Boxerworks.com

I'm on my way to fixing my tranny, and have discovered the need to replace my swing arm bearings. They are 31 y.o.

The swing arm bearings are similar to 30203 which is our wheel bearings. The difference being that the swing arm bearings have a dust/dirt cover on them.

The part number on the swing arm bearings is FAG 540619
From my research so far, this is a special bearing produced for bmw and is unobtanium, other than from a dealer.

The bike is an 81 RS.

Has anyone found an acceptable alternative?

Bearing cross reference table here:

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

Kurt in S.A.

Kurt in S.A. wrote:Bearing cross reference table here:

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

Kurt in S.A.

33 17 1 242 618 Swingarm bearing 1/81 thru K11 40x17x17 tapered roller FAG 540619 NF 32203?

Just use the 30203 plain cheapy bearing. I don't know your model, as it is too new for me, but isn't that side of the bearing covered by the seal?

Thanks for the replies chaps. The 30203 apparently will work. I don't know if there are any other changes to the 81 swing arm that necessitate the use of the sealed bearing.
Snowbum prefers to not use the seals due to the difficulty of greasing the bearings prior? to use. Apparently with the seal removed, or the use of 30203, allow for the bearings to be periodically greased via the hollow swing arm pivot bolt.
The outer race on the sealed bearings has a machined groove that accepts the actual plastic sealing ring.

What was used prior to the sealed bearings, just plain 30203 ?

I have never (to my memory) had my swing arm bearings out for servicing. I know I've tried but could not work out how to get them out. I know know, just apply a lever to the id of the bearing and they will come out.

Looks like the easiest way to get the outer race removed is by welding them out.

Use the 30203 with a heavy spacer/washer between
the trunnion pin and the bearing. Leaves a very small
amount of space around it to let any water and excess
grease out.
The FAG 32203 is difficult to obtain ( only made by FAG for BMW)
and about four times the price.

Yeah, weld them out. We used plain old 30203 for many years. The trick to a fair life is to grease them often with a single pump of new grease to shove out the old dirty grease. Takes a few seconds.

They must be adjusted correctly, or they fail quickly. You do not want much preload at all, just get the play out and you are done.

One would wish that when the swing arm is centered, so is the driveshaft. The driveshaft is more important than the swing arm to be centered. If they are different, that is a good sign that the bike was in a wreck.

A short mechanical surgery procedure and both outer races are 'outa there'
Welding them out really is a quick job. That would otherwise be another special tool requirement because the steering head bearing puller probably wouldn't fit.
Interestingly the outer race has a different number 539816 to the inner race 540619.

The swing arm bearing outer race width is 13mm compared to a 30203 dimension of 10.5 ~ 11mm so that is where a spacer will be needed to make up the difference.
I don't want to wait for the bearings to come from the UK, and I don't want to pay $100 a piece in Aus.

Time to put the thinking cap on.