I deleted my RT with a BlackWidow performance stainless header, no regrets.
Exhaust Servo Motor Failure
Hey guys,
I noticed a couple months ago that my exhaust flap wasn't working. I assumed it was going to be a seized flapper valve and planned to work it free when I got a chance. Today, I pulled the silencer off to have a look. I could move the flapper very slightly, but not much. I turned on the ignition to attempt the self-test, nothing happens. I connected with my GS-911 and ran the exhaust flap test. The Hex software told me that the output actuation completed successfully, but still no movement on the flapper. I removed the cables from the valve going to the servo motor. I tried rotating the flap, and to my surprise, it rotated completely free. I can spin it all the way closed with zero effort, and when I release it, it snaps back. I turned on the ignition again to see if I'd get any movement from the servo motor with it disconnected, nothing. Next, I pulled the servo unit from the bike and opened it up. I tried rotating the pulley inside of the servo unit with all my might, no movement. I'm not sure if this should be able to spin by hand or not...
Anyways, it sounds like my servo motor is shot. Would you guys agree? The only other thing I can think of trying is to find a wiring diagram and make sure I have voltage at the plug. Not sure if this is worth doing or not. I'm not even sure where to find a wiring diagram, can anyone point me in the right direction? I'll take a look in the service manual to see if I can find anything.
According to Healtech and multiple sources online, "the exhaust flap valve is designed to improve low down torque with the hindering of the flow of escaping gasses creating back pressure in the exhaust system". Even Akrapovic is putting valves on their headers for the R1250RT now. They say it is for improved rideability in lower RPM. I've read of many people removing these on their Wetheads and noting that they noticed no difference in performance. Many claim it is just for noise reduction. I ran a Servo Eliminator on my previous Ducati and had no issues. Thoughts?
It looks like the servo motor is around 300USD brand new. The only one I was able to find on eBay will cost around 250USD with shipping to Canada. Healtech makes a Servo Eliminator for our bikes and it's worth about 60USD.
I noticed a couple months ago that my exhaust flap wasn't working. I assumed it was going to be a seized flapper valve and planned to work it free when I got a chance. Today, I pulled the silencer off to have a look. I could move the flapper very slightly, but not much. I turned on the ignition to attempt the self-test, nothing happens. I connected with my GS-911 and ran the exhaust flap test. The Hex software told me that the output actuation completed successfully, but still no movement on the flapper. I removed the cables from the valve going to the servo motor. I tried rotating the flap, and to my surprise, it rotated completely free. I can spin it all the way closed with zero effort, and when I release it, it snaps back. I turned on the ignition again to see if I'd get any movement from the servo motor with it disconnected, nothing. Next, I pulled the servo unit from the bike and opened it up. I tried rotating the pulley inside of the servo unit with all my might, no movement. I'm not sure if this should be able to spin by hand or not...
Anyways, it sounds like my servo motor is shot. Would you guys agree? The only other thing I can think of trying is to find a wiring diagram and make sure I have voltage at the plug. Not sure if this is worth doing or not. I'm not even sure where to find a wiring diagram, can anyone point me in the right direction? I'll take a look in the service manual to see if I can find anything.
According to Healtech and multiple sources online, "the exhaust flap valve is designed to improve low down torque with the hindering of the flow of escaping gasses creating back pressure in the exhaust system". Even Akrapovic is putting valves on their headers for the R1250RT now. They say it is for improved rideability in lower RPM. I've read of many people removing these on their Wetheads and noting that they noticed no difference in performance. Many claim it is just for noise reduction. I ran a Servo Eliminator on my previous Ducati and had no issues. Thoughts?
It looks like the servo motor is around 300USD brand new. The only one I was able to find on eBay will cost around 250USD with shipping to Canada. Healtech makes a Servo Eliminator for our bikes and it's worth about 60USD.
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You never noticed a performance issue as I assume you were driving it this way for a bit and it doesn’t throw an error. Why do you need a servo eliminator then?
Yeah, good point. I guess I'd just rather remove the broken servo than leave it in place. I would replace it if I could find a decent deal on one.You never noticed a performance issue as I assume you were driving it this way for a bit and it doesn’t throw an error. Why do you need a servo eliminator then?
I am in the noise camp after doing loads of research. On the 1250 if the flap or servo fails you normally get an orange warning light. Therefore you then need to cancel it with a GS 911. Think if it was me, I'd buy a servo body and leave the flap in the open position. I never experienced any performance issue with the flap not working on my 1250 and I have a flap on a 62k RTp that hasn't worked correctly for years and found no issues.
That's the weird part, I don't have any warning lights. When I scan with the GS-911, I don't have any related faults.I am in the noise camp after doing loads of research. On the 1250 if the flap or servo fails you normally get an orange warning light. Therefore you then need to cancel it with a GS 911. Think if it was me, I'd buy a servo body and leave the flap in the open position. I never experienced any performance issue with the flap not working on my 1250 and I have a flap on a 62k RTp that hasn't worked correctly for years and found no issues.
I had my exhaust manifold and flapper valve replaced by BMW under warranty when the original failed. I don't think the later valves do the 'self test' where they cycle upon ignition switch on. Mine is a 2019 R1250 RT. Cheers....
Hmm, interesting. It's weird that I didn't see it move when I did the exhaust flap test with the GS911. Can anyone with a 2019+ confirm their valve doesn't do the flap test? Any way to see it operate? It doesn't move when I start the engine...I had my exhaust manifold and flapper valve replaced by BMW under warranty when the original failed. I don't think the later valves do the 'self test' where they cycle upon ignition switch on. Mine is a 2019 R1250 RT. Cheers....
Beemer Boneyard maybe?I would replace it if I could find a decent deal on one.
I'll check it out. I want to be 100% sure it is actually failed before I buy one. I didn't know the new bikes stopped doing the self-test with the ignition on. When I run the engine, I should see it close partially? It doesn't move. Maybe I should give it some throttle and look at it...Beemer Boneyard maybe?
Also suspect is that I get no movement on the valve when performing the exhaust flap check on the GS911. It's weird that I'm not getting a code or warning light for this...
UPDATE:
It seems my problem is resolved, but I don't understand why. I decided to hook the partially disassembled servo unit back up to the bike today to try it again. To my surprise, as soon as I turned on the ignition, the internal pulley rotated back and forth. This is the part I'm talking about:
![Camera accessory Auto part Fashion accessory Metal Engineering]()
I tried this yesterday before removing the servo unit from the bike and it did not work. I reassembled the cables inside of the servo and put it back together:
![Automotive tire Wood Bag Electric blue Luggage and bags]()
I installed it back on the bike and reattached the opposite ends of the cables to the exhaust valve:
![Automotive tire Motor vehicle Automotive lighting Automotive design Vehicle brake]()
It is now functioning. It successfully does a self-test with every ignition-on cycle. So what is going on here? I don't understand why opening it up and putting it back together has solved my issue. I'm happy it works now but very confused as to why it wasn't working in the first place...
It seems my problem is resolved, but I don't understand why. I decided to hook the partially disassembled servo unit back up to the bike today to try it again. To my surprise, as soon as I turned on the ignition, the internal pulley rotated back and forth. This is the part I'm talking about:
I tried this yesterday before removing the servo unit from the bike and it did not work. I reassembled the cables inside of the servo and put it back together:
I installed it back on the bike and reattached the opposite ends of the cables to the exhaust valve:
It is now functioning. It successfully does a self-test with every ignition-on cycle. So what is going on here? I don't understand why opening it up and putting it back together has solved my issue. I'm happy it works now but very confused as to why it wasn't working in the first place...
In the service we called it "FM". Thanks for the story. May save me some money down the road.
I’ve had the yellow engine fault warning come up a couple of times of late on my 2021 R1250RT which I assume will be the start of my exhaust valve sticking (coupled with not hearing the motor move on start up and after about a minute of turning off the ignition). I’ve logged it with my dealer as I’m due a service in a couple of weeks and the bike is still under warranty. Obviously they haven’t seen the bike yet or downloaded the faults, but they also suspect that it’s the exhaust valve sticking.
Interestingly though, they tell me that there is a BMW modification to the exhaust valve that was apparently released midway through 2021. I can‘t find any other announcement of this modification but they assure me that out of the bikes they have modified, none have had the problem return. Anybody know of the modification ?
Interestingly though, they tell me that there is a BMW modification to the exhaust valve that was apparently released midway through 2021. I can‘t find any other announcement of this modification but they assure me that out of the bikes they have modified, none have had the problem return. Anybody know of the modification ?
In the aerospace biz we refer to it as "PFM" where P = "Pure".In the service we called it "FM".
Also referred to the theory of flight. How can something so heavy get off the ground? 🤔🤣In the aerospace biz we refer to it as "PFM" where P = "Pure".
I like thatIn the service we called it "FM". Thanks for the story. May save me some money down the road.
Since you had no mechanical faults discovered with any of the components, that leaves the only thing you moved while playing with the assembly: the connector. It is the most plausible explanation. Unplug/replug often has that effect if there was some crap caught in there or water got in and begun the corrosion process.So what is going on here?
My flapper valve is stuck and engine warning light is on. When I opened it up to see if there was any movement on turning on ignition, some times it tries to move and other times it doesn't. According to BMW Motorrad, mine has had two replacements already. Not good if it costs £1500 a time.Hmm, interesting. It's weird that I didn't see it move when I did the exhaust flap test with the GS911. Can anyone with a 2019+ confirm their valve doesn't do the flap test? Any way to see it operate? It doesn't move when I start the engine...
Well if it was me I would put a set of headers on and be done.My flapper valve is stuck and engine warning light is on. When I opened it up to see if there was any movement on turning on ignition, some times it tries to move and other times it doesn't. According to BMW Motorrad, mine has had two replacements already. Not good if it costs £1500 a time.
I use Akrapovic headers and do not miss the flap at all. It's whole function is noise abatement and nothing more. You can buy a Servo Buddy and that takes care of the dash light when not having that mess on your exhaust.
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