Lower-end noise from my GS850 daily driver

[Roostabunny]

Dang.

It's all back together and still made the same noise. Maybe a smidge better, but definitely still there.

Even with this diagram it's hard to see for sure the difference between what I'm calling "rotational" movement and what I'm calling "side-to-side" movement. But I'll give it another go just to make sure.

Essentially, the basket can pivot around its center about 1/4-1/2" (measured along outside edge of the basket) in either direction relative to the big gear.

It doesn't spring back into place - it just stays wherever in that arc I pivot it.

 

[blowerbike]

that is not your noise....but, i like you drawings:evil:

 

[rustybronco]

I just checked the clutch basket I have lying around. You can move the aluminum clutch basket in relation to the gear when a bit of force is applied. The basket will move and stay in that position until force is applied in the other direction. The dampening springs in my spare basket are a little loose. I'd say it moved it 3/16" of inch.

Note, I do not mean rotating the clutch hub (the piece I sent you) in relation to the aluminum clutch basket.

Clutch basket... https://lh3.googleusercontent.com/-...AAAK78/1H6jnljuWRg/w1024-h724-no/P1110814.JPG

 

[Roostabunny]

that is not your noise....but, i like you drawings:evil:

Lol, thanks.

It's been suggested to tackle the carb sync next and see if that helps.

I'll feel a little silly if that fixes it, though there's no doubting that clutch hub nut was very loose and the hub was taking damage, so it wasn't a waste of time.

 

[Roostabunny]

I just checked the clutch basket I have lying around. You can move the aluminum clutch basket in relation to the gear when a bit of force is applied. The basket will move and stay in that position until force is applied in the other direction. The dampening springs in my spare basket are a little loose. I'd say it moved it 3/16" of inch.

Note, I do not mean rotating the clutch hub (the piece I sent you) in relation to the aluminum clutch basket.

OK, thanks for checking that out. I'll check that carb sync and see what impact that has - was on my to-do list anyway since discovering and fixing that intake leak at the airbox boots.

Edit: Not complaining, but so wishing for a garage right now. This is the most challenging bike problem I've had in years, and I wish I wasn't so limited on when I could work. Reassembled today and had to put on the headlamp to finish.

 

[Roostabunny]

Well, I synced the carbs (they were not that far off in the first place) and that didn't effect the noise.

I wish I had a better way to get audio of the noise - the videos I take totally skew the sound to the higher frequencies so that the tapping is almost all you hear - makes the noise sound much worse than it sounds in person.

That said, it's certainly still there.

Honestly, I'm feeling extra pressure because I don't have a back-up vehicle and I feel as though I've kinda worn out my welcome on the ride I've been borrowing for the last three weeks. I'm working on that as well - but I'm finding strangely unmotivated sellers.

So, anyway... I'm open to other ideas of things to look at. Since getting the clutch tightened up I'm now wondering if the remaining noise might be originating from the top end, but I'm not sure how to narrow that down or if it's possible to narrow it down.

 

[exdirtbiker]

I gave this whole thing a quick read... Sorry if I missed something...
but I'm not convinced you have eliminated the "loose springs in basket" as a possible cause... [click on the pics to watch video ]

at about 5-6 seconds in, I'm blipping the throttle...

That noise was caused by this:

 

[blowerbike]

anything is possible but 850 baskets never get as loose as 1000/1100/1150 springs.
if he had a loner 850 basket to try that would tell the tale.

i have started engines with the clutch side empty to see if noises went away.
running the engine for a few seconds will hurt nothing.
just a thought....

 

[Roostabunny]

I gave this whole thing a quick read... Sorry if I missed something...
but I'm not convinced you have eliminated the "loose springs in basket" as a possible cause...

Interesting. Mine had a slight rattle when removed - not quite the metal maraca you've got there, but you never know.

Mr. Blowerbike - so get it back this point

... and then crank it up?

I'm thinking the short duration is mainly because there's nothing driving the oil pump? And do I need to actually drain the oil again to do this test without causing an ecological incident, or am I ok on the side stand?

I think this will be my best bet - at least if I still hear that sound I'll know for sure it's not the clutch.

 

[blowerbike]

yes as pictured..no basket pump gear...all the way back to the trans bearing.
install clutch cover and fire it up.
you should know if the noise is gone within a few seconds...no more second guessing.
if this is not the area then you can button up the clutch side and move on.

 

[CSaddict]

Im very curious on the out come of this. Mine makes a knock at idle as well but disappears at higher rpm and has plenty of power. Mine sounds like its coming from the trans.

 

[megatwin]

Just curious,when you had the rotor off,did you try lifting the end of the crankshaft to see if you could detect any movement?
Same with the trans input shaft?

 

[Roostabunny]

Sorry to report that this issue has been on hold this whole time. Nothing done.

I bought a cage for the first time in 7 years, because I had worn out my welcome on loaner DD's. Course I bought my long-time dream car, a 1991 Toyota Land Cruiser. Needless to say, now both my dd and my backup are projects, and life's been throwing too many curve balls to keep the Toyota running and get the GS back on the road.

But aside from the nice weather, the gas bill on Toyota (and I knew about that before I bought it) means I'm pretty anxious to get back to work and back riding. Travel plans and such means it may be another 2-3 weeks before there's an update, but next step is still pull the clutch, replace the cover, and run it for a few seconds to see if the noise goes away.

Actually, the next step is "get her started", which is my fault. Seven years of riding all winter, I never thought she'd ever ever sit this long!

 

[londonboards]

I'm sure you know this by now but I couldn't find a post on here that describes it.

In one of your photos and the hand drawn diagram above, you show movement between the outer clutch basket and the gear that is attached to it. This is what those springs are on the back of the clutch basket. They are supposed to cushion the power being transferred from crank to clutch. The crank gear will turn the clutch basket gear which will turn the clutch basket after the 1/4 - 1/2 inch slack has been absorbed by those springs. Those springs, particularly the fat ones, get compressed over time and consequently rattle in their sockets. The only way to fix this is to grind off the big rivets and put in new springs and weld the basket up again.

The big question is; does the rattling of these springs cause the noise problem that you have? You can test this by running the engine, taking off the oil filler cap, engaging first gear and just lightly letting out the clutch and holding it just where it bites. This should take the slack out of the clutch basket springs and if that is the cause of the rattle, the noise should diminish.

I have 2 GS1100Gs and both clutches are out at the moment. See my posting on clutch rattle here:

http://www.thegsresources.com/_forum/showthread.php?p=1989964#poststop

I have been battling this problem for ages.

My current view (my view changes as I eliminate reasons for the rattle) is that there is (as you have shown) some movement of the complete clutch along the drive shaft. I have read somewhere on here, that this movement can be because the spacer that the clutch basket sits on is fractionally wider than the clutch basket itself. So no matter how hard you tighten the clutch hub nut, whole thing will still move. If this was the case, then it would stand to reason, that one of the tests you see being applied to this noise, namely running the bike and pulling the clutch in to see if the noise goes away, will not work. In my case the noise does not go away when you do this but it changes pitch somewhat. This leads me to believe that this movement is the result of lateral play of the basket on the shaft. When the clutch is pulled in it simply allows a little more movement and therefore a different tone to the noise. However when the engine is revved up, for me at least, much of the noise goes away. Somehow I have convinced myself that this would happen if it was lateral movement. I assume at higher and smoother revolutions this lateral play would not occur or at least not rattle.

I do believe someone on here even had their spacer ground down somewhat to eliminate this problem and all their noise issues went away. I have also been told that if this component was ground down, it's strength would be compromised and this should therefore not be attempted.

At the end of the day, with tons of advice from very learned mechanics and engineers, I have reached the conclusion that the noise is not conveying any message of impending doom and it is best ignored. Don't take the oil filler cap off and you won't hear it. Rev the bike up and it's gone. I am going to try this approach for this summer at least!

Good luck with yours.

Greetings

 

[exdirtbiker]

I have reached the conclusion that the noise is not conveying any message of impending doom and it is best ignored.

:clap::clap::clap:

But... if we all did that, this forum would dry up and die in a week !!! :-\\\

 

[Roostabunny]

:clap::clap::clap:

But... if we all did that, this forum would dry up and die in a week !!! :-\\\

Ha! Well said.

 

[Roostabunny]

The big question is; does the rattling of these springs cause the noise problem that you have? You can test this by running the engine, taking off the oil filler cap, engaging first gear and just lightly letting out the clutch and holding it just where it bites. This should take the slack out of the clutch basket springs and if that is the cause of the rattle, the noise should diminish.

I'm going to check this out. I'm actually still kind of hoping it's clutch rattle, but couldn't prove it to my own satisfaction. Your thread was terrific, and the youtube vid was the best comparison I've had access to. It's been so long since I've heard the sound on mine though...

Just never thought to try popping out the oil fill cap to listen.

Questions for you - did you feel that vibration all the way up through the bars? No reason you shouldn't, I guess, but I'm curious about your experience.

And you mentioned letting the clutch out till it just bites to test the noise - do you feel/hear the rattle at cruising speed with the clutch lever fully released?

 

[londonboards]

Roostabunny - no I do not feel any more vibration than I have experienced riding any of these bikes over 30 years. I always feel a bad vibe patch somewhere around 3,750 to 4,250 revs but it is never intrusive. No it seems to me that all this clutch noise simply goes away when the bike is ridden or revved highly which comforts me when I am cruising at 80 mph on the highway. Obviously difficult to hear anything at speed.

If you are still not clear where this noise is coming from you can narrow down the area by using a doctors stethoscope device to listen to different parts of the motor when it is spinning. Or you can do what I do. Take a 2 foot piece of 1" x 2" timber. Put one end firmly on any part of the engine whilst it is running and put the other end firmly on the ear bone (or on the little flap in the centre of the ear). You will hear every single thing. Listen to other motors to compare sounds. You can eliminate cam chain thrash, cam shaft bearing problems and a host of other potential noise producing problems like this.

And never underestimate the potential of a good carb sync to eliminate a lot of engine rattle. Just having one cylinder slightly out can make the motor sound like the whole big end is shot and about to explode.

 

[Roostabunny]

Roostabunny - no I do not feel any more vibration than I have experienced riding any of these bikes over 30 years. I always feel a bad vibe patch somewhere around 3,750 to 4,250 revs but it is never intrusive. No it seems to me that all this clutch noise simply goes away when the bike is ridden or revved highly which comforts me when I am cruising at 80 mph on the highway. Obviously difficult to hear anything at speed.

If you are still not clear where this noise is coming from you can narrow down the area by using a doctors stethoscope device to listen to different parts of the motor when it is spinning. Or you can do what I do. Take a 2 foot piece of 1" x 2" timber. Put one end firmly on any part of the engine whilst it is running and put the other end firmly on the ear bone (or on the little flap in the centre of the ear). You will hear every single thing. Listen to other motors to compare sounds. You can eliminate cam chain thrash, cam shaft bearing problems and a host of other potential noise producing problems like this.

And never underestimate the potential of a good carb sync to eliminate a lot of engine rattle. Just having one cylinder slightly out can make the motor sound like the whole big end is shot and about to explode.

I bought a cheap mechanic's stethoscope, but I think my ear needs training - every location sounded the same to me. I'll pull it out again, might have more success now that I've had a few months to calm down. Just wish I had some other GS's to listen to.

I'm a semi-obsessive sync-er, but that was and still is on the list of things to check. A recent pre-noise repair was fixing an intake leak from a munched airbox boot and aging weatherstripping (from my original airbox rehab). BUT, I have to think that a sync was on my list prior to complete re-assembly on that job. I just don't remember.

 

[londonboards]

Not sure if you will get the low end (low frequency) rumbles with a stethoscope. Try the piece of wood trick. Push hard against the ear bone. You can hear and feel it all at the same time.

Greetings