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Just out of interest I disabled the exhaust flap valve (the one the opens/closes) with throttle variation.
There are many opinions on what this does, if its necessary and so on. In addition to a friend of mine who was a official ktm and bmw mechanic stated that it optimised the release of the engine gasses for the stock exhaust system.

My reason for tampering with it was to get a bit more volume from the bike given the valve is now in the open position. Did this by unhooking the cables from the flapper valve. Leaving everything else as is. If you unplug the servo moro, the bike will register a fault (apparently there is a plug in gadget for this)

Result: Volume on start and riding at lower speeds the bike is noticeably louder. I haven't noticed any differences in power or performance. Easy to do, and easy to put back to stock.
 

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I did this a while ago, but decided that (with my SC Project end can) I preferred a slightly quieter tickover, so reinstated it. Like you I notice more noise at idle and on part throttle and no noticeable chages to performance. It's only a five minute job so easy if you fancy giving it a try...
 

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I can't say with any authority why BMW installed this valve, but I do know that Star brand (Yamaha, I think), use a similar valve in their v-twin cruisers to increase low-end torque. Some Harley riders, often riding bikes with drag pipes, will add torque-cones to increase low-end torque. Maybe this is what BMW had in mind.

I have talked to Star owners who said that removing the valve killed low-end power and made the exhaust louder.

BMW did an extraordinary job of configuring the engine/fly-by-wire throttle on the 2015 R1200R. I have never ridden another motorcycle that had a smoother, more predictable throttle. The power curve is so linear that one would think that it was an electric motor. Harley tried this with their Twin-Cam motors and it was a major failure from the perspectives of both reliability and throttle control. BMW got fly-by-wire throttle as right as it can get.

Pete


Just out of interest I disabled the exhaust flap valve (the one the opens/closes) with throttle variation.
There are many opinions on what this does, if its necessary and so on. In addition to a friend of mine who was a official ktm and bmw mechanic stated that it optimised the release of the engine gasses for the stock exhaust system.

My reason for tampering with it was to get a bit more volume from the bike given the valve is now in the open position. Did this by unhooking the cables from the flapper valve. Leaving everything else as is. If you unplug the servo moro, the bike will register a fault (apparently there is a plug in gadget for this)

Result: Volume on start and riding at lower speeds the bike is noticeably louder. I haven't noticed any differences in power or performance. Easy to do, and easy to put back to stock.
 

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Totally agree with Pete. I've ridden a lot of bikes in my 44yrs riding; the ride-by-wire\fuel injection is the smoothest and most progressive that I've experienced. My previous bike was a Ducati Monster 1100evo, beautiful but piss-poor fueling even after re-mapping and lowered gearing. Great if you were in a hurry but hopeless under 3,500 revs. Test rode a new 1200 Monster that was nearly as bad, Diavel was better. Loving my 2016 R with an Arrow can; best bike I've ever owned.
 

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When I first started looking seriously at R1200R's it was in 2015. Knowing the specs on the bike, I expected the throttle to be a handful - no low-end torque, narrow power band, and overall a real pain to ride. I figured that after a test ride that I would just get back on my Harley and never think about a BMW again. I could not have been more wrong. My 2015 R1200R has plenty of low-end torque - not as much as my Harley, but we are comparing a modern motorcycle motor to a tractor motor. It took a little while for me to adjust to adding a little extra throttle on the R1200R when I took off from a stop, and I do mean a little.

One moving, the throttle on the R1200R is so much better than on a Harley. The power curve seems to go on forever without any noticeable flat spots. Low-speed riding - parking lots, traffic, gas stations, is much easier on the BMW than it is on a Harley.

Pete

Totally agree with Pete. I've ridden a lot of bikes in my 44yrs riding; the ride-by-wire\fuel injection is the smoothest and most progressive that I've experienced. My previous bike was a Ducati Monster 1100evo, beautiful but piss-poor fueling even after re-mapping and lowered gearing. Great if you were in a hurry but hopeless under 3,500 revs. Test rode a new 1200 Monster that was nearly as bad, Diavel was better. Loving my 2016 R with an Arrow can; best bike I've ever owned.
 

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Throttle is spot on ...linear -predicatable-easiily managed whether in Dynamic(immediate throttle) or Road Mode(softer throttle)-what a motor-not doing anything to it -its right - "right out of the box".
 

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When I first started looking seriously at R1200R's it was in 2015. Knowing the specs on the bike, I expected the throttle to be a handful - no low-end torque, narrow power band, and overall a real pain to ride. I figured that after a test ride that I would just get back on my Harley and never think about a BMW again. I could not have been more wrong. My 2015 R1200R has plenty of low-end torque - not as much as my Harley, but we are comparing a modern motorcycle motor to a tractor motor. It took a little while for me to adjust to adding a little extra throttle on the R1200R when I took off from a stop, and I do mean a little.

One moving, the throttle on the R1200R is so much better than on a Harley. The power curve seems to go on forever without any noticeable flat spots. Low-speed riding - parking lots, traffic, gas stations, is much easier on the BMW than it is on a Harley.

Pete
Don't get me started on Harley v BMW R12R! I've had a Road-King for 15yrs. I love it, but it's from a different biking era and philosophy. No comparison really.
 

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I have both the R1200R (2015), and the HD Ultra Limited. They serve two different purposes for me. I use the HD when my wife and dog wants to come along with me, or when I want to go slow, listen to music and just ride. My wife finds the HD the most comfortable bike I owned (I've owned 10 bikes so far). The BMW is when I have the need for speed and fun. Technology wise, yes day and night, but that's never been the primary deciding factor for me.
 

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Juuce and others: I've been reading the threads regarding disabling the flapper valve and I believe I'd like to give it a try. What exactly did you do to disable the servo and/or valve? I noticed that on some other (older?) BMW models, that the valve can be simply removed from the exhaust pipe by loosening clamps and then by replacing with a section of stainless steel tubing, but my 2016 R12R seems to have the assembly welded to the end of the exhaust pipe. Short of investing a king's ransom on a whole new system, I'd like to check out the sound difference made by disabling the flapper valve. Thanks!
 

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THE PURPOSE OF THE IS VALVE TO MAINTAIN OPTIMUM OPERATING TEMPERATURE IN THE CATALYTIC CONVERTER.
If you choose to remove it, you are contributing to the death of the planet and compromising my grand-kids' future (I removed mine because it is a right old dirt trap and a proper kerfuffle to clean around)
 

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Juuce and others: I've been reading the threads regarding disabling the flapper valve and I believe I'd like to give it a try. What exactly did you do to disable the servo and/or valve? I noticed that on some other (older?) BMW models, that the valve can be simply removed from the exhaust pipe by loosening clamps and then by replacing with a section of stainless steel tubing, but my 2016 R12R seems to have the assembly welded to the end of the exhaust pipe. Short of investing a king's ransom on a whole new system, I'd like to check out the sound difference made by disabling the flapper valve. Thanks!
To disable, simply remove the heat shield, then the plastic cover over the valve. The cables may then be detached from the pulley.

They'll flap around a bit inside the cover, so if you decide to leave it that way, I would also suggest detaching them from the servo end. To do this, unclip the O2 sensor lead and the valve lead, remove the attachment screws, and swing the servo unit out. Remove the screws that hold it together, detach the cables, then feed both of them fully towards the valve so that the nipples don't foul the pulley.

The ECU will register an exhaust butterfly calibration error each time the bike is run, but this is innocuous - it doesn't display on the instrument panel and instances aren't cumulative within the computer.

Not sure about the theory that the valve keeps the Cat at optimum temperature.

[Edit - the torque of the geared down stepper motor is very high and will eventually break one of the internal stops of the stepper motor gearbox. A Servo Buddy or similar is highly recommended]
 

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Just a correction (I was going from memory ...) - no need to remove the heat shield.
 
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