Gs 1200 final drive design

[Rob-Roamin]

Can anyone verify whether the latest final drive design on the cam head 1200 (ie post April 2010 with steel wheel flange and redesigned wheel side casing with breather) has been redesigned such that the large main bearing is now lubricated by the crown wheel oil bath

I bought bearings and seals from Motobins and the main bearing (33117722799) is not a sealed bearing
the BMW part diagram (33-1627) shows this as the correct bearing and also indicates there is no seal between this bearing and the oil bath

The parts diagram for the earlier design has a sealed bearing and an additional seal between the bearing and the oil bath

I haven't dismantled the final drive as it is still OK (bought the parts as preparation for future maintenance)

I have queried local BMW workshops and Internet forums however I haven't found any definitive information to verify what appears to be a design upgrade

If the bearing is now lubricated by the oil bath I would assume it should have a longer lifespan than a sealed bearing lubricated by grease??

 

[Greenman14]

Are you a natural pessimist, or just being prepared, or are spares hard to come by in your neck of the woods? Whatever, I'll be interested in the answer as my FD oil came out a funny colour, looked like contamination with moly grease to me.

 

[Rob-Roamin]

Are you a natural pessimist, or just being prepared, or are spares hard to come by in your neck of the woods? Whatever, I'll be interested in the answer as my FD oil came out a funny colour, looked like contamination with moly grease to me.

BMW Australia doesn't always have parts in stock and it can be 3 to 6 weeks to get parts from Germany if ordered through a dealership

My bike just turned over 90000 kms and I am preparing for some "preventative maintenance" so it will go another 90k - the final drive bearings and driveshaft universals have a service life and in my mind it is better to replace them before they fail

- as BMW doesnt specify a service life for these parts you have to make a call on when to replace (if you subscribe to the preventative maintenance school of thought)

I am trying to find someone who has dismantled one of these later model FD (2010 on) so I can confirm whether the bearing is lubricated by the gear oil

I am about to head out on a trip and would prefer not to be held up getting a FD fixed

Your oil sounds fine - others have reported moly contamination when the original oil is drained

 

[Bendy toy]

I had my Mk2 final drive rebuilt at about 80K Kilometres. MikeyBoy said all internal bearings were at end of life. I also needed new paralever bearing set and a new U/J at back end of driveshaft.
So to answer the OP.
When my wheel bearing failed the FD oil was not contaminated. My guess it's oil lubricated.
If the wheel bearing side play is within service limits - the tour should be safe. However based on my experience it would be wise to rebuild the FD as a precaution when you return.
For detailed advice about bearings ask MikeyBoy or Steptoe.
However the job requires special fixtures and tools. A thread by PatZx shows how the job is done. Admittedly on an older model FD but principles are the same.

 

[Greenman14]

Can anyone verify whether the latest final drive design on the cam head 1200 (ie post April 2010 with steel wheel flange and redesigned wheel side casing with breather) has been redesigned such that the large main bearing is now lubricated by the crown wheel oil bath

I bought bearings and seals from Motobins and the main bearing (33117722799) is not a sealed bearing
the BMW part diagram (33-1627) shows this as the correct bearing and also indicates there is no seal between this bearing and the oil bath

The parts diagram for the earlier design has a sealed bearing and an additional seal between the bearing and the oil bath

I haven't dismantled the final drive as it is still OK (bought the parts as preparation for future maintenance)

I have queried local BMW workshops and Internet forums however I haven't found any definitive information to verify what appears to be a design upgrade

If the bearing is now lubricated by the oil bath I would assume it should have a longer lifespan than a sealed bearing lubricated by grease??

In your position I'd do the same. I hope there's an equal to Mikeyboy in North Queensland. Good luck with the rebuild and the trip.

 

[Mistacat]

The twin cam wheel side FD bearing is now in the oil bath, but they can still fail.
Not as frequently as the Mk1 and Mk2`s which failed mainly through being pressure washed down and put away wet. ( bearing corroded).
Easy job to change the wheel side FD bearing, Just need to make a couple of tools and follow the BMW manual. ( Don't even have to remove the FD from the bike).

 

[stonehenge]

Mike (Mikeyboy) told me to make sure that 200ml of oil is used in the Final Drive as 180ml does not cover the bearings adequately. I change the oil myself, every time I change the rear tyre.

 

[Rob-Roamin]

The twin cam wheel side FD bearing is now in the oil bath, but they can still fail.
Not as frequently as the Mk1 and Mk2`s which failed mainly through being pressure washed down and put away wet. ( bearing corroded).
Easy job to change the wheel side FD bearing, Just need to make a couple of tools and follow the BMW manual. ( Don't even have to remove the FD from the bike).

Have you replaced the FD main bearing on a twin cam with the FD installed on the bike? If so have you got any pictures you can share

 

[Mistacat]

Sorry no photos.
Remove the calliper, sensor, cover screws etc. I machined a boss with internal thread which is a push fit into the brake side of the FD centre bore.
Using a slide hammer screwed into the boss from the wheel side remove the crown wheel and cover assembly.
Either construct / buy appropriate flange puller, If using a press support the cover plate very well. I use an old brake drum which I milled the necessary recesses in.
Follow the BMW recommended heat settings and cool the bearings.
If in the UK I would suggest that you drop it into Mikeyboy or Steptoe.

 

[Bendy toy]

Make sure anything press fitted is heated to 100 degs C before trying to pull it off. They are a tight interference fit. I used a heat gun and IR thermometer when doing my FD paralever bearings.