Wobbly clutch. Can anyone venture an opinion on this one please?

Checking the ball in the actuator mechanism at the gear lever end of the main shaft is the
easiest and I would suggest you do that first.

Taking the clutch off (again?) is a bit of a pain !

I came across the advice to reduce the torque spec on clutch centre nut after I put my new clutch hub in. So mine is at 70lb/ft. Seems happy.

If all else is correct, it may just be the art of adjusting the clutch. I had two difficulties. Initially, I think I failed to properly position the clutch operating lever correctly when I hooked the clutch cable back up (the lever in the gearbox outer, attached to the clutch cable) and it was very stiff, messing up clutch adjustment. Once sorted, I was still not able to set the clutch adjustment properly with the workshop manual approach, it couldn't tell when the pushrod was just starting to touch the lever. I ended up with either drag or slip. I found the easiest way was to stand gearbox side, put my finger through the gearbox inspection hole, to feel the free play and reach over to screw the pushrod adjuster. I set it at 1/8"" play in the clutch operating lever and then tightened the pushrod locknut. Got it right first time with that approach.

Staytite said:

Checking the ball in the actuator mechanism at the gear lever end of the main shaft is the
easiest and I would suggest you do that first.

Taking the clutch off (again?) is a bit of a pain !

Click to expand...

Shall do.

looking at the video of the clutch center, with the adjuster, clearly rotating out of round brought up a fleeting thought I have had for a long time. Here is the question:

With the clutch rod adjuster removed can the clutch center be persuaded with a light hammer into center? I would appreciate any input. Tomorrow when I get to my shop I have a Commando with its outer primary cover off...

Best.

TerryW said:

Shall do.

Click to expand...

Check that the actuator arm did not drop down during re-installation. Should look like this



For the other bits:

gortnipper said:

Check that the actuator arm did not drop down during re-installation. Should look like this

For the other bits:


View attachment 82221

Click to expand...

Yep, that's what I was trying to say. I found steps 5 to 7 didn't want to work for me. So, once I released the lock nut (as per 5), I just went back to step 4 and adjusted, until I had 1/8" free play in the clutch operating lever in the gearbox cover.

I ripped the mechanism apart and checked it over this evening. All back together now. Tested it by pushing the fork where the cable fits and it is smooth and works well. After adjustment the adjuster screw the clutch end is still sticking out way too much. The mechanism looks the same as in the photos.

TerryW said:

The mechanism looks the same as in the photos.

Click to expand...

The cable doesn't look straight so the lifter mechanism probably isn't correctly aligned with the clutch cable entry and the actuator arm is normally closer to the outer case (my pic in gortnipper's post).

I can re-align the clutch cable. No problemo. Lever position might be more difficult but I'll see what I can do. NB the mechanism works I.e. it pushes the lever across when the cable pulls the fork up. When I put it together I made sure that the ball was engaged properly etc. You have to sort of hold it all in whilst winding in the securing gizmo.

TerryW said:

I can re-align the clutch cable. No problemo. Lever position might be more difficult but I'll see what I can do.

Click to expand...

If you realign the mechanism then it will probably correct the actuator position.

Setting the actuator in perfect alignment helps reduce the force needed to operate the clutch and there's even a special alignment tool.

From the clutch pushrod adjuster in the primary, might for some reason, your clutch pushrod be going further into the primary relative to the main shaft. With the 1.5mm end float on the main shaft and the wobble in the videos, as you said in your initial post, is the problem with what (laterally) locates the main shaft, and the adjuster is just a symptom? If the main shaft is moving about laterally, that might continuously change the relative position of the pushrod adjustment, causing your clutch slip?

champ7fc said:

I have a belt drive on my 71, The clutch adjuster is too far out, I think you may be shy a clutch plate or two. The noise I think is a product of too much moveable space for the plates, take the basket off and count your plates.

Click to expand...

If the OP adds a plate wouldn't that require the rod adjuster to move out even further?

I think you're right about removing the plates, it wouldn't surprise me if the hub and basket were notched, if they are the originals then I'd put the probability near 90%.

I reread the post and couldn't find any reference to the model year, could be my eyes? I make this remark because it may have the wrong pressure plate?

I suspect that the solution should be easy to define, doesn't mean it won't be expensive...

Best.

Mart UK said:

From the clutch pushrod adjuster in the primary, might for some reason, your clutch pushrod be going further into the primary relative to the main shaft. With the 1.5mm end float on the main shaft and the wobble in the videos, as you said in your initial post, is the problem with what (laterally) locates the main shaft, and the adjuster is just a symptom? If the main shaft is moving about laterally, that might continuously change the relative position of the pushrod adjustment, causing your clutch slip?

Click to expand...

Hi, I fixed the end float problem. The mainshaft nut had come undone. Ta.

RoadScholar said:

If the OP adds a plate wouldn't that require the rod adjuster to move out even further?

Click to expand...

No.
If, however, there was a plate missing then the clutch pull would be extremely heavy but no signs of that in the videos.

RoadScholar said:

I reread the post and couldn't find any reference to the model year, could be my eyes?

Click to expand...

Appears to be an 850 Mk2/2A from the videos.

Any idea of what your torque was on the nut that loosened? What was your reinstallation torque?
I ask because this has happened to me.

In discussing how far the adjuster sticks out.....

The OP has a non-standard, source unspecified belt drive. Are the dimensions 100% as per a standard triplex chain drum item? (and as suggested by others are the correct clutch plates/pressure plate fitted and is the centre in good condition?)

Is the pushrod itself a standard Norton item or length? People do make them out of 1/4" or 6mm rod. From varying materials, Sometimes hardened ends, sometimes not!

If the clutch adjuster nut is adjusted without first fully slackening off the cable, isn’t it possible to end up with the adjuster incorrectly far out due to the actuator arm not being allowed to be fully ‘out’ ?

Hi,

Please remember that this isn't a fresh installation of a new belt drive and clutch. The bike has been run by me for several thousand miles (over two years) and the clutch/gearbox has worked well.

An issue became apparent when I saw dust/scrapings from the drive belt in the chaincase when doing stroboscopic ignition timing after fitting a trispark unit. I discovered a load of endfloat on the gearbox mainshaft (1.5mm measured on a steel rule).

With your help I traced this down to the mainshaft nut being undone. I torqued the nut up and put the clutch back. End float gone.
When investigating the endfloat I took the clutch basket apart to check the clutch bearing. I think that I put it all back as it came apart.

I followed the adjustment procedure (above) and I get a very nice gear change and light clutch lever. It always was very light and I have never had clutch slip. It has occasionally been a pig to engage 1st gear but they all do that from time to time.

Now, I have the issue that over 70mph the slack in the clutch cable magically disappears. When I slow down again and pull in the clutch, the slack re-appears. I have checked the actuator in the gearbox outer cover several times. It is absolutely perfect (even the cable angle). Next thing for me is to strip the clutch down and check that I didn't bugger something up.

Now, I checked the dimensions of a few things: clutch centre adjuster (16 threads) - cool. Clutch rod. This was 9 - 7/8ths rather than 9 - 13/16ths. I am working on the theory that this would push the adjuster outward 16th of an inch which is not very much. It is 6mm diameter and not 1/4" as it should be.

TerryW said:

It is 6mm diameter and not 1/4" as it should be.

Click to expand...

6mm is correct. Edit Unless perhaps you meant: It is 6mm diameter as it should be and not 1/4".
Factory manual, Section A, Primary Transmission and Rear Chain,