K1300 Wobbly rear wheel.

[armstrongracer]

Was riding to work this morning another biker taps me on the shoulder and says your back wheel has a very nasty wobble. Put it down to a wear pattern as tyre is well shot and squared off but feels ok apart from normal tramlining that squared Road 5's do. Just in case, I put bike on a stand and tried to find play. Sure enough could feel some play but wasnt sure if it was excessive. Put in gear and spun rear wheel up. Fairly shocking! Wheel is wobbling alarmingly, probably play in the drive box but could also be a bent wheel, I regularly do quck sunday runs over the Wicklow gap trying to keep up with mates V4 Tuono and V4 Streetfighter which is a bit of a rough road to be hussling a big old bus like the K1300s on.

https://flic.kr/p/2oXe5Ky

So looks like I've got a final drive rebuild on my hands. Pointers as to which bearings are likely to be gone and links to videos or guides greatly accepted.

[raesewell]

Before you go rebuilding things check the obvious. Is the wheel seated properly, are the wheel bolts tight?

[Swindon Andy]

Also an obvious is to have the wheel itself checked.

[GlynH]

And maybe double-check the rear wheel flange as that was subject to a recall at some point in the past although I don't think mine has ever been done.

-=Glyn=-

[armstrongracer]

Cheers I'll check out a few things before I go feral on the transaxle.

Mine is a late model 1300s motorsport with the forged wheels, I assume that the flange issue had been sorted by then.

edit:  Checked wheel bolts, thought it would be too easy a solution.  If anything they are too tight, I am a bit anal about torque wrench + loctite, and cant budge bolts in any direction. Will get an impact gun on bolts at the weekend and will inspect the assembly. There are not many good used transaxles on ebay, rebuild without BMW's special tools looks difficult.

[Grumpy jase]

When I removed my rear wheel for tyre change last week, wheel bolts were extremely tight / stuck.  I broke my T50? socket with an impact gun.  I would suggest, give them a good dousing with WD40 and then use a breaker bar as opposed to an impact gun.

[TomL]

Is there play in the rear wheel or is there a big run out at the rim. Two entirely different problems. It's not clear from your description.

[armstrongracer]

I can feel a couple of millimetres movement when I try to wiggle the wheel, however the runout when spinning in gear looks much worse than that. Could be an optical illusion with a spinning wheel. Ultimately I should not be able to feel the amount of play I'm getting.

[Matt]

Cheers I'll check out a few things before I go feral on the transaxle.

Mine is a late model 1300s motorsport with the forged wheels, I assume that the flange issue had been sorted by then.

edit:  Checked wheel bolts, thought it would be too easy a solution.  If anything they are too tight, I am a bit anal about torque wrench + loctite, and cant budge bolts in any direction. Will get an impact gun on bolts at the weekend and will inspect the assembly. There are not many good used transaxles on ebay, rebuild without BMW's special tools looks difficult.

That's scary! I had (and lots of us do) a Motorsport too, and it had to go in for that recall.

When getting tyres I'd always "helpfully remind" my tyre chap that they need to be at 65Nm or whatever it was. My KTM is 250Nm on the single thing. Proves a right pain in the bum to remove every time!

[armstrongracer]

Never heard about that recall, mine was a 2015my, did recall run that late.

Edit:  Did a search and came up with a recall note concerning various models including K1300s and r models for possible cracked wheel flanges. That particular recall was only up to 2011 models. Looks like the fix was a steel flange replacing an ally one + an ally spacer to make up thickness difference. Should be an easy check.

[richtea]

... the runout when spinning in gear looks much worse than that. Could be an optical illusion with a spinning wheel.

Put a stick/pointer against the wheel, spin it again, and see how far it gets pushed out. Measure the mm gap:



If you use something (a soft pencil maybe) that leaves a mark on the most 'buckled' part you can examine it afterwards at leisure, knowing where the 'buckle' is.

Doesn't solve the problem of course. 

[armstrongracer]

Need a tyre anyway, was going to take wheel to a fitter and get him to spin it up in the balancing machine which has proper taper centres. That should tell me if wheel is junked.

[andym2]

The rear disc is bolted to the hub, not the wheel, so you can compare the run out on the disc to the wheel rim. If the disc doesn't wobble the wheel is either loose or bent, if it does then the wobble is coming from the hub. The recall changed the flange the wheel bolts on to from aluminium alloy to steel so easy to see if it been done.

[armstrongracer]

Thanks for that info. Disk doesn't appear to wobble but that doesn't say that the hub bearings arent gone. Disk is much smaller diameter compared to the wheel so the 2 theta rule kicks in. Displacement is hugely magnified at the rim compared to the disc. Also the bearing at the wheel side of the transaxle could be the one gone causing the wheel to move but the disc to remain relatively still.  Transaxles and forged wheels are getting rare as the proverbial  hen's does anyone know if there is any part compatibility with later bikes such as the K1600 and GS models. I know some bearings are shared.
 

[armstrongracer]

Gets curiouser, took wheel off checked flange, was aluminum not steel but no cracks. Hmm.. Put my vin number into real oem and it says bike is July 2015 so should have the steel flange unless BMW modified the ally flange on post 2011 when the recall allegedly finished.  Either that or my bike had its drive box replaced for an older one, I know my bike had a crash in the past, search said it had been a class c write off. Had another look after replacing the wheel and spinning it again, the disc wobbles too so diff bearings are shot. Need to make, buy or borrow a puller.  Does anyone know if pattern ones are available, I'd say pukka bmw ones are €€€€