Rear swing arm bearings... stuck

Thanks Guy's.. and where might we get any of this 60% moly grease from... maybe bearing services etc?
 
you see thats the problem.. from £50 to £3.80.. that can't be the same stuff.. and the other one is from the US?....
 
Bearings on the paralever to bevel box of my gsa lc were shot at 13,000 miles , the needle rollers were all but totally dry, reason given by BMW technical that they do not lather the bearings with a decent grease,
' Customers do not like to see grease oozing out of joints on their new bikes as it spoils the looks and attracts dirt', followed by the old chestnut of 'If you over grease the bearings they skip on the races and do not function correctly '
 
you see thats the problem.. from £50 to £3.80.. that can't be the same stuff.. and the other one is from the US?....

Exactly. The Rocol will be a dry lube. The greases have a much lower moly content. I doubt if that fabled 60% even exists. One grease quoted 3% moly. Rocol Aerospace greases are large amounts of money and many of the features (ultra low temperatures etc) are not needed on a bike).

I settled on a "high moly" grease sold for use in drive shaft CV joints. They take a hammering so I reasoned it should be good enough for a bike's suspension bearings.
 
OK.. I think this thread is getting confused.. will start a new one on grease for splines.. thaen we can keep this one for swings arm bearings... :)
 
Bearings on the paralever to bevel box of my gsa lc were shot at 13,000 miles , the needle rollers were all but totally dry, reason given by BMW technical that they do not lather the bearings with a decent grease,
' Customers do not like to see grease oozing out of joints on their new bikes as it spoils the looks and attracts dirt', followed by the old chestnut of 'If you over grease the bearings they skip on the races and do not function correctly '

Rolling bearings as in wheel or gearboxes should be grease filled to 50% allowing enough room for the grease to move as the rollers turn. Oscillating bearings will quickly rub the grease away putting metal to metal over a small area of bearing surface. Pretty soon the rollers are flatted and its all gone to hell in a hand cart.

The reality is that BMW traditionally use rolling bearings in the suspension. They are cheap and easy for them but they are not suitable for the job. Bronze or polymer (IGUS**) bushes would be far better but that's not biker tradition and probably more costly for the factory. Even rubber (or poly) bushes as used on cars would be a better bet. They don't have to be wobbly.

Our only option is to pack the suspension bearings with a high solids moly GREASE and hope that enough gets wedged under the rollers to keep metal away from metal.
 
The JMC swinging arm in my Katana has been on the bike since 1985 , it uses substantial taper roller bearings (same as a bikes steering head bearings) with sealed end caps , they have been stripped out and regreased 3 times and still show no signs of wear .

Correct bearing specced for the job will probably last another 30 years
 
The BMW has quite a short radial movement but as you say the bearings are tiny. The Paralever bearings at the back end (and the front front swing arm bearings) have a very small angular movement. The rubbed contact areas on the small angle bearings do not even meet.
 
So best grease for the bevel box bearings and needle bearings is Moly again... the CV stuff or the 60% stuff... got to say, the 60% stuff is like paint.. get it on your fingers and it just won't come off.... great stuff....
 


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