I just finished searching the forum looking for reasons for my handle bars oscillating (mainly on right hand sweepers above 100kmh), and came across a thread by MikeP on replacing the crown wheel bearing and seal. My back wheel has a couple of mm of play with my hands held at 6-12 and 3-9. Since I have already replaced the steering head bearings, front wheel bearings, swing arm bearings, tyres, wheel balance, springs and rear shock, surely this MUST be the thing that is causing the wobble??????? The other question i have is what else could cause the back wheel (definitely not the swing arm, just the wheel) to wobble?

Paralever final drive? Prolly the two pivot bearings. This is common on those FDs. Of course, if it's a standard Monolever, it could also be the large bearing inside the FD. With that much play it's gunna get scary really fast. Listen for a grinding or low hum as you rotate the wheel. Drain the gear oil and look for bits.

If the four wheel bolts are tightened up and the spacer is missing will they bottom out, leaving some play?

TacKler wrote:If the four wheel bolts are tightened up and the spacer is missing will they bottom out, leaving some play?

good point dave


good luck marc

There is no grinding/droning sounds (just what you would expect from the meshing/unmeshing of the FD) but I will drop the oil on the morro and further investigate. Its a monolever TWB.

I remember installing the spacer before the wheel so its not that. I am starting to feel a little more positive now. I have owned a couple of shaft drives but never had the need to delve into them. Will a local bearing shop have the parts and O ring or is it a mail order job for the geographicaly challenged like myself?

they may have the oring , the big bearing unlikely ...but orderable ...perhaps

the oring from the local suppliers  produces this   oring 171.12 x 2.6    part=  bs166n70 from cbc suppliers  $6.67 +gst

I found a suitable bevel bearing from somewhere  under $25 from memory

but the big bearing ??  haven't  done that search yet   you may find the dimensions on the real oem suppliers parts lists  - 85X120X18

motobins at 38 pounds ...motorworks at 40  pounds




good luck marc

Yeah, the thickness of the shim has little/no bearing on the lug bolt's ability to be tightened fully. My Big Block has no shim 'tween wheel and FD surface.

I've never seen an aftermarket bearing supplier making that bearing available. Fraid it's dealer only.

Unless you need to be riding soon I'd say 'Bins or 'Works are your best bets.

My K100RT needed the final drive to be sorted too. I had a suspicion and got it checked out, the big bearing was the problem and this was before it was showing any play at all. The trick is to get to it the minute you have doubts, if you leave it the rest can become toast fairly quickly. The big bearing is the same one across a lot of the BMW final drives. A habit I have is I always check temperature of final drive and wheel bearings after a trip. If you ever tow a trailer its a habit you get, checking trailer wheel bearings and its no different. Wear means more friction means more heat and possible play.

The OEM crown wheel bearing comes from SKF and was quite a lot cheaper when bought from BMW, I found. Mine is currently running a NTN 6197C3 which is a 17 ball bearing (later OE ones are 19 ball) but whatever.

If it is actually the crown wheel bearing (i.e. the big single wheel bearing for the rear) it'd be pretty scary at 2mm play, I bet mine was at about 0.5mm the bike leapt about after hitting road imperfections - I nursed it home knowing full well something had gone wrong somewhere. What's the mileage of the bike, these bearings seem to give in around the 70-80K mile mark..

Snod Blatter wrote:The OEM crown wheel bearing comes from SKF and was quite a lot cheaper when bought from BMW, I found. Mine is currently running a NTN 6197C3 which is a 17 ball bearing (later OE ones are 19 ball) but whatever.

If it is actually the crown wheel bearing (i.e. the big single wheel bearing for the rear) it'd be pretty scary at 2mm play, I bet mine was at about 0.5mm the bike leapt about after hitting road imperfections - I nursed it home knowing full well something had gone wrong somewhere. What's the mileage of the bike, these bearings seem to give in around the 70-80K mile mark..

That's exactly where mine went!

my odometer stopped working at 193000km or so. I have no idea how long ago that was, it's also the second speedo so mileage is pretty well open for guesses.

Which seal do I need to order from 'Bins? There are two and I am betting its the larger (more expensive) seal. The small one (input) is Code: 43115 the larger (output) is Code: 43220

yeah the input seal is quite small by comparison (but often overlooked , leaking oil into the driveshaft splines and washing off the lubricant )

the big one is the go

don't forget to run around the hub of the output shaft with some wet and dry , to take the small lip in the metalworks ….before installing the shaft through the seal ….and lots of trani oil to grease it up as it goes over the shaft

good luck mate

Thanks Charlie