Cush drive free play

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Just installed 6 new cush drive pieces. After a brief ride, can move wheel against locked rear brake about 1 inch at the tire . They fit easily on install. Too easily? What is acceptable movement?
Doug
 
Use better wording please. 1 inch of slop with new cush drive blocks is worse than worn out old ones.
 
Douglas, there shouldn't be any play at all of the sort you describe. I normally have to hammer the brake drum on with a rubber mallet when fitting new cush drives. I would take it apart and have another look. the flat side of the cush rubbers should bear against the drive paddles and the 'corrugated' side against the alloy hub.
 
Just installed 6 new cush drive pieces. After a brief ride, can move wheel against locked rear brake about 1 inch at the tire . They fit easily on install. Too easily? What is acceptable movement?
Doug
There should be 3 thick and 3 thin. If it went together easily, you either have bad parts or wrong parts! There should ne NO play.
 
Douglass, did the MEAN on the brake? Or in gear?

There shouldn’t be any movement on the brake, but there will be backlash when in gear.
 
I used a plumbers, silicone grease to install.
They disintegrated with in 1k miles.

Anyone use a lube, if so, what type?
 
Have not used grease , yet .... suppose you would want to use the same grease as on the ISO’s the red stuff .... so far a rubber mallet has worked for me as well
 
I used a plumbers, silicone grease to install.
They disintegrated with in 1k miles.

Anyone use a lube, if so, what type?
This is the only stuff I'll use on rubber. Also works well as dielectric grease on electrical things - Cush drive free play
 
This is the only stuff I'll use on rubber. Also works well as dielectric grease on electrical things -View attachment 19193
I love SilGlyde and use it on almost everything. I have a tube in my workshop, a tube in my mobile tool bag and two in the house. Have been using it for years without any problems whatsoever. I have used it for my ISO and cush drive installations.
Wrench On
Dave
 
The fit is very tight, and as mentioned the scalloped sides face the hub, not the paddles. Using grease means the rubbers slide around in the cavity as you insert the paddles. An old trick is to use hairspray which starts slippery then sets up dry and holds the item. However, that method will not provide lube at all, so I typically start with hairspray then coat the paddles just prior to installation with a grease favorable to rubber (Sil Glyde is excellent). Yes, I do need to use a rubber mallet for full installation but of course when you tighten the axle everything gets proper clearances.

If you grasp the chain, both top and bottom, rigidly, you can then move the wheel and check the "slop." Clearly when these parts are new that slop should be absent. I'd have another look.
 
no play here. used a very small amount of silicone grease on the brake hub pins - just a light coating. when I installed my wheel assembly, aligned the brake hub pins, and wiggled the wheel assembly back and forth a bit to help seat the two assemblies. can't say there were any problems. - it just went together.
 
Thanks guys.
Got it mocked up on a stand, dry.
Upon further reflection they didn't disintegrate, they melted after a semi spirited ride through a canyon.
When I returned there was this spider web of goop on the rear spokes in the port side.
Not sure what the issue was as the brake was fine and it rolled freely.

Got it back together, went for short ride. Back drum is HOT to the touch, hotter than the disc, hub is cool.
I use the disc far more than the drum, obviously the shoes/shoe is rubbing. But why, what's different?
It's not an adjustment issue as there is plenty of travel.

The one thing that is different, I added two of the #21 shims to space out the sprocket/drum for chain guard clearance.
This has put the shoe/drum interaction different. Is this the issue, don't know. Something is funky for sure.
Will look into it when time allows.
One thing I do know, 'Everything affects Everything'............
 
Well I'd take an educated guess that your large brake hub circlip has worked itself out of place causing drift. And that means a hub teardown with a new circlip. You have to do it anyways as the blocks overheated and melted and at least the double row bearing will need some fresh ( not cooked ) grease.
 
Just installed 6 new cush drive pieces. After a brief ride, can move wheel against locked rear brake about 1 inch at the tire . They fit easily on install. Too easily? What is acceptable movement?
Doug
I put the old , probably originals , back in and now no play after a ride. They tapped in fairly easily. I guess the new ones are not made right.
 
Thanks guys.
Got it mocked up on a stand, dry.
Upon further reflection they didn't disintegrate, they melted after a semi spirited ride through a canyon.
When I returned there was this spider web of goop on the rear spokes in the port side.
Not sure what the issue was as the brake was fine and it rolled freely.

Got it back together, went for short ride. Back drum is HOT to the touch, hotter than the disc, hub is cool.
I use the disc far more than the drum, obviously the shoes/shoe is rubbing. But why, what's different?
It's not an adjustment issue as there is plenty of travel.

The one thing that is different, I added two of the #21 shims to space out the sprocket/drum for chain guard clearance.
This has put the shoe/drum interaction different. Is this the issue, don't know. Something is funky for sure.
Will look into it when time allows.
One thing I do know, 'Everything affects Everything'............


This is a follow up. I orginally didn't have the correct #21 shims. I did have a washer That would work.
IMG_5155.JPG

Not knowing at the time this washer is little thicker than 3 shims.
IMG_5156.JPG

What this did was push the drum in and the spacer beyond the little torque arm.
IMG_4922.JPG

During a spirited ride the arm pulled off the spacer, cocking the drum and causing overheating.
IMG_4902.JPG

Therefore melting the cush rubbers.
IMG_4842.JPG

I tried using 2 #21 spacers and got some interference. I assume this is from the shoes being positioned different on the drum.
I have since eliminated the #21 shims and gone to a proper sized AN (Army/Navy, not Andover) washer between the swing arm and the torque arm with the arm securely positioned on the drum spacer. I have also gone to a one piece axle.
Problem solved, I have gone several hundred miles, no issues.
 
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