Sealed swing arm bearings?

[motodan]

Did BMW put sealed bearings in the swing arm on '88 - '93 R's?

 

[88bmwjeff]

Yes, to the best of my knowledge. My 88 R100 RT has sealed bearings. The bearings for the front wheel are also sealed.

 

[stevenrankin]

I was just looking

Someone just asked me about this and I did some looking. According to Max's microfiche the bearings are sealed for the swing arms after a certain date. What I found interesting is they say after 81? I could see a change in 85 perhaps when the mono lever bikes were introduced.

At the same time, I can also see them selling the bearings as a replacement for the OM bearings that required grease. While the fiche does not go into greater detail, it looks like the bearings may be interchangeable with the 81 and newer bikes.

So, not much of an answer, sorry. St.

 

[RPGR90s]

Bearings

Did BMW put sealed bearings in the swing arm on '88 - '93 R's?

My '93 RT had the same bearings as my R90s.

Pop the caps off the swingarm access. If there's a small hole, then use a tip insert on your grease gun to shoot some in.

Good time to check your swingarm clearances (frame to swingarm should be equal on both sides), as well as loosen and re-do the torque on the bearings. (Pre-load to 15 ft. lbs. Loosen and set to 7-9 ft. lbs.)

RPGR90s

 

[88bmwjeff]

My '93 RT had the same bearings as my R90s.

Pop the caps off the swingarm access. If there's a small hole, then use a tip insert on your grease gun to shoot some in.

Good time to check your swingarm clearances (frame to swingarm should be equal on both sides), as well as loosen and re-do the torque on the bearings. (Pre-load to 15 ft. lbs. Loosen and set to 7-9 ft. lbs.)

RPGR90s

The parts fiche indicate two separate part numbers for swing arm bearings for an R90S and a 1993 R100 RT. Also, the parts fiche from MAX BMW indicates sealed bearings since 1/1981. It appears that the bearings may have been replaced with non sealed versions on your '93 RT. The swing arm pivot pins on my bike (an 1988 R100 RT) still have the hole in the middle. Although the holes still exist, I don't see the purpose of shooting some grease in there, since none of the grease will make it to the bearings. It will only deposit grease in the inside of the swing arm making a mess, IMO.

 

[stevenrankin]

extra grease

LOL, yeah, the sealed bearings won't get grease in them using the supplied hole, but, the extra grease pumped in all around them in the swing arm might just keep out water and stuff that could get into them. Paper towels will wipe away any excess on the outside. Mind you, this is NOT a BMW tip. St.

 

[motodan]

What a conundrum, I'm pretty sure RPGR90s had his '93 since new and did all the wrenching on it. And 88bmwjeff brings out a number of probable reasons why he believes the swing arm bearings are sealed on my '93 RS and not repackable as with older models. So what's a guy to do? Here's a couple of early morning pictures, both left and right on where I plan to inject some moly to see what happens...just as soon as I buy the grease gun and Moly. However, first things first, so off for chemo then back to the priority of the day "problem". Thanks for all the input, this new to me bike has been great as it takes up time in a fun and sometimes mysterious way. See pictures in next post...

 

[motodan]

and here's the pictures (apparently I'm preoccupied).

 

[stevenrankin]

Lack

The lack of grease in the photos leads me to hazard a guess your bearings are sealed ones. Pumping more grease in is a waste really other than to surround the unit with grease on the outside and leak.

Is there a problem with the swing arm, I guess I should have asked a long time ago? There really isn't much that can go wrong with the bearings as they don't spin at all. Wear over a long period of time is mainly due to hammering as happens in the steering head bearings.

So, unless you have a wobble, or it is sticking or something really serious, I think you don't have to worry about greasing it for a long time. St.

 

[52184]

Sealed bearings were used for sure with the advent of the Paralever swingarm and it’s dry driveshaft tunnel. Also introduced at that time was the practice of venting the swingarm tunnel through the right-hand swingarm pivot pin. A backing plate is present behind the sealed bearing, closing it off from the dry swingarm tunnel save for a small hole through which the swingarm vents. So while on a Paralever-equipped bike it is possible to pump grease through the pivot pin, all that is accomplished is to fill the swingarm tunnel with grease and plug the vent path for the swing arm. The wet-driveshaft bikes vented their swingarms through a small notch above the seal on the output shaft, which is one reason why/how gear lube could be passed from one to the other if the vent through the speedo cable retaining bolt became blocked. That notch is sealed on the paralever bikes and the speedo cable bolt vents only the transmission.

So goes my recollection and understanding of the issue, based upon info from Clymer, Snowbum’s site, and personal experience removing some very greasy swingarms and driveshafts from paralever bikes at Tech Days. But, I’ve not had morning coffee yet…

Best,
DeVern

 

[RPGR90s]

What a conundrum, I'm pretty sure RPGR90s had his '93 since new and did all the wrenching on it. And 88bmwjeff brings out a number of probable reasons why he believes the swing arm bearings are sealed on my '93 RS and not repackable as with older models. So what's a guy to do? Here's a couple of early morning pictures, both left and right on where I plan to inject some moly to see what happens...just as soon as I buy the grease gun and Moly. However, first things first, so off for chemo then back to the priority of the day "problem". Thanks for all the input, this new to me bike has been great as it takes up time in a fun and sometimes mysterious way. See pictures in next post...

Right you are Dan, I bought it new.

Although I admit I never removed the swing-arm on the '93, I did pump in grease at least annually. And if memory serves, the grease coming out between the frame/swing-arm was old and different color from what I was pumping in.

I did replace the SA bearings on my R90s when I restored it back in '91 and those are definitely tapered style (non-sealed bearings), requiring grease.

A question for the group then. If Dan's bearings are sealed, would the tightening sequence of the adjustable pins and subsequent torque be a different process?

If I didn't want to pull the swing-arm apart to find out, why not use a grease gun with white or green or red grease. If the same color grease comes out of the swing-arm/frame gaps, would that prove that the bearings are sealed? Seems like a simple test.

RPGR90s

 

[motodan]

I will pump and report.

 

[motodan]

Is moly required or will moly do? Supposed if sealed it won’t matter.

 

[motodan]

Now pumped and reporting. Small left glob is what I put into the swing arm lube opening, larger right glob is what came out. What say you now? Take it the bearings aren’t sealed and this is old grease off of them OR they are sealed and someone over the last 29 annual services, at one time or another shot grease in there before and I just pushed that grease out…not actually touching any inner bearing surface?

 

[RPGR90s]

Is moly required or will moly do? Supposed if sealed it won’t matter.

if sealed, doesn't matter.

FWIW, I inspected the swing arm bearings on my '04 R1150RT over the winter as part of a series of items I was inspecting.

Those bearings are sealed so I removed the seals and was surprised to see the grease looked like brand new.

Sealed bearings seem to last a lifetime, so I wouldn't worry about it too much.