Final drive failure

[hops]

Had a bit of fun today trying to sort out my final drive output bearing. I didn't get any notice of impending doom then felt a bit of a rumble. When I took the rear wheel off the oil seal had been displaced.

Removal of the seal revealed the cause. The bearing had disintegrated

Had a bit of a problem getting the old bearing off as my pullers would not fit under the bearing as it was too close to the crown gear. So, the old remedy, large hammer and chisel to lift it slightly then wedge a chisel either side and lever against them.

Off it came, quite easily in the end. So bits in the freezer and others in the oven, hopefully a happy ending is nigh. Follow steppers advise and check yours soon!

The old and the new:-

 

[MattW]

Nice job

 

[dancata]

Q: my FD oil level is to the max (therefore ok, not loseing any) and if I take the rear wheel down everything is dry in there but if bike in neutral and i spin the rear wheel by hand, i can hear some bearing balls noise, shoul i open it and inspect or is it ok for that noise to be there?

Thanks,
Dan.

 

[hops]

I would

Pop the seal and have a look. You will need to replace the seal but it's a job worth doing in my opinion. If you do you are looking for any slight cracks in the bearing cage or missing rivets. There are other posts which show what to look for if you're still unsure.

 

[Fanum]

Q: my FD oil level is to the max (therefore ok, not loseing any) and if I take the rear wheel down everything is dry in there but if bike in neutral and i spin the rear wheel by hand, i can hear some bearing balls noise, shoul i open it and inspect or is it ok for that noise to be there?

Thanks,
Dan.

If it's got to the stage where the bearings are actually making that sort of noise, you would expect to at least be able to feel some play in the wheel

Grab it and give it a wiggle
If no movement, you could be mistaking the UJ noise for bearings?

 

[Steptoe]

If it's got to the stage where the bearings are actually making that sort of noise, you would expect to at least be able to feel some play in the wheel

Not necessarily. I've seen some spectacular bearing failures with no play at all at the wheel.

 

[dancata]

Not necessarily. I've seen some spectacular bearing failures with no play at all at the wheel.

my play is the wheel together with the FD, so the play is where the FD meets the shaft drive; for this, only adjustment is necessarly, right?

Thanks,
Dan.

 

[MattW]

my play is the wheel together with the FD, so the play is where the FD meets the shaft drive; for this, only adjustment is necessarly, right?

Thanks,
Dan.

Adjustment might fix it or you might need new paralever beaings

 

[hops]

even in that mess

Not necessarily. I've seen some spectacular bearing failures with no play at all at the wheel.

there was no sign of free-play on mine.

 

[JohnnyBoxer]

Had a bit of fun today trying to sort out my final drive output bearing. I didn't get any notice of impending doom then felt a bit of a rumble. When I took the rear wheel off the oil seal had been displaced.

Removal of the seal revealed the cause. The bearing had disintegrated

Had a bit of a problem getting the old bearing off as my pullers would not fit under the bearing as it was too close to the crown gear. So, the old remedy, large hammer and chisel to lift it slightly then wedge a chisel either side and lever against them.

Off it came, quite easily in the end. So bits in the freezer and others in the oven, hopefully a happy ending is nigh. Follow steppers advise and check yours soon!

The old and the new:-

How many miles??

 

[dancata]

Hi all,

I was thinking of a FD inspection this weekend, while the bike is appart, and the local bearing dealer told me he only has this:

Seals:
CR 85X110X10 CRW1 R (metalic) : 6.47 EUR

CR 85X110X12 HMSA10 RG (rubber) : 5.21 EUR

Ball bearing : 85x120x18


Can i go for the rubber seal? even if it's 2 mm more?

Thanks,
Dan.

 

[MattW]

Hi all,

I was thinking of a FD inspection this weekend, while the bike is appart, and the local bearing dealer told me he only has this:

Seals:
CR 85X110X10 CRW1 R (metalic) : 6.47 EUR

CR 85X110X12 HMSA10 RG (rubber) : 5.21 EUR

Ball bearing : 85x120x18


Can i go for the rubber seal? even if it's 2 mm more?

Thanks,
Dan.

This is crazy - buy the BMW seal, it's not expensive and will fit correctly. Trying to force in a larger seal is just asking for trouble.

Same with the bearing - the BMW part is often cheaper than the standard bearing supplier part. If you do get a standard bearing, make sure that it's the correct tolerance class (C3 from memory but you'll need to check this).

 

[Steptoe]

This is crazy - buy the BMW seal, it's not expensive and will fit correctly. Trying to force in a larger seal is just asking for trouble.

.

I'm beginning to think that Mr dancata is a wind up/troll.

 

[MattW]

I'm beginning to think that Mr dancata is a wind up/troll.

I know - I'm thinking the same

In fact I almost hope that he is...

 

[dancata]

I'm beginning to think that Mr dancata is a wind up/troll.

I admire your patience of explaining people technical stuff on Gs's and writeing articles, but...

Since the cheapest thing in a bmw is the rider and 6 bolts from the clutch housing represent 7% of my monthly salary, i'm always thinking of cheaper solutions.

I just asked if i could use another seal, if yes then ok, if not, then i will buy the bmw one.

I don't want to be considered a troll or a prank, and would like to be answered when i ask questions, as well as i will answer to others when they ask.



Thanks,
Dan

 

[dancata]

What is it that i do that you consider me a troll? so i will avoid in the future.

 

[MattW]

I admire your patience of explaining people technical stuff on Gs's and writeing articles, but...

Since the cheapest thing in a bmw is the rider and 6 bolts from the clutch housing represent 7% of my monthly salary, i'm always thinking of cheaper solutions.

I just asked if i could use another seal, if yes then ok, if not, then i will buy the bmw one.

I don't want to be considered a troll or a prank, and would like to be answered when i ask questions, as well as i will answer to others when they ask.



Thanks,
Dan

Fair enough Dan - I apologise if I thought perhaps you were a troll - you must appreciate that some people take pleasure in causing trouble in forums and it's sometimes difficult to sort genuine questions from 'jokes'!

We all seek ways to economise when running our bikes (or most of us do anyway - perhaps not 1200 riders ). However, although you can substitute some manufacturer parts for standard 'off the shelf' parts, there are some things where its just not practical or possible - the 'one time' clutch bolts and certain seals etc being two recent cases in point.

You must realise that people like Steptoe have been answering questions on here for years and probably get slightly frustrated at times but keep asking the questions and I will do my best to help (as I'm sure will others).

 

[Steptoe]

Can i go for the rubber seal? even if it's 2 mm more?

Thanks,
Dan.

I just asked if i could use another seal, if yes then ok, if not, then i will buy the bmw one.

I don't want to be considered a troll or a prank, and would like to be answered when i ask questions, as well as i will answer to others when they ask.

Dan, i doubt anyone has ever tried the seal you asked about - Why don't you try it, and then you can tell us if it works so we can all save money if we need this seal in the future.

 

[MattW]

Dan,
I've done some digging and found the dimensions and specifications of the seal you are looking at (attached below). However I can't find the dimensions of the BMW part - perhaps you can, or someone else may have the information so that you can compare?

 

[dancata]

Dan,
I've done some digging and found the dimensions and specifications of the seal you are looking at (attached below). However I can't find the dimensions of the BMW part - perhaps you can, or someone else may have the information so that you can compare?

the skf seal is 12mm thick and the oem one is 10; i'll go for the bmw10 mm seal .

only asked because i thought mounting the 12mm one would fit in there;

but as i appreciate your and steptoe's technical skills, i will go for the 10mm one, since it is vital for my safety and the bike's