My final drive was completely overhauled with 'ALL' bearings and seals replaced 12,000 km ago, due to the fact that it was very noisy and had significant side-way play at the wheel. On removal, it was discovered that the pinion bearings were worn too, exhibiting excessive play.
Just returned from a 10,000 km ride across Australia and back, carrying full touring load.
The oil is still on the inside where it belongs...
FIRST: Make yourself fully aware of the entire process. Do your research!
NOTE: Four (4) special tools are absolutely essential.
If you cannot borrow or acquire any of these, do not undertake this task!!
1. SHOW STOPPER: A hot air gun. Do bear in mind that water (spit) boils at 100 degrees Celcius.
2. SHOW STOPPER: 'Pinion bearing' retainer nut tool, a BMW special tool. This retainer also houses the pinion seal.
3. SHOW STOPPER: 3/4" drive 36mm deep socket for the 'Pinion' retaining nut.
4. A hydraulic press is also a good tool to have access to.
The remainder can be relatively-easily fabricated or worked around. Check the ADV Rider website for references.
Issue 1: 'Pinion' retainer nut (36mm)
This requires a jig to be fabricated. Drill 2 holes in a work bench. Clamp the complete final drive housing to the bench similar to the photo. Drill 2 holes in a steel plate / bar and bolt it to the wheel flange. Using a 3/4" drive 36mm socket (deeper than standard to accommodate the pinion input spline), undo the 'pinion' retaining nut. It is torqued to 200nm and thus will be very tight.
Photo showing undoing the 36mm 'pinion' retainer nut with the final drive housing complete in a home-built jig and wheel flange retainer.
Issue 2: 'Pinion bearing' retainer special castellated nut. It is the castellated part around the outside of the pinion retaining 36mm nut in the second image above. This cannot be undone without the BMW special tool. It is torqued to 180nm and is very tight.
If you cannot borrow or acquire one, do not undertake this task!
As at February 2015, there were none in Australia and 2 left in USA.
Max BMW USA: https://www.maxbmwmotorcycles.com/fiche ... %201%20711
Issue 3: Roll pin - 2mm x 38mm
This roll pin locates and retains the pinion nose bearing.
Photo showing housing; roll pin installed; roll pin removed; removal tools; and inserted drill bit / paper clip; attached vice grips; attached slide hammer.
A paper clip was used in this instance. A hardened drill bit would have been a little kinder on the roll pin. However, it did clean up OK and was inverted on assembly.
The roll pin is not listed in the BMW R1200 parts list or workshop manual. A 2mm roll pin this long is also not available at hardware stores (max length = 25 mm).
If you break it in the hole, a spark eroder will be the only way to remove it from the blind hole in the housing. Big $$$$. I only found two other references to this on the web. One of which was about the cost of breaking it in the hole and the other about how to correctly remove it without breaking it.
This leads me to believe that not many people actually replace the pinion bearings.
Why?:
Nil availability of the roll pin (3 months ex-Germany)
There is a extensive references to replacing the crown wheel bearings and seals but little about the pinion bearings and seal.
Example 1: http://www.roamafrica.co.za/forum/index ... pic=1560.0
Example 2: http://www.advrider.com/forums/showthread.php?t=532127
Example 3: http://www.adventurebikerider.com/forum ... rhaul.html
Example 4: http://www.advrider.com/forums/showthread.php?t=682413
Very short supply of the 'pinion bearing' retaining nut tool (Note: Not 'pinion' retaining nut tool which is just a deep 36mm socket).
Example of Spark Eroder in action: YouTube
Spark Eroder / Metal Disintegration Machine
https://www.youtube.com/watch?v=YbeKxFBZrF8
Example of a Service Provider: Furmanite
http://www.furmanite.com.au/services/on ... -services/
Issue 4: Removing the pinion nose bearing from the housing.
The housing needs to be heated to remove this bearing. It's easy enough to fabricate a puller that will attach to the end of a slide hammer. Grind down a stack of washers to the correct shape to fit inside the pinion nose bearing. When you see it, you will understand.
Photo of Pinion Nose bearing removal tool attached to a slide hammer.
Other Observations:
a) The large crown wheel cover was corroded at the bottom up to the edge of the cover sealing o-ring.
b) The bottom 3 crown wheel cover bolts were badly corroded. These were difficult to remove. There is no gasket at this joint, just the crown wheel back lash adjusting shims which do not prevent dirt, water, salt, etc from seeping in around these parts.
