BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

A search turned up this topic about removing the muffler (semi-permanently) over in the R1150R forum:

http://tinyurl.com/3ok8ds

Having given up on my exhaust cutout idea and still wanting to try for some more authoritative exhaust note, I thought I'd give it a try.

Muffler comes off very easily: 15mm wrench to remove the clamp at the cat converter end and a T45 bit to remove the hanger screw at the passenger foot peg end. Then a lot of gentle wiggling-whilst-tugging and voila: 10 lbs of metal ended up cradled in my arms. Tip: Don't tug so hard you pull the bike off the center stand

I had previously removed the muffler several times to remove the rear wheel. I know you're supposed to be able to remove the wheel with the muffler in place, but I tried to no avail. Maybe because I have the chrome muffler option? Tip: apply some high-temp anti-seize goop to the cat stub and the muffler comes off easier next time.

A trip to my local muffler custom shop and we ended up putting a 2 1/4" section of pipe on. Its end had to be expanded to fit. Then we slitted it so the stock clamp could hold it in place. A little deburring stopped me from further lacerating my fingers. A chrome slant-end extender slipped over it perfectly.

Pic: http://tinyurl.com/3scfx6

I used a 3/8 x 3/4" hex head cap screw with a chrome acorn nut and lock washer to both hold the chrome sleeve in place and serve as a stop for the rubber foot on the center stand.

Pic: http://tinyurl.com/3fb2hg

To my ear the engine now produces a very nice rumble at idle, not too loud under gentle acceleration, and only slightly obnoxious under heave acceleration. The best part, for my purposes, is that it's fairly loud when blipping the throttle with the clutch in, so I can get a little respect when lane-splitting in stalled traffic on the freeways. It's certainly lost the sewing machine character!

No, I don't think loud pipes save lives and I definitely don't have HD envy. But it's nice to have a machine that actually sounds like a motorcycle. For now, it's great pretending to be a hooligan. Heck a pretty young woman even turned to look at the bike as I came down the street; then she saw my face. Oh well...

I may well tire of the sound and re-install the stock can, especially for long trips.It's nice that it's a 5-minute job.

If anyone's curious what this sounds like, just remove your muffler, and start 'er up. I don't recommend running very long without a tip, because it will probably throw carbon on your rear tire and maybe even cook it a bit.

Several posters in the 1150 forum say it won't hurt the engine and some have cited dealer mechanics that have agreed. I do notice a bit of backfiring upon deceleration in about the 3000-4000 range. If anyone knows of risks this modification might incur, I'd sure like to know soon!

Market survey: Do you folks think some R1200R owners would be interested in purchasing a ready-made polished stainless steel version, with the acorn nut stop, for about $50? I proposed the idea to the very helpful owner of a local muffler shop and he seemed open to providing this service. If any forum members are interested, send me a message and I'll report back if and when he starts production.

...and just when I thought you couldn't do anymore to your bike.

Cool mod.
I'd love to hear what it sounds like, but I won't be taking my muffler off anytime soon. I actually like the looks of the big bazooka on the side.

Is nothing sacred?
Mark

Funny - this AM I must have been in more of a daze then usual.. I forgot to put my earplugs in before I took off for work. Got about 50 feet and realized it, but decided I'd do it further down the road. By the time I got further down the road I decided I was enjoying the noises this bike makes.. so I ended up never putting them in for my 16 mile ride to work (which includes local, small state and interstate highways).

It was quite enjoyable. The stock muffler has a very nice little growl to it that I could make happen on demand (I noticed my fuel mileage dipped down into the 30's.. ) I don't think I'd want anything louder than what I have since it would make me use too much fuel.. just listening to the sound.

If you haven't tried your R12R without earplugs - give it a short ride. Wonderful mechanical noises combined with a slght growl..

I ran my 1150R with no muffler for quite some time, liking the sound...
Haven't heard the 1200R with it off.... I find the sound with the OEM muffler to be good enough for me, and haven't tried it.
Would like to hear it though...

.....what was a little funny to me that when you read the other tread to the very end....most of the people that were raving about not having the silencer ended up putting it back on......but....to each it's own:-)......I just ordered Akrapovic and planning to take the baffles out......should give me a nice rumble

Graf wrote:.....what was a little funny to me that when you read the other tread to the very end....most of the people that were raving about not having the silencer ended up putting it back on......but....to each it's own:-)......I just ordered Akrapovic and planning to take the baffles out......should give me a nice rumble

Yes, noticed that trend also.

Update: Yesterday was my first time splitting lanes in Monday morning rush hour traffic into San Francisco on the 101 freeway, sans silencer. A couple of times cars were right on the braille stripes and I couldn't get through. Instead of my usual stopping and waiting patiently, I stopped and blipped my throttle a couple of times and, lo and behold, the sea of cars parted and I was able to continue on. So it actually works for my intended purpose. I gave them a "Thank You" wave, to help maintain biker/car relations.

What I don't like, and what will probably lead to my joining the ranks of those who put the stocker back on, is that on those few times when I feel I need to accelerate rapidly at an intersection in a quiet neighborhood, it's pretty darned loud. That's why I originally thought of using a cutout.

An unforeseen consequence of removing the muffler: I tend to be much more gentle on the throttle now, since, under conservative acceleration, the sound level is a pleasant rumble. That should save some gas and make my tires last longer.

Interesting. I know BMW 's run pretty quiet like sewing machines, but I would like to hear a bit more rumble from the exhaust....not sure if I want to completely remove the muffler though.

I really enjoyed the throaty rumble of my Sportster's exhaust. I am enjoying even more the underplayed growl of my stock R12R.

As soon as I got my roadster in January I knew I would eventually change the exhaust in order to give it a sound more in character with the bike. After reading Bay Area Bill's post and wading through the 9 pages of the R1150R forum thread, I decided to jump in. Not much to lose... I could always reinstall the original can or move on to an aftermarket piece. A quick trip to Auto Zone for parts and about an hour of wrenching and hacking resulted in this...




The parts purchased were a curved exhaust tip, 2.25" OD, and an adaptor sleeve to go over the 2.25" pipe coming off the cat converter and into the tip. I cut (hacked) two slots in the adaptor in order to use the original clamp to attach to the cat, drilled two holes in the adaptor to receive the screws from the tip, and mounted a bolt with an acorn nut (thanks for the idea, Bill) on the tip as a center stand stop.



As soon as I removed the can I started it up, of course, and thought it sounded maybe too loud and a little coarse and flat. After installing the tip, though, it seemed to mellow out a little. So it was time for a road test.

Today I took a 50 mile ride that included city streets, 8 lane thundering freeways, and some of my favorite local mountain roads. I'd tell you where those are, but I'd have to kill you. Started out without earplugs and stayed on city streets. On the road it is not at all too loud, at least to my ears. At one point I passed a couple of Harleys with straight pipes going the other way and they completely overwhelmed any sound coming from my bike. At WOT, it does turn heads. But at normal RPMs and shift points, the volume is, IMHO, very reasonable and the quality is pleasing to my ears. With my Shure earbuds in, the exhaust sound was a pleasing background rumble that only enhanced the MP3 sound track and complemented the mild boxer vibration.

As for differences in performance, nothing huge. Less weight, of course, which is always welcome. No sense of out-of-balance by not having a can hanging off the left side. If anything, the reduced mass was welcome in the twisties. But, it may only be my imagination, the torque curve seems to have changed (I have no comments as to high RPM power, because I usually don't go there), and I can only describe it this way: There is an 11 mile stretch of winding mountain road that, before surgery, I would navigate mostly in 3rd gear, as it was needed for adequate acceleration out of corners, but resulted in too much compression braking while setting up for corners. Today, I rode the same road mostly in 4th. The higher gear - 4, 5 and 6 - roll-on seems noticeably stronger and the compression braking in 4th was perfect for setting up corners. Bottom line, I went through the route both smoother and faster. There are many folks who contribute to this forum who may be able to theorize why the torque curve is different, but that's not me. For now, I plan to leave the pipe as-is.

Just curious - in the Harley world, when you put on a different muffler, you have to pay the dealer to reprogram the engine control unit (for FI bikes), because the change in backpressure throws off the fuel mixture needed (or something like that). Do the BMW ECUs automatically adjust for removing or changing the muffler?

Dr Grabow wrote:Just curious - in the Harley world, when you put on a different muffler, you have to pay the dealer to reprogram the engine control unit (for FI bikes), because the change in backpressure throws off the fuel mixture needed (or something like that). Do the BMW ECUs automatically adjust for removing or changing the muffler?

The R1200# series bikes continually adjust the mixture based on the two O2 sensors - one for each cylinder, and the knock sensors - one for each cylinder. There are no alternate programs available for the BMW bikes AFAIK.

While were on mufflers.
Has anyone tried running a drill through the baffles on the stock muffler. I have no idea what the inside looks like and naturally the downside would be their would be no going back.

deilenberger wrote: The R1200# series bikes continually adjust the mixture based on the two O2 sensors - one for each cylinder, and the knock sensors - one for each cylinder. There are no alternate programs available for the BMW bikes AFAIK.

Awesome. Looks like a little experimenting is in order. Thanks for the answer.

Found this topic just in time. Going to ride with some buddies in the Thunder Run tomorrow. Harley guys for the most part, and I was told my beamer needed some more rumble if I was going to run with them. Well, the short of it is that I removed the OEM can and bought a $25 tip at Pep Boys (just to dress it up a bit). Sound is great, and looks clean. Probably going to keep it. Great forum, thanks!!!

Nice post Ron.
Do you have a picture of the whole bike without the exhaust?

Thanks

Here it is...Other lost parts include the airfoils from the fork, the R1200R decals on the tank (making this the fastest Black of all ), the license bracket reflector ears, the charcoal canister and all associated plumbing, the fork reflectors, and of course the MM ear mirrors, proving yet again that less is more:

Very clean Ron. Any engine cooling issues from removing the fork fins? I believe they're suppose to direct airflow to the oilcooler?

Interesting, but... no way to do anything like this in Italy,

Here officiers are very concerned about bike's noise... Doing this could results in heavy ticket, bike's documents seizing then bike examination (expensive) after having reinstalled an approved muffler.

tobes wrote:Very clean Ron. Any engine cooling issues from removing the fork fins? I believe they're suppose to direct airflow to the oilcooler?

No effect that I have seen so far, including high speed runs through the mountains and moderate speed, freeway lane-splitting slogs through traffic in 85F temperatures. Of course, the fins would not provide relief from low speed/high temp conditions. I have seen one aftermarket carbon fiber front mudguard without fins in a European catalog. The accompanying blurb claimed that the fins serve no real purpose. My experience is consistent with that; the temperature gauge is locked in at the lower end of the normal operating range.