be operating properly, none of the buckets have been sticking as far as i can see and I pulled the exhaust system and watched the valves operate as i turned the crank and everything seems to be operating smoothly there as well.  Is the GS a single or dual valve spring?

It does not take much extra clearance to have the loud ticking noise.

It is a dual spring.