Cushdrive/Sprocket carrier play?

[Beamish]

Hi,
Whilst changing out a rear tyre prior to a Cadwell trackday, I noticed that the play once the sprocket carrier is located in the wheel was probably about 3mm before the cush rubbers were engaging. Anyone noticed this? I have worked on plenty of bikes and even when the cush drive rubbers are fecked the sprocket carrier is a better fit into the wheel! When they are well worn they become very soft and you can twist the sprocket carrier easily but on this bike 2012 (1500 miles) the rubbers are nice and hard but the play before they take up the drive seems excessive. Is this some BMW design? I have rung BMW and they say bring it in but as the place is 50 miles away and its bloody snowing I will wait for better weather. I am still recovering from the trackday on Sat, it wasd as you might say........interesting (read fecking frightening).
P.S Dunlop qualifier rears on the S1K are shite! I will replace as soon as possible.

 

[Shft_Ctrl]

I had mine replaced along with the entire sprocket carrier, under warranty - I initially thought it was the sprocket carrier bearing but the dealer decided to only replace the cush drives (which slightly improved the amount of play) but I insisted they replaced the bearing (they opted to replace the entire s/carrier) - which removed 99% of the play, and reduced the d/l/shunt. I checked the amount of play on the bikes in the shop and they had almost zero...but their 1200 mile demo bike was worse than mine (both had lateral as well as rotational play). They play is starting to return after only 500 miles.

 

[Beamish]

Thanks, so what do you think could be a more permanent cure? Basically a better quality Cush drive rubber should help don't you think?

 

[Beamish]

Looking on the US forum it seems we are not alone. I was going to ask the race teams but they will prob be using a bat wheel or similar. I will see what happens at the dealers.

 

[Ducky]

I've heard of a few people having cush drives replaced on the US forum a while back, not sure if it wears prematurely or there is an actual fault somewhere...still with almost 200 horsepower going through the drive train I wouldn't be surprised they wear faster than expected.

 

[Beamish]

Sorry that should say BST ( fecking iPhone)

 

[Beamish]

Agreed but after 1500 miles 600 of which were running in!

 

[bananaman]

hmm... phoned my daler with a similar problem, with the wheel torqued up there was still plenty of play, he said that new bikes in the showroom were the same...........

 

[Beamish]

hmm... phoned my daler with a similar problem, with the wheel torqued up there was still plenty of play, he said that new bikes in the showroom were the same...........

WTF! There is no way on earth that you should have any lateral play in the sprocket carrier (which I now have I discovered this morning) how on earth can you accurately set up the chain tension with that much play on accel/decel? He is talking rubbish.

 

[Shft_Ctrl]

Thanks, so what do you think could be a more permanent cure? Basically a better quality Cush drive rubber should help don't you think?

No idea TBH but it definitely isn't right - and like I said, the s/c/bearing seemed to be where most the play was as you could twist the sprocket diagonally

 

[Beamish]

No idea TBH but it definitely isn't right - and like I said, the s/c/bearing seemed to be where most the play was as you could twist the sprocket diagonally

Took mine in today, I have mentioned that just replacing the cush rubbers would be unacceptable. The mech is a good guy and he won't try and fook me over.

 

[babarr46]

Try packing some grease around the Cush drive or wrap the rubbers in ptfe tape. I've checked most of the bikes in the dealers & they've got about the same free play as mine with 25k on the clock.

 

[Beamish]

Try packing some grease around the Cush drive or wrap the rubbers in ptfe tape. I've checked most of the bikes in the dealers & they've got about the same free play as mine with 25k on the clock.

Mine was totally shot, BMW are fitting a new carrier, bolts and Cush rubbers. Greasing or packing the rubbers on mine would not have removed the lateral play so the chain/sprockets would be mashed within a thousand miles and the gear change would feel terrible. I haven't heard of a 2010/2011 bike with this problem! My bike came with a complimentary track day so bm can't complain that it is misuse, surely they have been designed with track use in mind! Lets hope the new components remove the problem full stop.