Final Drive End Play

[Pierce]

Does anyone know what the tolerance(slop) is on the end play(side to side)of the final drive on a R1150RT? And no flamming on my grammar or spelling! Pierce

[Jerry Johnston]

Near as I know there shouldn't be any. I have a R1100RT and can't find any play side to side. Forward and back however is a different story, I have about 2" f. to b. Bike has 58k mi. on it.

[FlyingFinn]

What? You have 2" front-to-back play in the rear wheel? Ever notice any negative effects in the way the bike handles?

 

Going back to the original question. There shouldn't be any side-to-side play but the pivot bearing design is just so bad for this application that on many (if not most) oilheads you will find little play there. If the play is small (you can FEEL it in the rear wheel but you can't SEE any movement) you can probably get rid of it by just re-tightening (per spec) the pivot bolts.

Replacing the bearings is really easy to do too, actually not much more work than properly re-tightening the bolts.

--

Mikko

[Jerry Johnston]

What? You have 2" front-to-back play in the rear wheel? Ever notice any negative effects in the way the bike handles? Mikko

Why should I? I believe it's normal gear lash.

[Bob Palin]

Near as I know there shouldn't be any. I have a R1100RT and can't find any play side to side. Forward and back however is a different story, I have about 2" f. to b. Bike has 58k mi. on it.

Do you mean that the wheel freely rotates 2" or that the axle can move 2" b&f (can't imagine the latter!)

[Joe Frickin' Friday]

What? You have 2" front-to-back play in the rear wheel? Ever notice any negative effects in the way the bike handles? Mikko

Why should I? I believe it's normal gear lash.

 

OK, you guys are talking about different things. Gear lash is fine; slop in the bearings that support the wheel, final drive, or swingarm is not.

 

Slop in the final drive pivot bearings or swingarm bearings is an annoyance that will eventually result in sloppy handling and should be replaced when it's convenient.

 

Slop (or noise) in wheel bearings is a dangerous phenomenon that can lead (and has led) to catastrophic, at-speed failure. Fix this immediately.

 

To locate the slop, put the bike on the centerstand and then:

 

Grab the swingarm just forward of the final drive and vigorously wiggle it side-to side.

 

If you DO hear/feel slop, the problem is the bearings at the front of the swingarm.

 

If you DO NOT, then

 

Grab the final drive unit and vigorously wiggle side-to-side and then up/down.

 

If you DO hear/feel slop, the problem is the pivot bearings at the front of the final drive unit.

 

If you DO NOT, then

 

Grab the wheel and vigorously wiggle side-to-side and up/down with gearbox in neutral. Try not to rotate the wheel while you do this; you're looking for wheel bearing slop, so you don't want to generate driveline noise that might result in a misdiagnosis. If you feel slop when you do this - or hear/feel vibrations from the final drive, drain the oil out of it and check for chunks of metal in the oil and on the drain plug. If you've got chunks, it's time to go shopping for a new final drive unit (or visit your shop for warranty replacement).

[Jerry Johnston]

Sorry I didn't make that more clear - I'm talking gear lash and no bearing play.

[dcm3]

... and I believe that the tests Mitch describes must be carried out cold. Any riding or warming up of the drive train can take the slop out of the feel and give you an erroneous result.

[Pierce]

Thanks for the info Mitch. You understand my question correctly. No, I can't see any play, but it feels like the wheel moves about a mm, maybe a tad more side to side(based on my calibrated feeler hands). Now, is it bearings, or the pivot pin? That's what I have to find out next. I do have a local independant to take the bike to, but he is more old school than new. Pierce