no drive!

[johnr1100s]

Hi Jason,

with shaft attached and bike in gear, if I grab bevel box end of shaft I can rotate shaft, if I grab gearbox end its solid.... I even wedged a screwdriver into UJ to see if I could make it spin... and its solid until it turns engine....

I'm sure that box hasn't failed 'cos I would have still got that spliny grating..... as I turned gearbox to engine.


Do you know what the stuff leaking from the shaft is, its not grease more melted plastic thats still warm or silicone like.

As I grab both end of shaft assembly they rotate independantly, and make a spliny rubbing noise!!

John

[gus]

So you can grab the shaft and roatate each end independantly of each other?
As i said in a earlier post,i thought the shaft was made ofv two parts with a built in dampner.
I think that it is the dampner that has given up the ghost by your description.It would stink of rubbery/plastic if its been spinning and melting.
From the manual.....................two piece shaft drive with universal joints at each end.central sliding joint and integral torsional vibration damper......
Hopefully this is the case.Easy fix with a S/H shaft and less money.
Good luck
gus

[bigblackfalco]

Hi Jason,

with shaft attached and bike in gear, if I grab bevel box end of shaft I can rotate shaft, if I grab gearbox end its solid.... I even wedged a screwdriver into UJ to see if I could make it spin... and its solid until it turns engine....

I'm sure that box hasn't failed 'cos I would have still got that spliny grating..... as I turned gearbox to engine.


Do you know what the stuff leaking from the shaft is, its not grease more melted plastic thats still warm or silicone like.

As I grab both end of shaft assembly they rotate independantly, and make a spliny rubbing noise!!

John

Sounds like the splines that the UJ's mount onto.Never heard of the damper failing.....could this be a first?!
Bailey.

[Jason M]

Hi Jason,

with shaft attached and bike in gear, if I grab bevel box end of shaft I can rotate shaft, if I grab gearbox end its solid.... I even wedged a screwdriver into UJ to see if I could make it spin... and its solid until it turns engine....

I'm sure that box hasn't failed 'cos I would have still got that spliny grating..... as I turned gearbox to engine.


Do you know what the stuff leaking from the shaft is, its not grease more melted plastic thats still warm or silicone like.

As I grab both end of shaft assembly they rotate independantly, and make a spliny rubbing noise!!

John

Well you learn something every day So it looks like there is a damper in there according to Gus and by the looks of your evidence then it looks like it has come detatched from the outer shaft then spun round and melted - I've never heard of that before - lucky you

I would take it to a dealer and show them - see if they've ever had it before. Still - it's an easier and cheaper fix than you thought isn't it. That's good news.

Did you say your bike is chipped and tuned? Might be pushing more torque through than some of ours are and that's led to the fault.

Jason

[johnr1100s]

thats a nice thought Jason.... my bikes better than yours etc,

erm... yes I took all the bits back to motorworks today, I was in the area... ahem!! And picked up a driveshaft.... you can see a section of rubber in between the shafts.... I'll get a photo later.

They said the shaft was 'S' specific.. but had a secondhand one... so hopefully all done at £95.


Also I think I found the chaffed wire to the clock... so will fix that tomorrow too.


I'll let you know when it's running again!!


John

[nab 301]

Have you got ABS? Hopefully not cos it makes life a little more difficult as you don't want to disconnect the caliper from the ABS system I suspended mine from a ring in the ceiling with a bungee.

Jason

Jason , could you explain pls? . I have changed the fluid on my bike but never dismantled the brakes . Are they difficult to bleed from scratch?
(Brembo early abs )
Nigel B

[Jason M]

Have you got ABS? Hopefully not cos it makes life a little more difficult as you don't want to disconnect the caliper from the ABS system I suspended mine from a ring in the ceiling with a bungee.

Jason

Jason , could you explain pls? . I have changed the fluid on my bike but never dismantled the brakes . Are they difficult to bleed from scratch?
(Brembo early abs )
Nigel B

Hi Nigel - I'm no expert by any means at this but I think the problem with the ABS is that BMW have to 'vacuum' bleed the system rather than just bleed as normal. If you disconnect the read caliper and bubbles find their way back up into the ABS pump then that's probably not good.

Having said that - you can easily buy vacuum bleeders yourself - I had to change the rear caliper lately so I thought I'd just crimp the hose with some mole grips to stop too many bubbles entering the system - fitted the new caliper, then went to bleed as normal by pumping the pedal when BOSH - suddenly the rear brake hose fractured and blew brake fluid all over me. I must have weakened the hose with the moleys I bought a cheap kit off ebay for under a tenner that is basically just a few tubes, a valve and a big syringe - then I 'sucked' the fluid through the system without ever pumping the levers - worked a treat. The back brake has not felt so good in AGES.

I stand to be corrected though - it mught be bleedable in a standard fashion but I didn't think so because of all the abs valves involved.

Jason

[Steptoe]

Well you learn something every day So it looks like there is a damper in there according to Gus and by the looks of your evidence then it looks like it has come detatched from the outer shaft then spun round and melted - I've never heard of that before - lucky you

It happens fairly frequently , especially on the GS.

Usually caused by non sympathetic use

[nab 301]

Jason

Nigel B

Hi Nigel - I'm no expert by any means at this but I think the problem with the ABS is that BMW have to 'vacuum' bleed the system rather than just bleed as normal. If you disconnect the read caliper and bubbles find their way back up into the ABS pump then that's probably not good.

Having said that - you can easily buy vacuum bleeders yourself - I had to change the rear caliper lately so I thought I'd just crimp the hose with some mole grips to stop too many bubbles entering the system - fitted the new caliper, then went to bleed as normal by pumping the pedal when BOSH - suddenly the rear brake hose fractured and blew brake fluid all over me. I must have weakened the hose with the moleys I bought a cheap kit off ebay for under a tenner that is basically just a few tubes, a valve and a big syringe - then I 'sucked' the fluid through the system without ever pumping the levers - worked a treat. The back brake has not felt so good in AGES.

I stand to be corrected though - it mught be bleedable in a standard fashion but I didn't think so because of all the abs valves involved.

Jason

I've always used a vacuum pump/ syringe when changing the fluid so maybe that's why i never encountered any problems.
Thanks , Nigel B.