Cush drives (again) - Hub and Sprocket Carrier Wear
 

I had the rear wheel out to shim the rear suspension relay arm and whilst i was there I properly checked the play in the cush rubbers. Prompted by Pleiades view that 7,000 miles was about the cush drives limit.

Despite me saying a few days ago they seemed ok on closer inspection they're not and there seems to have been some contact between the hub and sprocket carrier.

http://www.sweller.dynalias.org/images/xthub1.jpg

http://www.sweller.dynalias.org/images/xthub2.jpg

The Wemoto pattern cush rubbers that were in there had done 10,000 miles and had a fair bit of play. I replaced them with the OE ones I took off earlier last year that had 5,000 miles on them (I also shimmed them with some old inner tube). They'll do temporarily.

Looks like I caught it in time - I'm off to Chemnitz this weekend on it too!

http://www.xt660.com/showthread.php?t=21930

Hi mate, had the same problem.

The solution is not in the rubbers or packing them with inner tube (although you should do this)

Replace the bearing inside, and get a chain alignment tool to ensure this doesn't continue.

Cheers - I checked the wheel bearings when I had it apart and they felt fine. Very smooth with no roughness or play.

They are SKF bearings and were replaced 10,000 miles ago so should have some life left in them.

I'm also pretty particular about chain adjustment (I use a metal ruler to set them).

Looks like I'll be replacing the bearings fairly soon - as I can't see any other reason for the side-to-side flex. I suspect the fritzed cush drive rubbers may have put too much load on them.

I checked mine at the weekend and they were in a far worse state than the ones in your thread http://www.xt660.com/showthread.php?t=21930 My bikes only done 4800miles? I should have taken a photo, the raised circles on one side are completely worn away and I could twist the sprocket assembly a couple of mill taking up the slack. All my bearings and chain alignment were fine.

I've packed them out with an inner tube from my kids push chair after reading other posts.

Does anyone make a heavy duty version? A lot of my bikes have had cush drives and I've never known them wear this quick.

Don't trust the markings on your swing arm for making sure the chain is aligned. Get your self a proper tool for the job
http://www.motionpro.com/motorcycle/partno/08-0048/

This way you can check the chain is true between the sprockets.

Would suggest that even a couple of thousand miles with a slack chain and perished rubbers is bad for the bearing and carrier (lots of torque on that back wheel, and you'll use clutch slip a lot on the stock 660)

There was someone making heavy duty rubbers, but he seems to have slipped off the radar for the time being.

When packing out the rubbers with inner tube, it should be almost impossible to get it back together. Use fairy liquid and a big rubber mallet, or the old zip tie method.

Cheers for the advice WeaveMcQuilt I've just ordered a chain alignment tool so will check when it arrives.

Even with a section of inner tube in each quarter of the cush drive I was still able to push on the carrier without too much trouble?

They're probably much better suited to an asthmatic, but silky smooth 20hp V-twin, rather than our lumpy 45hp singles. ;)

So what ever did become of those South African urethane rubbers from a year or so ago?
Anyone?

I cut thin metal plates, maybe around 1-2 mm thick and placed inbetween the cush rubber blocks and the metal block in the hubb where the rubber block layin against.

The cush rubber blocks lasted approx 40 k km on my bike in this way. Its 2-3 times as much as normal. Its quite easy and simpel to do and is worth a consideration.

Should have shown som pics here but didnt have a phone at hand when I was changing these things....

Poly rubbers
 

I bought a set of poly rubbers from Andy Ross in late 2014. Had to chase him up several times after paying by PayPal and nothing turning up, however after a phone call they did arrive. If you want to try him his email is accentgt8@gmail.com