Snap Ring for 1987 K75S Drive Shaft Boot

I am replacing the drive shaft on my son's 1987 K75S and I am going with a brand new one from the factory. That order was placed and is expected to arrive in few weeks. I also ordered the protection boot (BMW part # 33 17 1454522), and that part, to my surprise, was IN STOCK at my local dealer in Canada. I also ordered the drive shaft snap ring (BMW part # 33 17 1450836) and was told it is no longer available and has not been replaced by any other part. It seems odd that the drive shaft and drive shaft protection boot were readily available, but not the snap ring. Any advice on where I should turn? Thanks all.

jimwil87 said:

I am replacing the drive shaft on my son's 1987 K75S and I am going with a brand new one from the factory. That order was placed and is expected to arrive in few weeks. I also ordered the protection boot (BMW part # 33 17 1454522), and that part, to my surprise, was IN STOCK at my local dealer in Canada. I also ordered the drive shaft snap ring (BMW part # 33 17 1450836) and was told it is no longer available and has not been replaced by any other part. It seems odd that the drive shaft and drive shaft protection boot were readily available, but not the snap ring. Any advice on where I should turn? Thanks all.

Click to expand...

Use the snap ring out of the old drive shaft. It is pretty easy to remove with an awl or machinist's scribe.

The snap ring that Jim is reffering to is the one that holds the boot on to the swing arm. I would just use the old one off the bike. There is no force on it. It doesn't go bad.

Max BMW parts fische still shows it as an available part. If I remember, I'll check with my dealer tomorrow to see if there are any in the states (if ther're open on Christmas Eve).

There are snap rings in this area.

I can only assume the K75 & K100 driveshafts are similar and the rubber boot on a K100 drive shaft is held on by a small snap ring on the inside of the rubber portion that fits inside the drive shaft tube. When installing the swing arm you have to make sure it is in place on the drive shaft tube and then you merely push the other end of the boot onto the flange at the transmission. Make sure you keep the tube fairly level and support the other end with a jack stand, wood or whatever you have handy. You then need to check with fingers/ mirror etc to make sure that the boot is attached to the transmission. Gently pull back on the swing arm assembly to see if it stays in place. Once it is in place, install the pivot pins ( keeping the swing arm/driveshaft fairly straight and supported ). Once you get the rear drive and the shock on you can remove the support. Put some grease onto the inside of the rubber boot portion that goes over the flange or put some on the flange, helps in getting the boot on and also seals out any moisture etc.

The other clip fits on the drive shaft end that goes onto the splines on the transmission. It normally should stay in its spot when you remove the driveshaft. Have the drive shaft fairly straight when you got to install it and gently push it up the tube. You may have to rotate the drive shaft a little bit to get it to line up with the splines. Put the transmission in gear. Then push it on until you hear a click. Gently pull back on the driveshaft to make sure it is in place. If the driveshaft stays in place and doesn't pull back you have it in place.

That explains the snap rings and as long as they are not broken they can be reused. I just went through this process on my K100 as I had to replace the engines rear main seal, so it is fresh in my mind.

Thanks gang. There was actually no snap ring inside the boot to re-use. The microfiche sites I looked at, including Bob's BMW, had the dreaded "AE" next to the part #. If any of you can track one down and point me in that direction, I would be most appreciative.

If you are unable to source a used snap ring you may be able to find a suitable substitute at McMaster-Carr.
https://www.mcmaster.com/snap-rings

Best,
DeVern

jimwil87 said:

Thanks gang. There was actually no snap ring inside the boot to re-use. The microfiche sites I looked at, including Bob's BMW, had the dreaded "AE" next to the part #. If any of you can track one down and point me in that direction, I would be most appreciative.

Click to expand...

If the swing arm was never out of the bike, I'm surprised that the snap ring you speak of is missing. You have to look really close at the old rubber boot as it just sits in a grove in the rubber. Really hard to see. It is really just a narrow piece of spring steel with hooks on the ends of the wire. Can be a bit fussy to get back in.

That portion of the swing arm doesn't move back and forth, just up and down slightly, so you might be able to get away with out it. If not measure the diameter and see if you can order just a snap ring from some other auto/bearing shop. As long as it is narrow and will fit in that groove it should work, as long as it doesn't interfer with the drive shaft. Any snap ring with similar dimensions could be made to work.

It is not really a normal snap ring. It is just a wire with the ends bent. But it is made of spring steel. It is something that could be overlooked because it sits deep in the groove in the boot.