Rear Wheel Bearing seems dusty

[Armo]

Well not so much dusty as its tuned to dust.

I cant quite figure out whats wrong with it, but i know this isnt right. hmmmmmm


The other day I rode to the bank and as I was pulling out i heard a clunk noise. So i stopped and did a visual check to see if I could find anything. I didnt find anything so I took it easy on the bike with no real issues.

So this morning me and my girl, my mom and old man are taking a trip to Williamsburg VA and we get about 2 miles down the road and I can hear what sounds like the rotor scraping against the brake pads. I'm looking down to see if i can see anything thats awry and thats when the rear tire swings out like i was riding in sand. That certainly go my attention, and when i pulled off to a park i looked at the read tire and there is transmission fluid leaking onto the back rim. so I'm thinking something realllly bad has happened.

we got it packed up in the back of a pickup and got it home and took the tire off. I could see a small strip of metal poking out of the rubber seal. When we pulled it out the transmission fluid was rolling out of it. We pull the drain plug and metal play-doh is caked on the magnet. so we pulled the seals and cover and shards and pieces of metal start falling out. take a look at the bearing and it looks like this:



we get both sets of bearings puled off of the rear.. tire rotor? is that what its called? and we are gonna get those replaced. all of the internal gears seem to be perfectly fine.




so if anyone has seen the rest of the ball bearings please let me know, no one has called yet when i put "Missing" posters up

my bike looks so sad =(

[towerworker]

What you have is a "Final Drive Failure" of which you can find many posts and threads. This is not something I would attempt to repair on your own unless you have all the appropriate presses and shims and knowledge of bearing "pre-load". You can certainly remove the FD and take it to an appropriate BMW repair shop and save some money that way. This is becoming a fairly common failure.

Wayne

[Armo]

do you suppose it could have been casued my the oil i was using in the FD? Mobil 1 synthetic 75w-140

i'm sure there is a machine shop near us that can press the new bearings onto the unit.

[Boxer]

OMG!

Jordan! What have you done? You should just set it back on the truck and haul it to the dealer. But if you are so inclined and/or have a friend who is also mechanically adept, you can remove the final drive as Towerworker said and let the dealer do what he needs to do then put the repaired FD back on yourself.

BEWARE! It is no easy task getting that FD off. Not REAL hard, but not easy either. You have to heat the area of the shaft housing near the pivot bolts to about 235 degrees to loosen the red loctite. Read the directions on the threads that Cyclerob has posted. He is very clear and concise about what should be done to take that off. While you're in there you will need to replace the pivot pin needle bearings as well. They go to crap faster than those front pivot pin bearings up at the front of the swing arm.

When you pull your drive shaft out, check the U-Joints for smoothness. If they are "notchy" at all I have one coming to me from Canada with only 20K miles on it that is yours for $200. I just bought it, including shipping, for $290 but decided not to use it after all.

[MikeCam]

Bearing race failures are part of a wear and tear cycle - not the same as a real Final Drive Failure (Wayne, you watch your tongue boy).

It seems they wear and tear at a rate faster than is the norm in many cases. It is unlikely anything you did, the oil you use, or the way you maintain your bike. Most likely is the cheap part sourced from a low quality provider was improperly shimmed and pre-loaded at the factory by under trained BMW unskilled labor. It was fated to happen from before you owned the bike. 3-5% of them will experience this fate. Sorry, but good on you for finding and seeing the problem.

[Boxer]

do you suppose it could have been casued my the oil i was using in the FD? Mobil 1 synthetic 75w-140

Not likely. The bearings have a "history" of failing.

i'm sure there is a machine shop near us that can press the new bearings onto the unit.

That's true. But that's just the easy part. It might work fine after doing that. But then again the inside bearing on the other side of the drive gear just might be bad as well. Wait and let Rob check in here on this. He knows of a way to check it without taking it all the way off, I'm sure. Your pivot pin bearings also probably are toast and need replacing as well. And since its that far apart you may as well pull the drive shaft and check it for slop. Just my humble opinion though. Wait for Rob's advice.

[Armo]

That's true. But that's just the easy part. It might work fine after doing that. But then again the inside bearing on the other side of the drive gear just might be bad as well. Wait and let Rob check in here on this. He knows of a way to check it without taking it all the way off, I'm sure. Your pivot pin bearings also probably are toast and need replacing as well. And since its that far apart you may as well pull the drive shaft and check it for slop. Just my humble opinion though. Wait for Rob's advice.

Yea We planned on replacing both bearing here:





as a CYA, I didnt see a reason not to replace both of them. We pulled them off with a bearing puller this morning but i'm still trying to get the smell of the FD oil off my hands. The thought of that stuff makes me start to gag.

cool thing is there dosnt appear to be ANY damage to the actual drive gears. they ust be made of some kind of indestructible alloy or something.

I'm just glad we were 2 miles from the house, and its only the bearings also remember my bike has mo warranty as the ... interesting way which I procured it. So its all up to me and the family to fix it. luckily we have just about every tool you can think of out there.

[bikermeow]

What's the part number on that? Will go look see mine

[Armo]

The ID markers on the small tapered bearing:

SKF 30205 J2/Q Germany-s 07 098y

The ID markers on the large bearing:

F A G 61917.C3 Germany 09V.B

[boxermania]

Armo
Don't panic, you are doing a great job, I see that you can get this back together easily.

Actually what you have experienced is "bearing cage failure" and that has been common to some of the oilheads, specially the earlier ones. I se them often in my line of work and is usually caused by a marginal bearing application for the usage. The part that is missing is the stamped and riveted portion that holds the balls in check, see around the 11 o'clock position (the last posting) and you will see a portion of the cage still intact.

You can source these bearings dirctly from any bearing supplier at a significant savings to you. One thing you might want to do is check with the dealer to see if there is a superceded replacement before you buy the replacements. I can't see the roller bearing surfaces (tapered bearing), but if it shows pits and yellowing replace as well, it's good practice. Clean everything well and put back together.

Here is a link to part numbers and bearing tags

http://www.largiader.com/parts/crossref.html

You will have to heat the bearing as Boxer indicates for installation, but that is easily done in the house oven. Just make sure that the shims behind the bearing go back in as they are the ones that set the backlash between the gears. Dino or synthetic oil are OK.....they are not the cause.

Keep us posted.....

[Armo]

Armo
Don't panic, you are doing a great job, I see that you can get this back together easily.

Actually what you have experienced is "bearing cage failure" and that has been common to some of the oilheads, specially the earlier ones. I se them often in my line of work and is usually caused by a marginal bearing application for the usage. The part that is missing is the stamped and riveted portion that holds the balls in check, see around the 11 o'clock position (the last posting) and you will see a portion of the cage still intact.

You can source these bearings dirctly from any bearing supplier at a significant savings to you. One thing you might want to do is check with the dealer to see if there is a superceded replacement before you buy the replacements. I can't see the roller bearing surfaces (tapered bearing), but if it shows pits and yellowing replace as well, it's good practice. Clean everything well and put back together.

Here is a link to part numbers and bearing tags

http://www.largiader.com/parts/crossref.html

You will have to heat the bearing as Boxer indicates for installation, but that is easily done in the house oven. Just make sure that the shims behind the bearing go back in as they are the ones that set the backlash between the gears. Dino or synthetic oil are OK.....they are not the cause.

Keep us posted.....

i was hoping the bearing supplier could mount the bearings on a press. should i do it myself instead of the supplier?

im good at taking things apart getting them back together without spare parts is another thing =P

[Boxer]

I don't know about the smaller bearing, but the big one just "fell" back in place when Rob and I heated it in the oven and then cooled the hub part in the freezer. Getting it OFF was the bear!
I would be concerned about the shimming. I think the existing shims are no longer the right size IF you replace both bearings.

[boxermania]

Bearings are manufactured to very precise tolerances and there is little difference between them. That being said, all you have to do is insure that the shims that came out with the bearing go back in. Your clearances will remain the same.

If you don't want to heat them up in an oven and install them yourself, the supplier will probably have a bearing heater (induction) and will install them for a small fee.

[jm1515]

Bearings are manufactured to very precise tolerances and there is little difference between them. That being said, all you have to do is insure that the shims that came out with the bearing go back in. Your clearances will remain the same..............

I cringe when I hear people say this.... Having just gone thru this, I say listen to Towerworker....
or better yet, listen to Anton himself....
http://www.bmwra.org/otl/finaldrive/
Go down ~1/2way, and read the part just above and below 'Shimming'.....
Essentially, if this is indeed a 'premature failure' on a low miles bike (How many miles Armo?), just re-using the same shim(s) can be a complete waste of time & money, since most of these failures, according to 2 of the most reliable & experienced sources out there, arise from improper shimming at the factory.
Armo...you're a better man than I. It seems you've taken this just a Iittle past simple crown bearing replacement. I was not prepared to properly do the math....Tom Cutter has my FD in 'good hands'.

[towerworker]

"Bearing race failures are part of a wear and tear cycle - not the same as a real Final Drive Failure (Wayne, you watch your tongue boy)."

Looks to me like a bearing race failure is still a failure. Either one puts the bike off the road and the final drive needs repair. An acceptable wear and tear cycle is 100K+ miles, not 30 to 40K.

My 93 Chevy S10 has 150K on it with absolutely no major failures of any kind. At this mileage I can expect it and would not be overly upset if it did. If the truck had 30 to 40k I would be upset and rightfully so.

Wayne

[sweatmark]

I'm with Wayne on this one: final drive bearing failure is Final Drive Failure. Nobody ever reports a problem with the crown/pinion gearset, just disintegration of the ball cage and rear drive seals.

Automotive differential "final drives" require similar shimming to properly load the hypoid gear, so - like the splined dry clutch used universally in car & truck applications - this problem with final drive failure at low miles is direct evidence of crappy design and poor manufacturing quality. This problem is not wear & tear.

Glad there's been an improvement in the big bearing spec. I'm putting a different gear ratio in my Rockster's final drive when its bearings/seals crap out. Can't wait for that happy day.

[Armo]

well we got the bearings on order. my dad got them from a bearing shop. the small tapered bearing was a reasonable cost, but the large one was not. the closest BMW shop was closed on Monday and he had ordered them from the shop before i could compare costs, but it seemed a bit strange that the large bearing was so expensive. Not to say that I know my bearings or anything. We did get the BMW brand from Germany/USA. The bearing shop said that for 1/2 the cost we could have gotten a Chinese or Japanese manufactured but the quality wouldn't be the same as the German/USA version that we got.

I don't really want to come out and say how much it was, but if anyone has replaced that bearing how much did they pay?

[Boxer]

I paid $107 dollars with the ChiBMW discount back in September of 08. I see now they are down to $75 at MAX BMW parts fiche.

[Armo]

I paid $107 dollars with the ChiBMW discount back in September of 08. I see now they are down to $75 at MAX BMW parts fiche.

yea, the old man paid a lot more... a lot more, than that before i could stop him. but oh well, as long as I can get it back together =)

i wanted to ask you how long, and how hot was the oven you guys used to heat the bearings up for to slide it on.

worst case scenario we have an acetylene torch that will sure as heck do the trick, but the oven may be healthier for the bike, lol.

[boxermania]

A typical kitchen oven wil suffice at 280 F.....I would stay away from the torch unless you and your dad, know what you are doing, no offense intended. The localized high heat of the torch can affect the bearing temper and the bearing might become twice as expensive......best of luck.

I would also stay away from the chinese bearings, for the time being......SKF, Timken would be some of my choices.