Greg's FD bearings deconstructed

[Nin]

I bought one of greg's FD bearings at the ridiculously cheap price of £29.99.

Since then some have raised concerns about whether the metal shielding might make it unsuitable for an oil rich lubrication.

So I thought I'd do a bit of investigation

Using the little pick I was able to lift the metal shielding

Which then just lifts out

And leaves a pretty conventional looking FD bearing.

I think I'd be happy to install that.

 

[beemer pimp]

I wouldn't worry about shielding , gearbox bearings have rubber seals so no difference, metal shield mostly used for bearings open to elements .

 

[beemer pimp]

Any more for sale ? Maybe link...

 

[West coast gser]

Hmmm .. Id pack that with some more grease by the look of it ..

 

[Greg Masters]

Any more for sale ? Maybe link...

Just PayPal me £29.99 and a bearing will be in the post!

 

[Paul G (BHT)]

Hmmm .. Id pack that with some more grease by the look of it ..

 

[Ian J Hartley]

Hmmm .. Id pack that with some more grease by the look of it ..

You're probably not aware that this bearing sits in a pool of gear oil in the final drive assembly. So it is lubricated by oil and not grease. Any grease packed into the bearing would just get washed out by the oil.

 

[Slipperyeel]

You're probably not aware that this bearing sits in a pool of gear oil in the final drive assembly. So it is lubricated by oil and not grease. Any grease packed into the bearing would just get washed out by the oil.

Just what I thought

And then I thought he might be pulling a few legs?

 

[Ian J Hartley]

Just what I thought

And then I thought he might be pulling a few legs?

I did think that at first, but then thought as its a technical section and a place of knowledge and learning, it would do no harm to set the record straight just in case.

Ian

 

[tonytobo]

I did think that at first, but then thought as its a technical section and a place of knowledge and learning, it would do no harm to set the record straight just in case.

Ian

 

[West coast gser]

You're probably not aware that this bearing sits in a pool of gear oil in the final drive assembly. So it is lubricated by oil and not grease. Any grease packed into the bearing would just get washed out by the oil.

Hi cheers wasnt aware of that ..being a GS newbie ..

 

[Thirsty 1]

Where is this bearing from??? I've replaced several and the only source is BMW???

 

[Steptoe]

Where is this bearing from??? I've replaced several and the only source is BMW???

Ridiculous, the bearing used on the BMW final drive is a standard size and can be obtained from any half decent bearing stockist.

 

[PhaedrusMC]

Ridiculous, the bearing used on the BMW final drive is a standard size and can be obtained from any half decent bearing stockist.

Isn't this the case for all/most bearings used in bikes & cars? Whatever BMW (or any brand) label "their" bearings as, they're likely supplied to them by an independent bearing manufacturer. And once a punter can ID the bearing they need, it's almost always possible and cheaper to go direct to a bearing supplier, no?

 

[The Grey One]

Isn't this the case for all/most bearings used in bikes & cars? Whatever BMW (or any brand) label "their" bearings as, they're likely supplied to them by an independent bearing manufacturer. And once a punter can ID the bearing they need, it's almost always possible and cheaper to go direct to a bearing supplier, no?

Yes, that is right as with a lot of components the "manufacturer " is in fact an assembler of parts bought in. It is almost always possible to source bearings from a bearing specialist that will be exactly the same as those originally fitted. Same applies to many other parts, those who say you must fit original manufactures are deluded I'm afraid. It does pay to check the OE price first though as I came across lots of examples where they were actually cheaper than alternatives.

John

 

[Steptoe]

Isn't this the case for all/most bearings used in bikes & cars? Whatever BMW (or any brand) label "their" bearings as, they're likely supplied to them by an independent bearing manufacturer. And once a punter can ID the bearing they need, it's almost always possible and cheaper to go direct to a bearing supplier, no?

Almost 100% correct

But BMW do use a couple of unique to BMW bearings.

 

[The Grey One]

Almost 100% correct

But BMW do use a couple of unique to BMW bearings.

He did say almost! When running my Citroen garage I found one type of bearing that I could not get anywhere but from Citroen-a gearbox bearing for a 4X4 Mehari, a vehicle that had never been officially imported into the UK. There will always be exceptions but for the vast majority of bearings your local supplier will be able to help.

John

 

[MikeO]

Where is this bearing from??? I've replaced several and the only source is BMW???

The bearing measurements are listed on their parts fiche...

 

[Kenny Rodkiss]

From simply bearings, from £40 up £123.
http://simplybearings.co.uk/shop/advanced_search_result.php?search_in_description=0&sort=2a&search_3fields=1&keywords1=85&keywords2=120&keywords3=18&osCsid=7d7898e28f72aa696f6a2c14a3a379e0

 

[Ian J Hartley]

The bearing fitted to the final drive is a:-
61917C3
Open type, Thin wall, Deep grooved, Ball type
(I/d 85mm X o/d 120mm X 18mm)

You can buy this bearing from any bearing supplier or independent motorcycle parts supplier. Prices may vary.

You can also buy:-
61917
or
61917NSE,
or
61917DU,RS,SH,RSR,LU,2NSE,DDU,2RS,2RSH,PP,RSR,LLU,ZZE,ZZ,2Z,KDD,DD,FF,2ZR......etc

If you want, you can buy any old bearing and stuff it it, open, metal shielded, rubber shielded, Who cares? Tolerances, what the fuck are they? why care! Stick it in and rock on! Your back wheel spins at roughly 1000rpm at 75mph. The bearing will get warm and expand. If it doesn't get adequate lubricated, because of shielding. Then it will just get a little warmer and expand a bit more. But hey what do you care right! A bearing is a bearing is a bearing. It was the right size often all.

My point being:-
You may think that because these bearings have the same dimension, they are all the same.

They are Not.

Buy the bearing of the correct type and spec and fit it correctly, and you will reduce your chances of failure.