Noise from engine - not the normal one!

[gb's]

Chap doing my MOT noticed this noice from rear of engine when he had it running on the centre stand, must admit have never noticed it but it does sound bad. recording taken at the rear of the engine around the drive shaft. Anyone have any ideas what it might be? Bike is o4 1200 GS with c33000m.
<iframe width="420" height="315" src="https://www.youtube.com/embed/64xJjry1h84" frameborder="0" allowfullscreen></iframe>
Thanks

 

[G5RJO]

Was it in gear?

If it was in gear with the engine running it'll be turning the drive shaft at an angle that is well beyond where it wants to be. It'll be a LOT straighter with someone sat on it. That noise sounds like the driveshaft moaning

Take it somewhere else for the MOT next time if he did run it in gear on the centre stand. It's really not a good idea.

Roger.

 

[gb's]

Thanks Roger, that would explain why I've not heard it when riding - I never run it in gear on the centre stand, today's sound recording excepted!

 

[BlueBird]

Back lash in drive train

also check the drive shaft UJ where it comes out of gearbox, i had one go and it was just the two forks meshing, needle rollers all in the bottom of swinging arm, ridng round for weeks before i noticed it was kaput.

 

[TLSgazza]

also check the drive shaft UJ where it comes out of gearbox, i had one go and it was just the two forks meshing, needle rollers all in the bottom of swinging arm, ridng round for weeks before i noticed it was kaput.

Sounds like mine did and my drive shaft was pretty much as described above, mine was replaced under the extended warranty.

 

[Bendy toy]

My front UJ was fine at 50K miles. The back UJ however had an an obvious loose patch around its normal range of motion then stiff either side. The rollers were shot, repaired by MikeyBoy.

 

[gb's]

Thanks for the comments. Going to get it checked out, fingers crossed not too expensive.

 

[Pukmeister]

On a recent 'Wander' one of the 1200 riders (Timeandtide) had his driveshaft let go prematurely at the gearbox end, spoiling his trip.

I checked my bikes driveshaft and found tight spots in the joint where it doesn't move through much of an angle in normal use.

I fitted a replacement driveshaft from an ebay breakers yard in UK from a low mileage 1200 wreck, I shall either refurb my old one myself or get mikeyboy to do it at some point in the future.

If removing your driveshaft to inspect it, be sure to lube the splines with some molybdenum disulphide based grease before reassembly.

 

[gb's]

Thanks Adam.
Have the bike booked in with Jim Hill of long Eaton for a service and a look / listen at the noise.

 

[Bendy toy]

I am sure that noise is drive shaft backlash caused by running in gear on centre stand. Even a car is noisy if its run in gear at tick-over with wheels off the ground.

 

[gb's]

I am sure that noise is drive shaft backlash caused by running in gear on centre stand. Even a car is noisy if its run in gear at tick-over with wheels off the ground.

That's what Jim (Hill) thinks, Have had the opportunity to listen to a couple of other bikes now and it does appear "they all do it".