Swing arm bearings

[professorfate]

Is the swing arm bearing an easily obtained standard bearing or totally BMW?
Thanks.
1983 R65

[Bob_Roller]

Here's a page from RealOEM .

http://www.realoem.com/bmw/enUS/showparts?id=0364-USA-09-1980-248-BMW-R65&diagId=33_0624

Item 6.

I think all you need is 40x17x14, to get a bearing .

[montmil]

Make a note of the bearing size and visit any bearing supply house. You'll usually find nice SKS bearings at very reasonable prices. Same goes for wheel bearings and seals.

I just bought a shift shaft oil seal for far less than from BMW. $5.21 IIRC.

[wilcom]

I was just reading something about those bearings and the seals. I went back and found it and pasted it below. might be some good info about the seals



http://bmwmotorcycletech.info/inputsplinesthrowout.htm


"The swing arm bearing is basically the same as the pre-1985 wheel bearing, a
 Â    common type from any bearing supply company.  I prefer to NOT use sealed versions of those bearings
 Â    (or, I remove the seal), allowing ME to better grease from the outside, after the bike is reassembled,
 Â    via the center Allen wrench hole in the threaded pin adjustor.  "

[professorfate]

Thanks, I got a timken 30203 from Carquest  which is about 1/8 narrower but a washer on it and the pivot pin will go in all the way.
Thanks!

Make a note of the bearing size and visit any bearing supply house. You'll usually find nice SKS bearings at very reasonable prices. Same goes for wheel bearings and seals.

I just bought a shift shaft oil seal for far less than from BMW. $5.21 IIRC.

[Tony Smith]

Is the swing arm bearing an easily obtained standard bearing or totally BMW?
Thanks.
1983 R65

As far as I know all the roller bearings and all of the seals in an airhead are "catalogue" rather than "special" parts - makes a change form Japanese engines.

I think that the swingiarm bearings are the same as the wheel bearings, but others will doubtless chime in.

Only trick with swing-arm bearings is the outer race. If you have a blind bearing/race removal tool, or own an arc welder, no problem. If not then you are going to need one or the other (I would go for the welder as it us useful for other things and will cost less than a quality blind bearing puller anyway).

There are some "special" tools made by one of the US airhead shops that include an outwardly clever tool to pull races from steering heads, wheels, swing-arm etc. Unfortunately it costs nearly as much as a Chinese stick welder and I have seen various reports that were less than favorable on how well it works.

Swing-arm bearings have a dog's life, they only turn the same minor percentage of a circle millions of times with the same points bearing the load. It could be argued that tapered rollers are a pretty stupid idea for swing-arm bearings and that a carefully reamed set of bronze bushes would do a far, far better job.

But the bearings last well enough and don't require an accurately ground swing-arm bolt and expensive reamers to fit, so I'll give BMW an uptick on this one.

[georgesgiralt]

Tony, you never owned an Yamaha XS650, otherwise you'll find the BMW swing arm bearing solution a perfect one !
Yamaha thought that a bronze bearing, without seal, was a good (mean cheap) idea. Alas, it lasted only 20 000 km max if perfectly sought after. Price was the same than a couple bearings from BMW (no catalogue parts here) and exchanging them was a pita plus the special tools. Once every three changes, you had to buy a new axle for the swing arm and that was very very costly...
Even with new bearings, the swing arm was not perfectly guided and the machine has a "swinging rear" as my friends told me ....

[Tony Smith]

Tony, you never owned an Yamaha XS650, otherwise you'll find the BMW swing arm bearing solution a perfect one !
Yamaha thought that a bronze bearing, without seal, was a good (mean cheap) idea. Alas, it lasted only 20 000 km max if perfectly sought after. Price was the same than a couple bearings from BMW (no catalogue parts here) and exchanging them was a pita plus the special tools. Once every three changes, you had to buy a new axle for the swing arm and that was very very costly...
Even with new bearings, the swing arm was not perfectly guided and the machine has a "swinging rear" as my friends told me ....

You are right, I've never had the doubtful pleasure of owning one of the best Japanese copies of a Triumph.

But I have many motorcycles that use bronze (or other material) bushes for swinging arms. The trick is to service them before they fail (funny that). if your swing-arm has movement with brand new bushes then either the arm, the axle/bolt or the bushes themselves are not correctly spec'd. I'd check the axle and if was OK, I'd make my own bushes to suit the rest.

I owned a Honda XL350 that ate bushes because the sizing was utterly inadequate, on three occasions I had to cut the axle in 4 places so that I could drive rthe axle and bushes out of the swing arm. If nothing else the process improved my ability to hacksaw accurately, the outer cuts had to go down the centre of the "lip" of the bushes and then through the axle, the inner cuts were through a pair of press in steel bushes in the central spine of the frame.

It used to take a while to cut through that blasted axle, Honda used good steel for such things....

[georgesgiralt]

Yes, you're right, if done properly, it will last. Alas, the Yamaha was far from it. The dorsal spine of the frame was just welded in two very small spots on the gussets. I wonder why they even managed to put some steel here ! So the swing arm was able to rotate around the spine of the frame. This accounted for a funny road handling and bizarre worn marks on the rear tire...
My friends named it "the helicopter". One hour flight, ten hours shop... Boy, they were right !
One of the most funny thing was that the points were on one side of the head, and the advance mechanism on the other side of the head. They were linked by a very thin axle passing through the camshaft. So the advance was changing with the torsion of this bar... A joy to set properly !
I'll stop here otherwise I would have nightmares !

[Ed Miller]

On my '81 the wheel bearings and swing arm bearings are the same, and the same Ed Korn tool works to remove the races.  Unlike Snowbum, if I could find sealed versions of both I would install them.

[Barry]

My swinging arm bearings are original. At 28 years old when the bike came to me the grease had gone so hard it was impossible to force new grease through. Once cleaned up the grease goes in relatively easy and comes out the gap between the frame and the swinging arm. I reckon with regular greasing they'll last for ever.  

I've had bikes with bushes and they didn't last. Lack of provision for greasing didn't help and the average owner (I was an average owner at the time) wasn't going to strip the thing down on a regular basis.

[montmil]

My swinging arm bearings are original. At 28 years old when the bike came to me the grease had gone so hard it was impossible to force new grease through. Once cleaned up the grease goes in relatively easy and comes out the gap between the frame and the swinging arm.

If you've ever wondered how much grease is enough for the swing arm bearings, Barry's casual comment answers that question.

You'll need a tapered rubber tip on your grease gun to do a mostly tidy job of injecting grease through the small hole in the pivot pins. FLAPS is a source or I found mine at Tractor Supply... It's Texas y'all.

[Tony Smith]

[

You'll need a tapered rubber tip on your grease gun to do a mostly tidy job of injecting grease through the small hole in the pivot pins. FLAPS is a source or I found mine at Tractor Supply... It's Texas y'all.

Motobins Part No.99810  GBP7.00