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### 2020 R1250RT Leaking Front Brakes After Recall Video ###

It seems to me that if the fault as described on here is due to improper machine work on the calipers themselves only replacing the seals would not fix anything. The repair would need to include new calipers that do not have the machine work out of spec. I hope you get it fixed properly soon and that you get to ride again as well.:thumb


I've had the seals replaced first and they still leaked. Then the calipers were replaced from the recall and they still leaked. I think the problem is Hayes calipers are two pieces and bolt together (This is where they leak, I think), where the Brembo calipers are a one piece design, this is what I was told.

Steve
 
It is my understanding that the two halves are sealed with an O ring and that the groove(s) for that O ring were machined slightly too deep causing the leak. That understanding was gleaned from a couple of BMW and NHTSA documents somebody quoted somewhere so it is second hand if not third hand. And as always it could be wrong. The internet is like that.
 
I've had the seals replaced first and they still leaked. Then the calipers were replaced from the recall and they still leaked. I think the problem is Hayes calipers are two pieces and bolt together (This is where they leak, I think), where the Brembo calipers are a one piece design, this is what I was told.

Hmmm... every Brembo caliper I’ve rebuilt has been a two-piece unit, bolted together and sealed by an o-ring. But, I have yet to service any of the newer radial-mount calipers. Machining piston bores in a billet block would require an external “plug” to seal the borehole, and I’ve not seen any calipers sporting that feature.

Could a thicker seal work?

Possibly, but at some point down the road that caliper will need servicing again-and how would one determine which o-ring, std or oversized, to use?

Replacing the calipers with properly-machined units is the only real solution to mis-machined calipers. Anything else just creates a future maintenance problem. But then, I’ve seen other manufacturers punt a problem down the road like that.

Best,
DeVern
 
Hey guys,

I just talked to BMW, it looks like they want to inspect the bike on Wednesday the 21st. They said they'll pick up the bike the day before and two BMW engineers will be there when they do the inspection. I asked him if it would be filmed (as I think it should be), but he didn't say that it would be, he wasn't sure. The guy at NHTSA will be on a zoom call while they remove the calipers and are inspected. They're having my bike taken to a dealer where it has never been serviced. They said they'll install new calipers at that time, then deliver my bike back to my home. Fingers crossed they can resolve this.

Steve
 
Hey guys,

I just talked to BMW, it looks like they want to inspect the bike on Wednesday the 21st. They said they'll pick up the bike the day before and two BMW engineers will be there when they do the inspection. I asked him if it would be filmed (as I think it should be), but he didn't say that it would be, he wasn't sure. The guy at NHTSA will be on a zoom call while they remove the calipers and are inspected. They're having my bike taken to a dealer where it has never been serviced. They said they'll install new calipers at that time, then deliver my bike back to my home. Fingers crossed they can resolve this.

Steve

Sounds like progress :thumb
OM
 
Hey Guys,

Off to the dealership today. This is the fifth time for the leaking calipers.

Steve


Steve,

I hope your bike made it to the shop without falling, I noticed the bike was up on the center stand, see your owners manual. Good luck getting your brakes worked out!
 
Hey Guys,

Off to the dealership today. This is the fifth time for the leaking calipers.

Steve


I had the same (one time, not five) experience, in June of '14, when my '14 RT was hauled away for the rear strut debacle. I didn't get the bike back however, I did receive a check refunding all my costs of purchasing, registering and licensing the "DO NOT RIDE" machine. It does look good on the truck. Might it have more miles being trucked, than under its own power? Hope this time is the charm.
 
Steve,

I hope your bike made it to the shop without falling, I noticed the bike was up on the center stand, see your owners manual. Good luck getting your brakes worked out!


This is the company BMW set-up to get the bike to the dealership and if it fell off I'm sure they would have given the driver a bonus. Hopefully it's finally going to get the leaking caliper issues resolved.

Steve
 
I gotta know the outcome.

I should know something tomorrow when the two BMW engineers inspect the brakes with the investigator from the NHTSA, stay tuned. It's not good when you do a recall and the new recall calipers leak even worse than the original ones.

Steve

 
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Hmmm... every Brembo caliper I’ve rebuilt has been a two-piece unit, bolted together and sealed by an o-ring. But, I have yet to service any of the newer radial-mount calipers. Machining piston bores in a billet block would require an external “plug” to seal the borehole, and I’ve not seen any calipers sporting that feature.



Possibly, but at some point down the road that caliper will need servicing again-and how would one determine which o-ring, std or oversized, to use?

Replacing the calipers with properly-machined units is the only real solution to mis-machined calipers. Anything else just creates a future maintenance problem. But then, I’ve seen other manufacturers punt a problem down the road like that.

Best,
DeVern


The Brembo's on my 2019 (had them switched prior to purchase) are monoblock. I really hope this gets resolved soon. Its such an amazing bike otherwise. No excuse for this...... Brake calipers aren't new technology.
 
I really hope this gets resolved soon. Its such an amazing bike otherwise. No excuse for this...... Brake calipers aren't new technology.

This issue isn't really a mechanical issue. It is a corporate responsibility issue and BMW is earning an "F".

The mechanical defect is apparently that a robotic computer controlled machine cut grooves a little too deep so the O rings fail to seal properly. This kind of error can happen in any mechanized manufacturing process. The real issue is that BMW seems to be dancing around, replacing bad calipers with new bad calipers. Hayes, the US based company that built the calipers, appears not to know the dates that bad calipers were built and/or sent to BMW. The remedy should actually be pretty simple. BMW and Hayes should throw in a big pile every caliper that they do not know to be good. Every one of these should be replaced with known good calipers.

Then, if Hayes thinks it would be cost effective they can hire high school students to take the suspect calipers apart to inspect and measure the depth of the machined grooves. If found to be good they can hire 8th graders to put the good calipers back together.
 
This issue isn't really a mechanical issue. It is a corporate responsibility issue and BMW is earning an "F".

The mechanical defect is apparently that a robotic computer controlled machine cut grooves a little too deep so the O rings fail to seal properly. This kind of error can happen in any mechanized manufacturing process. The real issue is that BMW seems to be dancing around, replacing bad calipers with new bad calipers. Hayes, the US based company that built the calipers, appears not to know the dates that bad calipers were built and/or sent to BMW. The remedy should actually be pretty simple. BMW and Hayes should throw in a big pile every caliper that they do not know to be good. Every one of these should be replaced with known good calipers.

Then, if Hayes thinks it would be cost effective they can hire high school students to take the suspect calipers apart to inspect and measure the depth of the machined grooves. If found to be good they can hire 8th graders to put the good calipers back together.

Agreed...But it started out on the mechanical side with Hayes's incompetence. An initial bad run?....Hey, **** happens with all manufacturers. And it gets fixed. But the fixes aren't holding, THEN the complete replacements leaking?????? Been going on waaay too long. Yeah, I'd say "F's" earned all around on this one by both Hayes and BMW.
 
So my bike was inspected by two BMW engineers yesterday and also a NHTSA investigator, below is a email from the NHTSA investigator. These are the replacement Hayes calipers from the recall. I've had NO RESPONSE from BMW to any of my emails, amazing!!!!!!!

Steve,

We were able to view the inspection and they confirmed that both calipers were leaking. So now those parts are being sent to Germany for analysis to determine the exact origin(s) and they’ve agreed to update us regularly. They were going to get new calipers for your bike and double check them to confirm there’s no leakage before returning the bike to you.

I can also add that we had them check for any signs of other leaks in the system, all the way from the brake reservoir down to the calipers and the inspector indicated everything was dry. I also had him grip the brake firmly for an extended period to judge whether the leak was fast or slow and it must have been very slow because it didn’t get visibly worse in that short amount of time. He did note that the fluid in the sight glass was only about half way up, but I’m not sure how much fluid loss that represents.

BMW indicated they wanted to make sure the vehicle was checked and ridden by one of their techs to be certain of no leakage before returning it to you, so you may want to ask about what checks they did to ensure that. And of course let us know if you detect anything wrong.
 
I just got my bike back after the fifth time at the dealer and now have my third set of Hayes calipers in six months on my bike, not good. I'll let it sit for a few days to make sure there's no drips as recommended by the investigator at NHTSA.

Steve
 
What's worse is the 2021 models still have the Hayes calipers. So BMW has yet to learn their lesson. They went with a loser and their staying with it. German legendary stubbornness on full display. I could have told them to think long and hard before dropping Brembo for Hayes. Had Hayes brakes on all my 1990's era Harleys. A block of wood pressed against the tire would have worked better. It took a couple of decades, but Harley finally wised up and made the switch to Brembo calipers. Now BMW decides to go the other way and we all see the result (except BMW, apparently.). Dumb.
 
What's worse is the 2021 models still have the Hayes calipers. So BMW has yet to learn their lesson. They went with a loser and their staying with it. German legendary stubbornness on full display. I could have told them to think long and hard before dropping Brembo for Hayes. Had Hayes brakes on all my 1990's era Harleys. A block of wood pressed against the tire would have worked better. It took a couple of decades, but Harley finally wised up and made the switch to Brembo calipers. Now BMW decides to go the other way and we all see the result (except BMW, apparently.). Dumb.

It takes quite a while to make a change in a “finished product” supply chain. I really don’t think BMW is happy about all this whether it be a disappointed customer, bad press or the expense/trouble in remedying the problem.
I would put forth that if brakes from the ‘90s were not that great, but not stopping as they should, they may have under specs for the end product........ Was there a recall?
BMW has a pretty good warranty period. I don’t think they design in the hope to have to use it.

Some light reading-

https://www.bikebandit.com/blog/a-warranty-is-not-permission-to-thrash-your-bike

They all have problems- unfortunately.

OM
 
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