BMW 1250 Technical Recall

[Santa-2512]

I always thought the whole point of the paralever rear suspension didn't require the length of cardan shaft to change during suspension

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This is how i understand it .

The shaft is a fixed length, , inserted into a female spline at the gearbox, with no fwd longitudinal free play , but obviously some rear movement

(ie = to the length of the female spline)

At the cardan end though it goes both ways , so as you load the rear the cardan unit rotates one way, and the other as you unload the rear

so at the cardan end, the shaft stays the same, it's the cardan drive that moves up and down the shaft

when the shaft seizes, the rotational movement movement gets transferred to the other end, so the ride doesn't change, but the gearbox splines are then under a rubbing load

i think ?

 

[leadfarmer]

i think ?

No, with the paralever setup there is no change in length when the suspension moves, if there was the driveshaft would be fixed at each end with a sliding joint in the middle, like rear wheel drive car prop shafts

 

[Santa-2512]

No, with the paralever setup there is no change in length when the suspension moves, if there was the driveshaft would be fixed at each end with a sliding joint in the middle, like rear wheel drive car prop shafts

Ok I get that, but why does the cardan to driveshaft housing have a bellows, which does contract when you sit on the bike?. something is moving for it to do that

 

[Deleted account 250319001]

This is how i understand it .

The shaft is a fixed length, , inserted into a female spline at the gearbox, with no fwd longitudinal free play , but obviously some rear movement

(ie = to the length of the female spline)

At the cardan end though it goes both ways , so as you load the rear the cardan unit rotates one way, and the other as you unload the rear

so at the cardan end, the shaft stays the same, it's the cardan drive that moves up and down the shaft

when the shaft seizes, the rotational movement movement gets transferred to the other end, so the ride doesn't change, but the gearbox splines are then under a rubbing load

i think ?

Don't ruin Santas illusion that all our final drives / shafts are going to explode..... not today though, but maybe tomorrow ?

 

[Micko123]

2021 model R1250GS
Had mine done on 3rd October at Allan Jefferies (Baildon) as well as the normal service. When I got home (70 miles) the rear rubber gaiter had come out at the front. I thought they’d just not secured right so put it back myself. It was alright when I set off from AJ’s.
Next ride it came out again, clipped it back. After about five or six rides and it happening every time I thought rather than go through the hassle of booking it back in and travelling 70 miles when the weather is now a bit crap, I’d open it up a bit more so the gaiter could be refitted better. Wheel off, caliper off, sensor released and paralever bolt out allowed me to move it further without actually dropping all the way. I didn’t want my new final drive oil to pour out the sensor hole.
Nice new looking black shaft, they’d replaced it after the test, but there’s a one inch rotation direction scratch on the UJ that looks like it has made contact with the housing. I refitted it all making absolutely sure the gaiter was fitted correctly, fully secured all round.
Next ride it’s come adrift again so it’s booked in for 12th November. I think somehow the UJ is pushing it out and coming into contact with the outer casing, though AJ’s say this isn’t likely. I do feel a clunk ever now and then over rough roads or speed bumps etc.
I’ve said to them not to just put the gaiter back and send me on my way because it’s been done several times.

Maybe the gearbox end snap ring hasn't locked properly onto the female spline of the cardan shaft ?
Then in effect the the shaft has 'become too long' and rear suspension travel is causing shaft deflection allowing the rear UJ to contact the gaiter / cardan housing ?
Or the spring steel gaiter support clip hasn't been refitted properly. Let us know what the outcome is please.

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[team duvet]

Okay so keeping it simple, has anybody just said “you know what I will not have it done”

50/50 here.

TD

 

[Micko123]

Okay so keeping it simple, has anybody just said “you know what I will not have it done”

50/50 here.

TD

I think I will let them check mine on the vibration test and if a new shaft is req'd let them fit it, but I don't want a 10mm hole drilling and the cardan tube scratching.
I will then strip it again once home, lubricate both splines (front and rear) properly with moly paste and reapply Starburags to the gaiter. Like I did after the 1st running in service @ 600 mls.

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[KJB]

My view is if you bike is within warranty and you have refused to have it done then BMW May well void your warranty on the final drive, secondly hopefully your dealer will have advised you that after three years warranty it possible for another three years good will warranty so if you use a main dealer for service and then have a problem you may well get help, may not be 100% but certainly a great part of it. To clarify this my 1200GSA is out of warranty but just hade the complete final drive including gator replaced because it was seized solid but passed the the recall test upon further investigation they found a issue which was sorted FOC

 

[Biot]

Just had my shaft replaced. 2013 R1200GS with 50,000 miles. Only original thing on the bike from new are the wheels

 

[Santa-2512]

Don't ruin Santas illusion that all our final drives / shafts are going to explode..... not today though, but maybe tomorrow ?

Yawn, they wont,

they may seize, as did mine. And yours if i recall

 

[Piggers]

Shaft replaced on low mileage dry use bike.

I just had my be done and it only has approx 4,000 dry miles on it and is stored in a de-humidified garage, so should not be much chance of much water ingress and they needed to replace the shaft. Therefore to me it sounds like they may also be checking for poorly manufactured shafts at the same time.

 

[Victor c]

Little bit of an insight into the test carried out https://youtu.be/BMPMg_TlvCM

 

[tspivey]

And another one.

https://youtu.be/zdBjdxZwJ98

 

[tspivey]

Maybe the gearbox end snap ring hasn't locked properly onto the female spline of the cardan shaft ?
Then in effect the the shaft has 'become too long' and rear suspension travel is causing shaft deflection allowing the rear UJ to contact the gaiter / cardan housing ?
Or the spring steel gaiter support clip hasn't been refitted properly. Let us know what the outcome is please.

Sent from my SM-G981B using Tapatalk[/QUOTE
Took it in on Monday and their verdict was that the gaiter was twisted out of shape, I can agree with that as I noticed it was not central on the several occasions I refitted it. A new gaiter was fitted after they’d dropped the final drive. They say the scratch on the UJ is just paint and could have been done during fitting and is nothing to be concerned about. I rode over every speed bump I could find on the way home and it’s all fine again.

 

[10tenmen]

Drive shaft failure.

Just seen this on F book BMW club a complete failure of the drive shaft whilst riding 2017 RT 1200, BMW picked up the repair bill minus 50% of the labour as a goodwill gesture. A lucky man.

 

[Micko123]

Oooh an exploding drive shaft, expect a comment from Onahi soon... popcorn

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[Deleted account 250319001]

I didn't intend to reply, however.......
It's a machine. Machines fail.
In direct response to this image though......
How many produced. To how many have done that.....?
Prospective.
However, posting this image on here will greatly enhance the illusion that all our UJ's on our drive shafts will explode !

 

[Micko123]

Only teasing my friend, I thought you would respond immediately

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[Deleted account 250319001]

Never like to dissapoint !!!!!!

 

[10tenmen]

I didn't intend to reply, however.......
It's a machine. Machines fail.
In direct response to this image though......
How many produced. To how many have done that.....?
Prospective.
However, posting this image on here will greatly enhance the illusion that all our UJ's on our drive shafts will explode ! ��

I’m sure that had any maintenance been carried out this would not have happened, hats off to Bmw for picking up the bill though.
The point of posting was not to alarm but to point out that regular maintenance is crucial.