Final Drive - Bearing Replacement

[NEOhioRider]

Long time member, but I only post once in a while.

My bike: 2000 R1100s. Purchased in 2009 with 16,000 miles on her. Currently at 50,300 (I know - not too many miles in 6 years, but winters are long here up by Lake Erie...I ride as I can). Over the years, I have done all the scheduled maintenance myself pretty much by the book schedule, changed my own tires, and also replaced the final drive pivot bearings at 39,000 (there was a horrible squeak coming from the rear end and folks on this board helped my diagnose it). That job is holding up fine after 11,000 miles.

This board has been fantastic over the years, just to better understand the R1100s and various tips and tricks to keep it running (and more importantly, what to look for and what to ignore), so I figured I would tell my latest story. I may be short on technical details, but every story helps.

So, a few weeks ago, I go out to the garage and find a puddle of "water" underneath my rear wheel. I did put the bike away wet the night before (giant storm in NE Ohio I rode home in), but that seemed odd. Oops - almost slipped in the puddle of "water." Crud - it's gear oil.

Trace the source, it is coming from the hub. I figure it is the main seal. Get the wheel off. Yep, there is the leak at the seal. I know at this point that I either have just a failed seal or a bearing failure (leading to the seal failure). Dump the gear oil. Lots of shiny bits. Ugh.

It had happened, I was one of those guys with an R1100 with a busted final drive.

Side note, I had noticed during the last washing that the rear wheel was notchy and even a bit crunchy when I spun it. I knew something was up. I put it into the back of my head. I should have done something then. Listen to your bike.

No need to panic. Open up the the Clymers and Haynes manuals, and hit the Internet to learn up.

Long story short, the main ball bearing was shot to hell. It came apart and ate the seal. Everything else seemed OK. No damage that I could find. I did the job right and replaced the main seal, the ball bearing, the cover gasket, the taper bearing, the shim, the thrust washer and the taper bearing race. The taper bearing looked fine, but I succumbed to "while I'm in here" reasoning and replaced it as part of this job.

Total cost of parts was $217.52. Here is what I bought from Max BMW

1/33121242211 |GROOVED BALL BEARING - 85X120X18 |$106.26|
1/33127663482 |SHAFT SEAL - 85X110X10 | $34.47|
1/33121450481 |TAPERED ROLLER BEARING - 25X52X16,25 | $48.76|
1/33111241257 |O-RING - 171,1X2,62 | $7.61|
1/33121450086 |SHIM - 2,400MM | $7.38|
1/33122310551 |SHIM - 0,700MM | $13.04|

Side note, the tapered roller bearing can be purchased for about 20 dollars. I learned this later. It is simply an SKF BR30205. the SKF is not an "aftermarket" bearing, it is the bearing manufacturer used by BMW on my 2000 year bike. This is the identical part you will get from the dealer, and is the identical part I pulled from my bike, down to the stamping on the part. Save yourself a few bucks if you do this job. Just search for a new SKF BR30205 in the original box from a reputable seller. You can even buy 10 of them for $100 with free shipping if you think you need them. Ha. So, anyone know the manufacturer of the ball bearing? I bet the original parts can be had for less than $106. But I digress.

Anyway, to make a long story short, the job isn't that hard if you do other medium-difficulty jobs on the bike and assuming nothing went really wrong with your failure. Changing the fuel filter is more of a cuss fest. The hardest part was pulling off the old bearings. I have a press that worked fine for putting the new ones on. They went on like butter with a cold crown-gear and bit of heat to the bearings. Everything buttoned up nicely if you take your time and understand what you are doing. Again, pulling the bearings off was the hardest part - I got some basic inexpensive pullers from the auto parts store and had to go to work on them with my Dremel so they could have enough purchase on the smaller bike parts to actually work.

Is this harder than changing out a chain and sprockets? Yes, a bit more, but that job is also not that trivial and those parts cost money also (especially if you buy the good stuff!) I can't really complain too much about this failure at 50K. You don't need many tools. You need something to pull the bearings, something to press the new ones on, and a seal driver set (20 bucks), and then your regular stuff like a heat gun and wrenches, etc.

Some of you may be wondering about the shims and the pre-load. I did a lot of thinking about this. I determined that I simply did not have the tools to accurately measure whether or not my bike was shimmed correctly. So, I figured I would leave it alone. I bought a new shim of the original thickness because, hey, new parts! I figured any guesswork could be worse that what I have now, and hey, if she lasts 50K more between failures, I'm happy.

A few pictures showing the carnage and re-assembly. This is not a step-by-step, just some pictures for your amusement.

Here is the final drive housing. Not cleaned yet, but no damage to speak of. The gearing looks terrific (shiny spots you see are from the flash on my crummy cell phone camera). This got the royal cleaning treatment before assembly and was clean enough to eat off of.


Here is the ball bearing. Note the carnage, and the seal spring that had escaped from the main seal.


My $80 Harbor Freight bench top press. It worked fine for this job.


The crown gear, with the taper bearing on, pressed into the cover with the seal.


The hub showing through the seal, and the cover is ready to mount.


Crown gear assembly and cover mounted.


Back view.


Right side view, brake and sensors not yet attached.


A motorcycle, ready to go.


The bike rides much better. It is sort of like the new tire effect. You don't know how badly something has degraded because it goes bit by bit, but the ride is smoother and tighter. Everything seems fine (knock on wood). I rung her out pretty good on my test rides.

I'm a slow worker (my day job is demanding and I only have so much energy), and I work carefully. This took me a couple of weekends. If I had to do it again tomorrow, I could do it in 1 day easy.

These are great machines. With a little care, I hope to keep this one for a few more years. Up next, I have another dreaded fuel filter replacement (I hate that job) and the brake discs are worn past specification. Maybe late in the fall, or over the winter. I'll space the jobs out.

Tom

[brentw1]

I calculate the shim thickness by assembling without the shim and the new parts,
then use a dial gauge to measure the end play with the bearing pressed into the
fd and then pulled out with the lug nuts, the bearing will slide in the housing
and you will get a accurate shim thickness, or you can buy the army of tools from bmw and
measure and calculate it.

[908/930]

Has anybody else here changed the bearing prior to any problems? Any idea what is the expected lifespan? I just ordered bearings and seals from MotorworksUK, figured I would change the bearings prior to any failure with a couple longer distance rides planned.

[njsax]

Originally Posted by NEOhioRider

. . . These are great machines. With a little care, I hope to keep this one for a few more years. Up next, I have another dreaded fuel filter replacement (I hate that job) and the brake discs are worn past specification. Maybe late in the fall, or over the winter. I'll space the jobs out.

Tom

Nice report, Tom! Thanks for posting. I probably would have just gone to Ebay and bought a used unit like I did once for my old K1200RS. But now, maybe I'll go your route if the problem ever presents with my R1100S.

[908/930]

I probably should have said reviving an old post, from 2015. My thought about a used unit is they do have a life expectancy, so it could fail in 2000mi or go 100K mi, so how far from home when it does fail.

[jdazey]

I'm glad you did revive the post. Now that I've read the report, the job doesn't sound so intimidating, not that I want to do it you understand

[JimMoore]

Originally Posted by 908/930

I probably should have said reviving an old post, from 2015. My thought about a used unit is they do have a life expectancy, so it could fail in 2000mi or go 100K mi, so how far from home when it does fail.

This was a not-entirely-uncommon issue for a number of years. The ones that failed would fail like clockwork at 50K miles. The ones that didn't fail would go forever. Idk if I would dive into one that hadn't failed, especially if it was well past the 50K mark. Maybe throw it in the saddlebag as insurance on a long trip.

That being said, if I did have a bad one I'd be tempted to go down one size on the shim. The failure was thought to be related to being mis-shimmed at the factory.

[908/930]

I ordered the parts months ago decided to open it up, glad I did, when I removed the drain plug there was metal particles attached to the magnet. Once removed from the bike could feel that the input shaft was not rotating smooth, big bearing was on its way out. Once removed could see spalling on the outer raceway.

It does require a couple of tools to remove the bearings. After measuring crown gear shaft and inside diameter of big bearing decided to polish off about .0005" off the shaft, still about .001" press fit, should be more than enough for that bearing.

Bike has 135,000km (80k miles) on it.

[jdazey]

Wow, you caught it in time!