pivot bearings on final drive

[fizzer]

bit of advice please my twin cam r1200gs 2011,has a slight bit of movement ,holding the wheel at six and twelve the wheel has a bit of play,to be honest i thought it was the main bearing but on closer inspection i can see some very slight movement at the pivot bearings in the final drive unit . ,are they a simple enough task to replace
cheers folks

 

[Kenny Rodkiss]

It's a double row ball bearing on the outside and a BMW only ( I think) needle bearing on the inside. The needle bearing has a rubber lip on one end that seals on the bearing pin to keep dirt out.
The other end of this bearing is sealed by a squishy rubbery washer under the flanged head of the bearing pin.
Mines has had movement you can feel but not see, unless you put a smear of grease over the pivot area and watch very closely for movement. Been like that since brand new and has never gotten any worse.
Press fit like normal bearings.
18 and 19 in the second image are the same as 6 and 7 in top image.

 

[fizzer]

many thanks for that kenny ,very helpful

 

[Bendy toy]

When you strip it down you need to get the casing around the pivot (trunnion) bearings to 100 degs C with a hot air gun and IR thermometer.

If the bearings are OK or with new bearings pack them solid with high quality CV joint grease as used in car drive shafts. For rolling bearings this would be very bad news as the grease has no space to recirculate. But this is a rocking bearing so packing it to the brim reduces the scrape away effect of the rollers as they move back and forth a few degrees each way.

 

[fizzer]

ok bendy thanks,i have only a small amount of movement holding the wheel at twelve and six ,do you think a strip and clean and new cv grease packed in would take up the play ,or do you think replace the bearings

 

[fizzer]

also do you know the torque setting of the big bottom bolt

 

[Bendy toy]

Dr Google will find it. http://www.r1200gs.info/misc/torque.html

 

[fizzer]

many thanks

 

[fizzer]

can i also just ask do these bearings come out and go in from either side ,or are the pushed in from a particular side

 

[st247]

One will come out either way and the other will only come out in one direction. I cant remember which but just have a look at the castings on the inner side and you'll spot the difference.

 

[Bendy toy]

If you can feel any play in the bearings they are most likely shot. In a rolling bearing the imposed loads get shared out so they last a long time. In a rocking action the same few rollers get hit all the time. The grease gets rubbed out and the rollers eventually get a flat spot. It quickly goes down hill from there.