Get The Sandwiches Ready GSA Rear Wheel Collapse - Part 3!

Warlord

Do Not Resuscitate
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There's more forum threads collapsing than wheels on this topic.

I'd like to keep it open, as more info can be added.

So far we've learned....

A) It's still an open case and no actual cause has been established yet.

B) There was a wheel manufacture change around 2012, but no relavance is yet applied to this.

C) Speculation aimed at cause....

i) Operator error, not tightening bolts after DIY Service

ii) BMW dealer error, mechanical failure in some way

iii) Caliper bolts coming loose
iv) Spokes on wheel coming loose due to rim damage or grub screws falling out

D) Remedies suggested are

i) to check bolts and apply tamper proof paint for easy visual check on any bolt movement.

ii) to always replace bolts with brand new ones from BMW, as they are microencapsulated already with thread lock.

E) You dont need to remove caliper to change pads, but you should clean pistons before pushing them back through the seals.

Thats about it I think.
 
"B) There was a wheel manufacture change around 2012, but no relavance is yet applied to this."
The wheels are made in the Berlin factory, seen with my own eyes.Could be new operatives though.??? who knows
But they are definately made their
 
"B) There was a wheel manufacture change around 2012, but no relavance is yet applied to this."
The wheels are made in the Berlin factory, seen with my own eyes.Could be new operatives though.??? who knows
But they are definately made their

Rims are different now, made by Giant
 
How many of these bikes with spoke wheels have been sold, and how many have had a caliper fall off, scales obviously tip in BMW way.
 
There isn't a huge amount of clearance between the caliper and spokes.
 

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I don't understand why people are happy to change their brake pads and not remove the caliper?

Yes I understand it can be done, but why would you just push the pistons back through the seals, with all the crud left on them?

Surely cleaning the pistons properly before pushing them back is the proper thing to do, and how can you do that properly with the caliper still bolted on?

I don't get it?
 
I don't understand why people are happy to change their brake pads and not remove the caliper?

Yes I understand it can be done, but why would you just push the pistons back through the seals, with all the crud left on them?

Surely cleaning the pistons properly before pushing them back is the proper thing to do, and how can you do that properly with the caliper still bolted on?

I don't get it?

Tis true. Handy if you need to keep the pins and existing pads clean and free though.
 
Checked my spokes today and found two very loose spokes on the rear wheel on the right side,a lot of the other spokes more movement than there should of been,also has movement 6-12 oclock if you rock it back and forth you can actually see the rim moving.1200 GSA bike has only done 200 miles dealer is picking it up Tuesday.30 minutes prior to finding this i was having lets say a spirited ride.!!
 
Checked my spokes today and found two very loose spokes on the rear wheel on the right side,a lot of the other spokes more movement than there should of been,also has movement 6-12 oclock if you rock it back and forth you can actually see the rim moving.1200 GSA bike has only done 200 miles dealer is picking it up Tuesday.30 minutes prior to finding this i was having lets say a spirited ride.!!

That sounds pretty worrying, especially the rim movement. It seems that there is not much clearance between spokes and caliper, so if the spokes loosen enough to let the rim move, the wheel might flex enough under cornering forces for the spokes and caliper to make contact, leading to a destructive chain reaction. This could explain a wheel collapse where the caliper has not come adrift.
 
How many of these bikes with spoke wheels have been sold, and how many have had a caliper fall off, scales obviously tip in BMW way.

This is the crux of the matter, that or how many spoked rear wheel failures have there been compared with wheels of the same design.
 
Has there been any?

I've no idea - just putting it forward as a possibility, as spoked wheels with tubeless tyres, such as BMW's, tend to have the spokes very close to the edge of the wheel. This evidently leaves less margin for error, for example in the event of deterioration in the condition of the spokes bringing them into contact with the caliper.
 
I've no idea - just putting it forward as a possibility, as spoked wheels with tubeless tyres, such as BMW's, tend to have the spokes very close to the edge of the wheel. This evidently leaves less margin for error, for example in the event of deterioration in the condition of the spokes bringing them into contact with the caliper.

Maybe there is some flex in the drive shaft swing arm which allows the brake caliper to move closer to the spokes as you accelerate or decelerate :nenau :D
 


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