Page 4 of 4 FirstFirst ... 2 3 4
Results 46 to 50 of 50

Thread: 2008 R1200RT - 32,000 Miles - Final Drive Failure

  1. #46
    Nickname: Droid
    Join Date
    Jun 2005
    Location
    Green Bay, WI
    Posts
    2,352
    My 94 RS Oilhead is now at 172k on the original untouched final drive. I change the final drive Castrol Full-Syn 75w90 fluid about every 20k and check for any play monthly. I don't sense any thing about it not making 200k+ on the original FD.

    I'm now in the process of building up my 07 R12RT into my version of a R12RS. I bought the cosmetic crash/clear title RT with only 5900 miles on it, fully rideable, at a great price. I hope to have good luck with the FD on this one, but I'll be watching it closely. Perhaps I'll do the fluid changes much more frequently than I did on my 94RS.

    I have heard though that many failed FDs are due to seal issues allowing water/contaminates into the bearing, or water gets in due to overactive cleaning by owners with pressure washers?

  2. #47
    Registered User 88bmwjeff's Avatar
    Join Date
    Aug 2004
    Location
    Walnut Creek, CA
    Posts
    2,550
    Quote Originally Posted by greenwald View Post
    Perhaps corporate strategy all along was to ignore the problems long enough that consumers would, as you put it, "...look at the rear drive as a replacement wear item."
    It's a cost analysis. If it's cheaper to replace the units under warranty than to change the design, then nothing's going to change. This mentality exists in all companies. However, the breakpoint as to what is acceptable varies from company to company. I find this frustrating. To us, the slightly additional cost seems reasonable, but to the company that is looking at 1,000's of units, the analysis and result is often the opposite.

    On a side note, my biggest concern with BMW is the quality of their parts. I have a 96 328i and an 88 R100 RT, and the quality of the parts I've purchased for my bike or that has been installed via a repair shop with regards to the 328i have been less than ideal. The replacement parts don't seem to be lasting two years, and these are relatively expensive parts (alternator, AC compressor, etc.). What I don't know is whether or not this is confined to the older vehicles like the ones I own or also exists for newer vehicles.
    Jeff in W.C.
    1988 R100 RT (the other woman)
    "I got my motorcycle jacket but I'm walking all the time." Joe Strummer

  3. #48
    Nickname: Droid
    Join Date
    Jun 2005
    Location
    Green Bay, WI
    Posts
    2,352
    The FD current to the Hex/Cam-heads has two bearings in it; the large roller bearing that carries most all the wheel load. It runs in the FD fluid 100%, and the smaller ball bearing, which runs in its own grease supply packed into the bearing. When BMW changed the fluid volume in the FD it only affects the large roller bearing, the smaller ball bearing never contacts the oil volume.

    On the earlier FD common to my 07RT, the is no external wiper seal for the ball bearing with the grease in it. Jim at Nick's BMW says that contamination, water and debris, that gets into the ball bearing can displace the grease, which leads to the ball bearing failure. Also, aggressive cleaning with a pressure washer in the wheel area can cause water/detergent to get into the bearing. Later models have a wiper seal outside of the greased bearing to keep out water/contaminants. That seal can be added to earlier models.

    So, this winter the FD comes off my 07RT to get the seal installed.

  4. #49
    Cam Killer marchyman's Avatar
    Join Date
    Jun 2008
    Location
    SF Bay Area
    Posts
    3,442
    Quote Originally Posted by ANDYVH View Post
    The FD current to the Hex/Cam-heads has two bearings in it; the large roller bearing that carries most all the wheel load. It runs in the FD fluid 100%, and the smaller ball bearing, which runs in its own grease supply packed into the bearing. When BMW changed the fluid volume in the FD it only affects the large roller bearing, the smaller ball bearing never contacts the oil volume.


    Four bearings.

    1) Large ball bearing on crown gear that is NOT in the oil bath (wheel side bearing)
    2) Needle bearing that is in the oil bath (out side bearing)
    3) Pinion ball bearing
    4) Pinion needle bearing

    I *think* The bearing that fails most often these days is the large ball bearing... the one that is NOT in the oil bath. Number 7 in this diagram. Number 9 is the seal.

    245.png

  5. #50
    Nickname: Droid
    Join Date
    Jun 2005
    Location
    Green Bay, WI
    Posts
    2,352
    Yes, when you include the pinion bearings there are four in total. The one at issue though is the ball bearing that does not run in the fluid contained in the FD.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •