The dreaded gearbox main shaft failure ...

[mikek_7]

Coming back from the Dolomites this year and enjoying the roads on the roads on the France/German border when ...

http://youtu.be/Gaw2apESPvM

... made it home with as little gearchanging as possible, although filtering on the M25 was not much fun. And yes, it really was that loud, my mate behind could hear the clonks.
Stripped bike when I got back, clutch wear was only about 50% (at 38k) but the splines were completely mullered.

Well, it'll give me something to do over the winter

[Caragh]

Ouch sounds painful and expensive

[namesarefortombstones]

mine used to do that, my splines were mint, it turns out that the input shaft damper was not doing it's job as a shim had self destructed, easy way to tell is get the rear wheel of the ground, select 1st, turn the wheel against the gear resistance, you should feel the wheel spring back some when you let go if the damper is ok.

[Neil178]

I thought that 2004 bikes were safe from the chocolate splines. What is the mileage if you dont mind my asking?
Sorry it happened mate, a bad time of year to be splashing the cash. At least you have a while to do it before the warmer months return. Good luck with it.

[sykospain]

Bad news and sorry it spoilt your holiday. Once again, blame Berlin for the design fault in hydraulic clutches on each and every 6-speed boxer. The friction-plate's splined hub is too short to fully engage the plate onto the full length of the gearbox input shaft splines, causing wobbles, accentuating any slight engine-casing-to-gearbox misalignment thus causing premature failure.

Thankfully there's another option than just handing over a grand or more in sterling to your local BMW Stealer, who'll simply replace the clutch plate with a new one having an equally too-short hub.

The answer is to fit a 6mm spacer into the replacement friction plate.
E- me for the details of the solution to the problem - it involves 3 days of your valuable time and labour and it's not as horrendous a task as you might think.

This Chris Harris video explains in detail why it happens...
http://youtu.be/dRW6SP9eMYs

And whilst it's in bits, replace the stupidly under-specc'ed slave cylinder :
http://youtu.be/xXyx4Dwx7Mw

And its fatuous redundant fluid bleeder appendage :
http://youtu.be/udpZPKoEH50

Best o' luck !

AL in s.e. Spain
al at alansykes dot com

[mikek_7]

mileage is 38k. Looking at video from this year and last years trips, it obvious now that its been gradually getting worse, but as its gradual, I hadn't noticed it.

I thought that 2004 bikes were safe from the chocolate splines. What is the mileage if you dont mind my asking?
Sorry it happened mate, a bad time of year to be splashing the cash. At least you have a while to do it before the warmer months return. Good luck with it.