GS Exhaust & Exhaust Modifications FAQ
Please read the Disclaimer before attempting any work in this FAQ.
compiled by Kristian #562; edited by Scott, ID, #1244

For General Exhaust Questions (like discoloured Exhausts), refer the Classic Exhaust FAQ
Refer also the GS Performance Mods FAQ

General GS Exhaust Q's

For Exhaust Gasket Replacement, Cleaning etc. Refer the Classic Exhaust FAQ

Q: The Connection between the Two Parts of the Exhaust above the Rear Wheel Seems Loose/Leaks. I've noticed that the joint between the 2 rear silencers is loose and blowing slightly. Is this normal and would it explain the flat spot at around 3000rpm? Is the joint a simple compression joint or should it be spot welded?

A1. BMW doesn't want to fix this problem. They see that it happens on all of them so they don't fix. If you have any luck, post it here! I'll go back to my dealer. Chris
A2. This is just a slip fitting. No way to tighten and no need to. It will not hurt anything. This is indeed the way they are supposed to be. Some leak more than others but not to worry. Stuportech

Q. Any Exhaust Modifications on the GS?
A. See the GS Performance Mods FAQ or go directly to the Exhaust Modifications GS FAQ,

Q. Does anyone know why the first (left) silencer has a small hole and has a visible exhaust flow while the second in line (right) has a big hole and seems to have no gas coming out? Just something I noticed on the off road course.
A. The small hole serves as kind of an equalizer, forcing some of the exhaust to go to the right muffler. Actually, exhaust does exit through both mufflers. RogerN #827

Thanks to Trevor #999 for the following:

Q. Glowing Exhaust header Pipe?
A. Might be you need an FI reset. See Why is my Exhaust Glowing?

What's available (As Aftermarket)


Laser (Omex) Remus- This Photo shows the OEM Luggage Rack but there has been a reported case of  possible trouble fitting the OEM cases on the Rack. You should check with your Dealer. Sebring Staintune Two Brothers



If your Pipe looks like this, it was the Adventure Pipe I - Now Superseded

Adventure Pipe II

Adventure Pipe Right Side Storage Canister

Adventure Pipe Right Side Storage Canister

Universal Right-Side Storage Canister for the BMW F650GS/DAKAR. Includes integrated key-lock.

Adventure Pipe for 650CS



Ross Brisbane Australia (Faux Exhaust Storage Container)

SCX Staintune with Faux Storage Container


SCX Sebring Dual Pipes


Stock Exhaust Modifications

Removal of the GS exhaust baffle from the muffler (Note this is NOT the same as the Catalytic Converter)
by Rocket boy

For a GS it's pretty simple, to get the sound and performance out of it with out destroying it.

by Kevin #1092

Pics kindly supplied by Kevin #1092

Q. After reading the FAQ info about removing the exhaust baffle, I had at it. The FAQ suggested that it was just some sorta press-fit arrangement. Mine was not -- it was spot-welded in via two little tabs which broke off when I cranked on it. It most assuredly WILL NOT go back in now.
A. You did it right. If I remember correctly there were two more welds inside. Take that whole straw thing out and it is done. Brad in SB #979.

For Feedback on the Baffle Mod, see Stock Exhaust below.

Storing your OEM Exhaust

Q. I'm about to install a new Staintune to my 01 Dakar. I will need to keep the stock exhaust for the UK MOT (annual legality and roadworthiness check - first one in two years time). Would I be correct in thinking that all the nasty chemicals which rot exhausts from the inside will still be active in the stock exhaust whilst in storage. And if so how best can I protect it ? I don't really want to fill/flush it out with oil - there is an emission test as part of the MOT ! So I'm leaning more towards a good flush out with water. Any advice, thanks.

A. Stock is stainless steel and will never corrode. No worries. Flash #412
A. I would get a heavy duty garbage bag, find some moisture absorbing substance to throw in and bag it up if you have any worries. You could dry it out by leaving it out in the sun first, unless of course the sun never comes out where you are. Chris in Santa Cruz, CA #782


Note: Many Opinions on essentially the same pipe in the Classic Exhaust Mods FAQ


Air Filter Mods

Adventure Pipe





Stock Exhaust Modifications

Two Brothers

Loud Pipes (e.g. D&D)

Exhaust Cut-Outs?


Q. I've heard of an exhaust valve that you can install that will make your exhaust sound normal when driving sensibly but when you open it up the pressure from the exhaust opens it up and lets the exhaust out early before the muffler. It's like a 2 way pipe with a valve in the middle. It's to stop the cops pulling you over but when you want the noise it'll be there. I want to know the name of the product and who makes it?

A. It is called an exhaust cut-out. Here's how it works. (Flash#412)



What to do with the Space when one Exhaust is removed:


Will I need to modify the Chip if I add an Aftermarket Exhaust?

by Rod CO '02GSA


With regards to FI bikes and effects of changing the intake or exhaust, I've done extensive investigation and testing on the F650GS. The FI system will automatically adjust to exhaust/intake changes to a certain point. I would ensure the manufacturer can provide Dyno test results that show HP/RPM curves are close to the original exhaust set-up (perhaps slightly more HP). If the bike idles normally, doesn't smoke, fuel consumption doesn't change substantially, and the color of the spark plug electrode is normal, then the FI system is adjusting to the new intake/exhaust adequately. A gas analyzer right in the header at the oxygen sensor would tell you the same thing. When you remove the stock right-side catalytic converter and muffler assembly and look down the header-end, you will see how restrictive the catalytic converter really is. Just by removing the cat you will feel an improvement. BMW claims the F650GS is the first single cylinder 650cc bike with a cat, and perhaps it should not have been. Hope this helps calm your hesitation on aftermarket exhaust. I would be very surprised if exhausts on the market did not work well.