yep........yamaha

I'm in agreement with that :icon_thumright:

Polybush rear drives is what we need..

My cush drives are also far worse and only covered 5k - been shimmed with inner tube too and I have a new set to destroy courtesy of a warranty claim.

cush drive
 

I have installed a second bearing in the sprocket holder. There is enough "meat" to make the bearingchamber 15 mm deeper for a second bearing. One other thing to do is making the little spacer fit by milling off 15 mm too. The result is the same as filling the cush drive with rubber, but I don't like that.

+1 for polybushes :D

not a slly idea... urethane is very easy to mold...
Its a cold to part mix.... if yer used something
around Shore 95A... even the mold could be
made from nylon..easy to machine up..

The XT ones could be cut from urethane sheet..
a hacksaw with a well lubecated blade would do it..

Cush Drive Rubbers
 

I had these made up out of Polyurethane

http://i127.photobucket.com/albums/p...0-07101358.jpg

http://i127.photobucket.com/albums/p...1-10104855.jpg

I have 25 000 km on the set that are in at the moment and they look as good as the day I fitted them

http://i127.photobucket.com/albums/p...9-23170241.jpg

I have sold a lot of them too R650 South African Rands per set

Cool!
How much?

Nice one, well done mate. I thought somebody would be able to find someone, somewhere who could do it.

What hardness of polyurethane did you go for in relation to (a fresh) set of rubber ones?

A few Dutch riders (I'm one of them) have modified the sprocket-carrier such that it can take either a double Yamaha bearing or a single wide BMW wheel
bearing, with good results.

Here's a link to some photo's showing the double Yamaha bearing solution: http://www.motor-forum.nl/forum/list...46525#21446525


This is the BMW part no. 36 31 2 310 972 (used in some BMW front wheels)
inner size is 25 mm
outer size is 52 mm
with 20,6 mm (5,6 mm more then standard and with double row bearingballs)
You'd have to make a new socket!
€32,-

It's actually a INA 3205-2RS F0712 or SKF 3205-2RS

like http://www.amazon.com/32052RS-Bearin.../dp/B002HARCP2

http://ecx.images-amazon.com/images/...500_AA300_.jpg


Last time I checked the rubbers didn't show any wear after a few thousand km's. Normally you'd see rubber flakes and worn blocks.

EDIT: I only just noticed Salami's post ...

HJ