Possible Clutch Problem

[bassman]

Hi all, haven't posted for sometime, just been riding and maintaining the bike!

Thing is, I'm starting to wonder if I've got a problem with the clutch (hopefully not the gears).  When I changed the chain and sprockets back in the summer, I inadvertently stretched the spring that returns the clutch mechanism to its resting position (I'm talking about the thing inside the clutch cover that pushes against the rod that dis-engages the clutch - the actuator you could call it I guess!). I've ordered a replacement that I will fit at the weekend.

The clutch works perfectly fine but there a little bit of a clonking sound from the general area of the clutch when I let the clutch out when I've changed gear.  It's mainly when changing to 1st/2nd gear. It probably is just that stretched spring cause the noisy operation, but has anybody had a similar problem not related to a dodgy spring?

Since writing the above I have done some research on the forum and found a good article with pictures of the actuator and the ball bearings within. When I get the new spring I will take the actuator apart and check the ball bearings are in place (there are several which sit in a conical groove within the body of the actuator). When I last took it all apart when I changed the chain/sprockets, I didn't really pay enough attention to what I was doing and may have messed up the mechanism (got 'me little balls out of whack!).

Bassman

[bassman]

Took the sprocket cover off today, cleaned all the oily gunk out, removed the mechanism that releases the clutch and checked it out. All eleven ball-bearings were in place.  I cleaned the old grease out and re-greased it, refitted it to the cover and fitted the new return spring (the one I had inadvertently stretched). I bolted the cover back in place and adjusted the mechanism (through the external access panel - the one held on with two cross-head screws) and the clutch cable freeplay.  I haven't ridden the bike on the street yet, but I did short take-offs in my back garden and the clutch seems OK. I reckon it just needed the new spring to bring the clutch actuating mechanism back to it's proper resting position.

Bassman

[bassman]

I think there is a problem with the clutch after all! Any suggestions are welcome

Here are the symptoms:

1) When I let the clutch out after changing gear there is a slight 'snatch' like the clutch is slipping slightly before fully engaging.
2) Whatever gear or speed I'm going at, if I drop the revs right down then rev up quickly quick hard accereration) it does that subtle 'snatch' again.
3) When I wheeled into the back garden (engine off) I put it into 1st gear, let the clutch out to make sure it was in gear, then pulled the clutch and tried to push it. The clutch stayed engaged until I rock'n'rolled the bike a little.  It then disengaged and I could push it relatively easy (but not as easily as when in neutral).

Bassman

[JAY W]

Might be worth checking the output shaft splines being worn where the front sprocket fits,this will give the snatch you describe.It wouldn`t be the first GS to develop this,have wondered if bearing retaining fluid would help in this situation as a temp` quick fix,better still using retaining fluid when putting a new sprocket on a good shaft to prevent.(chain being slack with lots of lash is prob` the culprit) Hope this helps and i`m not just ranting.

[the mole]

3. is normal behaviour, wet clutches have a bit of drag even when fully disengaged.

1. and 2. could be a chain and/or sprocket problem as JAY W said.

[bassman]

Thanks for the comments guys - any input is really appreciated! However, I'm pretty sure it's not the chain/sprockets that are the problem. Plus, the drag when pushing the bike in gear with the clutch pulled in is way over what it has ever been before (I just pushed my Yamaha 600N in the same manner and no problem at all). I would struggle to bump-start it in this condition. I've had the bike for just over 3 years and put about 16-17,000 miles on it riding to work every day (it's around 21,000 total mileage). It's never been like, it's always been so light to clutch and is great for commuting.  I'm hoping that it'll just need new thrust washers/release bearing. If I need to replace the friction/plain plates they're not too expensive.  I'll have to fashion the tool described in the Haynes Manual to hold the clutch centre when I'm working on it. I don't mind doing the work - but discovering the problem now when the wintrer is about to dump the first snow of the season is a real bummer - I have to work outside !

Oh well, at least I'm lucky enough to have a bike to work on in the first place!

Bassman

[bassman]

I've given the grey matter some bashing and I've decided it's best to try all non-invasive solutions before dumping the oil and pulling the thing apart. I'm going to tie the clutch lever open and warm the bike up. Then I'll remove the sparkplugs so I can easily turn the engine over with a wrench and remove the oil filler cap so I can get a good view and access to the part of the clutch housing you can see. I've got an idea (from observations) that it may be that first four or five friction plates are stuck together. While rotating the engine gently with the wrench I'll try to gently release one friction plate at a time. If doesn't work at least I've tried!

Update: It didn't work! I could easily loosen the four plates I could reach so either the ones I cant see are sticking or the thrustwasher thingummybob is sticking, or maybe a mouse has taken up residence in there. Oh well - time to get messy!

Bassman

[bassman]

I am cautiously optimistic that I have sorted the clutch (without dismantling). Riding home on the yammy today I had an idea - what if I warm up the bike and then deliberately stall it (at a standstill). Letting the clutch out in a semi-controlled stall might be violent enough to loosen the plates. Well, I did it a couple of times (I didn't enjoy abusing the bike) but it seems to have done the trick! I will not know 100% until I ride to work tomorrow, but pushing the bike in 1st gear with the clutch in has definitely improved. I've tied the clutch in for the night and will ride to work tomorrow (snow allowing!).

Bassman

[skirecs]

can't some clutch plates wear a notch in the basket that could cause sticking?

maybe i'm thinking of something else

[bassman]

Your're right - they can. It is apparently possible to dress the basket with a file if the notches aren't too bad. The plates can also warp and stick. I'm hoping they were just stuck together and that I've sorted them (fingers crossed!) - I really don't want to delve into the innards of the bike at the moment!

This all started a few months back. The bike was laid up for about three weeks in the summer while I sourced a new chain and sprockets and equipped myself with the necessary tools for the job. The first time I tried the clutch after assembling everything ther was a loud 'crick' sound as the clutch disengaged. It disturbed me at the time but the bike ran OK so I forgot about it.  But then I noticed the funny 'crick' sound more often and then the snatching sensation when changing gear. It is always possible one of the pressure plate springs is broken - which could cause the plates to bind I guess.  But the bike has only done 21,000 miles in the last 10 years so one would expect the clutch to be good still!  My Yammy has done 35,000 miles and the clutch is still good (similar design).

Bassman

[bassman]

OK, bad clutch it is! Rode to work yesterday and, although slightly improved, the 'snatch' is still there.  Have ordered new friction plates and stronger springs (EBC), clutch cover gasket and thrust bearing and washer.  Once the snowy weather passes I'll sort it (might have to wait 'till Christmas now).

Bassman 

[bassman]

I sorted the clutch today. Skirecs - the clutch basket was quite notched after all! The friction discs were also pretty well shot. Couldn't take pictures of operation beacause of time/daylight being short, plus it was really cold working in the garden! I dressed the clutch basket with a small file just enough to improve it without filing the notches out completly. When fitting the pressure plate (using my torque wrench as directed by the manual) I was concerned that one of the spring bolts was over-tightening. So I just hand-tightened the bolts (I mean I used my judgement rather than using the torque-wrench). When reassembling the cover I overtightened one of the clutch cover bolts (again using the torque wrench!) but I was able to withdraw it from the cover without it completely breaking off! Lucky!!!! I replaced the whole thrust washer assembly as well, although I only needed to replace the thrust bearing (but I had purchased all the parts so decided to use them).

Most important lesson from all this? Just because some bolts on this bike are subject to heat, vibration and oil, beware of over-tightening them because they are just too poor quality and weak and it is not necessary to torque the life out of them! I thought I had already learned this lesson but it would appear not!

Bassman

[bassman]

Update !

Although clutch is better in that there is no longer any drag, gear changing and large throttle changes are still 'snatchy'. After further research I am almost certain now that the cush drive rubbers are the problem! The bike has only done 20,000 odd miles, but it is 10 years old and I suspect the rubbers have degraded. I've ordered some and hope to fit them next weekend. I'll update once I've fitted them.

Bassman

[Toogoofy317]

Degraded rubbers are never good! I'm sure alot of guys can verify that!

Mary

[Paulcet]

You so naughty! 

[tb0lt]

Clutch? What's that?

Degraded rubbers are never good! I'm sure alot of guys can verify that!

Mary

Yeh it's more engaging and fun to skip it and just "shift it" at the right time anyway. 

[bassman]

I forgot 'rubbers' has a different connotation in the U.S.A. (what are you lot like  )!

Bassman

[bassman]

The continuing saga of the clutch - I've ordered a brand new clutch basket! Although the friction plates required changing, and I replaced the clutch springs for new stronger ones, I am as certain as I can be that the real problem I'm having with the snatchy power delivery is down to the clutch basket damper springs themselves (the springs that provide damping between the clutch basket and the primary driven gear attached to it). I reckon they're stress/age/heat fatigued which is allowing the basket too much rotational movement when the load varies during gear changes and large throttle variations. It's causing me to change gear too gingerly which, in turn, makes me slip the clutch excessively. The jerky power delivery must also be putting huge stress on the chain and transmission (not to mention my nerves!). The bike is a good'un so it's well worth spending the money (on credit card ) to get it back to full health. I considered a cheap salvage unit, but I could end up in the same position in just a few thousand miles.

It'll be a couple of weeks yet, but I will try to post pics when I do the work (not that hard - I've done it once already - it's just oily messy!).

Bassman

[bassman]

I finally changed the clutch basket today for a brand-new one.  That means I've completly changed the clutch parts except for the clutch-centre and pressure plate. After setting-up the clutch freeplay correctly it does appear that I have finally sorted the problem. The snatchy-ness has gone and there are no more odd noises issuing from the general area of the clutch/front sprocket area. The old clutch basket looks fine (except for the notches the friction plates have worn) but there is definitely more free-play between the basket and large ring-gear than there is on the new one. I need to make my clutch technique more positive again because I have become a little hesitant and over-slip the clutch because of the problems that developed. The next week riding to work on the GS500 should sort me out! Sorry there are no pics but I was battling gale-force winds and swirling leaves while I was working on it today - the weather here in England has been absolutely terrible over the weekend!

Bassman

[JAY W]

Just noticed your from Derbyshire Bassman,i`m in Northamptonshire.On June 17th the gs500e.uk lads are camping the weekend at the Knockerdown inn near Matlock.