Get The Sandwiches Ready - GSA Rear Wheel Collapse

[Mr Bean]

Screws

Fredaroony, you may have checked the parts list for all LC bikes and found the same replacement caliper screw part number - this is true. However, in 2015 the rear caliper screws were not considered single use - see attached image from the RSD. No mention of new screws or requiring micro-encapsulated screws.

 

[Deleted account 191119001]

Fredaroony, you may have checked the parts list for all LC bikes and found the same replacement caliper screw part number - this is true. However, in 2015 the rear caliper screws were not considered single use - see attached image from the RSD. No mention of new screws or requiring micro-encapsulated screws.

Well lets just say the both Mr Bean and Fred are correct as BMW has a history of not making things mega clear and slightly adding things into their service manuals that they omitted before, but one thing is for sure both OP,s have cleared the air, and I for one would not want copaslip on a caliper bolt, and I cannot even see the reason for the copaslip given the torque is only 24Nm, its not like it is wellied into the hole.

 

[fredaroony]

Fredaroony, you may have checked the parts list for all LC bikes and found the same replacement caliper screw part number - this is true. However, in 2015 the rear caliper screws were not considered single use - see attached image from the RSD. No mention of new screws or requiring micro-encapsulated screws.

I set my manual to baseline construction status and August 2013 build, both say install new screws. My manual is dated 06/2016

 

[Mr Bean]

I set my manual to baseline construction status and August 2013 build, both say install new screws. My manual is dated 06/2016

Fair enough.

Incidentally, in post 311 I said that I thought they changed in 2016 and your post confirms it - mine is a 2015 version and no mention

 

[sven]

I set my manual to baseline construction status and August 2013 build, both say install new screws. My manual is dated 06/2016

It’s not unusual to change the maintenance process during the lifecycle of a product. The problem is that the maintainer may never update their service manuals, so will be unaware of the changes, especially if they are a third party.

We frequently found that our service engineers were using old manuals, so we now keep them on a central server which they can read from their Android tablets.

If it’s a process change due to a safety critical issue, then a safety bulletin would be sent to the owner and issued via our trade association.

 

[fredaroony]

It’s not unusual to change the maintenance process during the lifecycle of a product. The problem is that the maintainer may never update their service manuals, so will be unaware of the changes, especially if they are a third party.

We frequently found that our service engineers were using old manuals, so we now keep them on a central server which they can read from their Android tablets.

If it’s a process change due to a safety critical issue, then a safety bulletin would be sent to the owner and issued via our trade association.

Totally understand, things like this change over time for various reasons. I imagine you would also follow the correct procedure once you found out about it

 

[Deleted account 191119001]

I set my manual to baseline construction status and August 2013 build, both say install new screws. My manual is dated 06/2016

Anyway Fred seems guys going back to 2013 just reused the bolts, as we can see in this video, not saying it is the correct way now, but it tallies up to what Mr bean was saying, so seems again BMW are not clear and have added on to a manual somewhere.

 

[fredaroony]

Anyway Fred seems guys going back to 2013 just reused the bolts, as we can see in this video, not saying it is the correct way now, but it tallies up to what Mr bean was saying, so seems again BMW are not clear and have added on to a manual somewhere.

Hey look, I'm not BMW and I'm only going by the updated BMW manual that covers the very first LQ boxers. They must have updated it at some point but if it says one use only, it means one use only.

Anyone can argue with BMW if they want.....

 

[Deleted account 191119001]

Hey look, I'm not BMW and I'm only going by the updated BMW manual that covers the very first LQ boxers. They must have updated it at some point but if it says one use only, it means one use only.

Anyone can argue with BMW if they want.....

Nobody really arguing with anybody Fred, it just shows that there seems to be several ways that BMW or others done their maintenance on the brakes, so anything is possible, at the end of the day we will never know until someone dies, then the Johnnyboxer snipes might start to worry a little.

 

[Engineer]

What other bolts should we be worrying about? I am worried that I am not worrying enough.

 

[Deleted account 191119001]

Anyway back to a theory, if we look at the wheel itself, it looks like it has kept its shape, no visible damage, except the spokes in the middle, so could it be possible that the rear caliper binded just enough to rip itself from the mounting bolts, put the caliper on a collision course with the spokes, I have a funny feeling, this could be the issue, given that new pads installed.

 

[Warlord]

Anyway back to a theory, if we look at the wheel itself, it looks like it has kept its shape, no visible damage, except the spokes in the middle, so could it be possible that the rear caliper binded just enough to rip itself from the mounting bolts, put the caliper on a collision course with the spokes, I have a funny feeling, this could be the issue, given that new pads installed.

I couldn't see any heat marks on the rear disc though, it appears clean.

 

[Deleted account 191119001]

I couldn't see any heat marks on the rear disc though, it appears clean.

Look at the disc behind the caliper there some nasty dark marks, however that could be oil coming out of the final drive, hard to see the photos, and taken at night, would be good if we had some daytime photos, but doubt that will happen now.

 

[Victor c]

Now I have got my laptop back and can see the pictures more clearly, this is my take on it.

Calliper rear mounting bolt has unscrewed (evident by it still being there and no sign broken final drive lug or calliper attached to it), rear of the calliper has floated upwards due to rotation of the disk, calliper has fouled spokes and this has in turn wrenched the calliper sideways, snapping the calliper forward mount.

Just my additional two penny worth...

 

[Deleted account 191119001]

Now I have got my laptop back and can see the pictures more clearly, this is my take on it.

Calliper rear mounting bolt has unscrewed (evident by it still being there and no sign broken final drive lug or calliper attached to it), rear of the calliper has floated upwards due to rotation of the disk, calliper has fouled spokes and this has in turn wrenched the calliper sideways, snapping the calliper forward mount.

Just my additional two penny worth...

Highly possible scenario, you might just be right.

 

[GrinningGSer]

My rear most caliper slide pin is very close to the disk on the inbound side, could it move further inwards or it’s exit towards the near side , I am not sure??? ; if it were to be meddled with could there be a chance of catching the disk arms and that would surely rip the caliper from the drive housing in an upwards direction .
I cannot see evidence of that in the pic , but the incident could be momentary and on the non visible part of the disk .

 

[Deleted account 191119001]

My rear most caliper slide pin is very close to the disk on the inbound side, could it move further inwards or it’s exit towards the near side , I am not sure??? ; if it were to be meddled with could there be a chance of catching the disk arms and that would surely rip the caliper from the drive housing in an upwards direction .
I cannot see evidence of that in the pic , but the incident could be momentary and on the non visible part of the disk .

Funny you say that, just came back from a nice twisty 150 kms in the Black forest, rear bolts intact, and paint line still in same place, however I noticed that the 2 little clips that hold the pin in in the picture below, have a blob of white paint on them, its not from me, maybe BMW quality control.

 

[GrinningGSer]

Smogbob, aren’t those the pad retaining pins ?
I am now not sure what I am referring to , but what is this arrowed and very close to the disk ?

 

[Santa-2512]

Smogbob, aren’t those the pad retaining pins ?
I am now not sure what I am referring to , but what is this arrowed and very close to the disk ?

Looks like part of the calliper carrier , (use a smaller arrow )

 

[GrinningGSer]

It has a rubber cap on the left and a metallic end on the right: very very close to the disk !