wheel bearings

[Mike Wilkins]

can I replace the wanky difficult to adjust taper rollers in a twin shock, with normal ball races of the same external dimensions. If so how can I tell which to get ? If I tell a bearing suppliers the taper spec, could they match it with a ball race ?
Ta
Mike

 

[Redboots]

can I replace the wanky difficult to adjust taper rollers in a twin shock, with normal ball races

There wont be any adjustment in a ball race.

John

 

[Mike Wilkins]

bearings

I dont want any adjustment John, just want to fit and forget. Adjustment is a pain with little 'wedding band' shims to set preload.
If anyone wants a headache, try either of the below and realise why I want to change :
http://w6rec.com/duane/bmw/wheel_bearing/
http://bmwmotorcycletech.info/section4.htm

 

[theschoning]

looking at the description and graph it looks like the taper bearing will last over 2 billion miles even without pre-load (point 2. on curve) - so why bother with 'adjustments'

http://w6rec.com/duane/bmw/wheel_bearing/

 

[Rob Farmer]

I take it that's Snowbums graph.

Don't forget the rear needs shimming as well. I bought the gear to do it myself. To be honest it isn't difficult. The biggest eye opener is just how far out most peoples shimming is. If you do it by feel you end up much too loose.

 

[Mike Wilkins]

bearings

I need to do the rear Rob
Mine has play - more than enough to fail an mot I think. Some muppet PO has put it together with NO SHIMS !! This makes no sense to me as I would have thought inner races closer together means tighter ????
Anyhow I dont have time to arse around with it I just thought why not replace the tapers with normal - seems logical to me or am I missing something. Doesn't need to be adjustable its not on GS or later cast wheel airheads
CHeers
Mike

 

[Rob Farmer]

Too tight a fit will cause spalling on the bearings. The lubricant is forced out by the high pressures generated by the rollers.

You just need something like this http://www.uni-max.co.uk/torque-screwdriver-4-nm-28pc-set/d/ with an adapter to take a 19mm socket and a 2.5 inch tube to fit over your wheel spindle.

I picked up a couple of toque screwdrivers on ebay for 99p each and a new calibration gauge for £25. Buy a small range of wedding bands either side of 6.8mm and you're away. The whole set up should cost you around half the price dealers would charge you to do one wheel. Once they are set properly you should find they last for years and your bike doesn't shimmy across ridges and white lines.

 

[Mike Wilkins]

Trouble is Rob this is a bike I have no interest in and dont want to spend much time on, just want rid of it and rather play with my GS or XRV (which I recently crashed and now needs major surgery - thats what I should be doing)
I dont intend to have another twin shock so have no need for shims and special tools.
Surely if I replaced the tapers with sealed ball races (like on the xrv) and they were a snug fit on the spindle and in the hub, this would remove the need to tit around with shims for ever more - any good reason why not ??

 

[Beemerboff]

You would need deep groove ball bearings, of course, and I think you would still need a spacer between the bearings so that when you tighten the nut on the end of the axle you are not pulling the LH inner race sideways,and also to clamp the stack so that the bearing inners do not turn on an the axle.

 

[Beemerboff]

Shouldn't tempt providence - I am giving my 86 G/S a full service, should be its 20 th at 320,000 km, and one front wheel bearing feels a bit rough.

A big bit rough and needs replacement soon.

Depending on what you read it either has the 30203A taper roller or the equivalent deep ball, a 6203 2RS in C3 grade.

Not really a problem for the bearing as I work close to a good bearing factor, but if I have the taper roller the preload spacers "wedding bands" are a problem - anyone know if there is any reason I cant just buy a few 17mm shims and adjust the preload by either filing the wedding band a bit shorter or shimming it up , or both.