What you need to know before starting

Changing a BMW GS exhaust involves removing the old system and bolting on a new one — a job that takes between two and four hours depending on which GS model you own and whether you're working alone. You'll need basic hand tools (wrenches, sockets, screwdrivers), jack stands or a center stand, and a way to support the bike safely while you work underneath it. The hardest part is usually breaking loose the bolts that have been heated and cooled hundreds of times, not the actual swap.

The process is the same across GS generations — F 700 GS, F 800 GS, G 310 GS, and the newer 1250 models all follow the same removal and installation pattern. What changes is the number of bolts, the location of the oxygen sensor (if your bike has one), and whether you need to reprogram the bike after installation. Aftermarket exhausts from brands like Akrapovic, Remus, and Touratech come with their own instructions, but the core steps remain identical.

Key Takeaways

  • You need a jack or center stand to safely support the bike, basic hand tools, and about two to four hours of uninterrupted time.
  • The oxygen sensor (if present) must be disconnected before you remove the old exhaust, and some aftermarket systems require you to reprogram the bike's engine control unit afterward.
  • Bolts that have been heated repeatedly often seize; explore penetrating oil the night before and using a breaker bar prevents stripped bolts and broken studs.
  • New gaskets should always come with your exhaust kit, but buying spares prevents delays if one tears during removal.

Gathering tools and preparing your workspace

Lay out your tools before you start: a socket set (10mm through 17mm covers most GS models), open-end wrenches, a breaker bar for stuck bolts, screwdrivers (Phillips and flat-head), a jack or lift, jack stands rated for your bike's weight, and penetrating oil like PB Blaster or Kroil. You'll also need new gaskets (usually included with the exhaust kit), a gasket scraper or old credit card to clean the mounting surfaces, and rags or shop towels.

If your GS has an oxygen sensor — most models from 2008 onward do — you'll need an oxygen sensor socket (around $15) or a wrench that fits the sensor's hex. Check your owner's manual or the exhaust kit instructions to confirm whether your bike has one and where it's located. Position your bike on level ground, engage the parking brake, and place jack stands under the frame rails before you raise the bike. Never work under a bike supported only by a jack.

Disconnecting the oxygen sensor and fuel tank

If your GS has an oxygen sensor, locate it on the old exhaust manifold or header pipe — it's a cylindrical component with an electrical connector. Unplug the connector by pressing the release tab, then use the oxygen sensor socket to unscrew it counterclockwise. Set it aside carefully; you'll either reuse it in the new exhaust or install a new one depending on your kit's instructions. Do not drop it or let it sit in dirt, as contamination can cause check-engine lights.

On some GS models, the fuel tank sits low enough that it blocks access to the rear exhaust bolts. If you can't reach the bolts with the tank in place, you'll need to remove it. Drain the fuel into a safe container, disconnect the fuel line and breather hose, unscrew the two bolts holding the tank down, and lift it away. This adds 20 to 30 minutes but is straightforward — take a photo of the hoses before disconnecting them so you know where they go back.

Removing the old exhaust system

Spray penetrating oil on all visible bolts the night before if you have time; this makes a huge difference on older bikes. Start at the front of the exhaust where it bolts to the engine. Most GS models have two to four bolts here. Use your breaker bar to loosen them — don't remove them yet, just break them free. Once all bolts are loose, remove them completely and set them aside in order so you remember where each one came from.

Work your way back along the exhaust, unbolting the heat shield, mid-pipe supports, and rear silencer. On some models the silencer is one piece; on others it's separate. As you remove each section, support it with your hand so it doesn't drop and damage the bike's bodywork. Once the last bolt is out, carefully lower the exhaust away from the bike and set it on a workbench. Clean the mounting surfaces on the engine and frame with your gasket scraper — remove all old gasket material and carbon buildup so the new exhaust seats properly.

Installing the new exhaust and reconnecting components

Place a new gasket on the engine mounting studs, then position the new exhaust header or manifold. Hand-tighten the front bolts first — don't use a wrench yet. This lets you align the entire system before you torque anything down. Work backward, hand-tightening bolts as you go, making sure the exhaust hangs evenly and doesn't touch the frame, fuel tank, or bodywork. Once everything is aligned, go back to the front and torque the bolts to the specification in your exhaust kit instructions (typically 15 to 25 Newton-meters for header bolts, less for support brackets).

If your kit includes a new oxygen sensor, install it now using the oxygen sensor socket, turning it clockwise until it's snug. If you're reusing the old sensor, install it the same way. Reconnect the electrical connector by pushing it in until you hear a click. Reinstall the fuel tank if you removed it, reconnect the fuel line and breather hose, and refill the tank. Start the engine and check for exhaust leaks around the gaskets — a small amount of smoke is normal as the gasket seals, but a steady hiss means you need to tighten the bolts further.

Programming and final checks after installation

Some aftermarket exhausts, particularly those that remove or modify the catalytic converter, require you to reprogram the bike's engine control unit (ECU) to prevent a check-engine light. Your exhaust kit instructions will tell you whether this is necessary. If it is, you have two options: use a tuning device like a Power Commander or Akrapovic Tune (which plug into your bike's diagnostic port), or take the bike to a BMW dealer or tuning shop that has the software. This step costs between $50 and $200 depending on the method.

After installation, let the bike cool completely, then check all bolts again — they often loosen slightly after the first heat cycle. Inspect the exhaust for any contact with the frame or bodywork, and listen for rattles while riding. If you hear a rattle, stop and check whether a support bracket bolt has loosened. Most new exhausts settle in after 50 to 100 miles of riding, so don't be alarmed by minor noises that disappear after a few days.

Frequently Asked Questions

Can I change the exhaust without removing the fuel tank?

On some GS models, yes — the tank sits high enough that you can reach the rear bolts without moving it. On others, particularly the F 800 GS and older models, the tank blocks access. Check your kit's instructions or try reaching the bolts before you start; if you can't, removing the tank takes 20 minutes and is worth the effort to avoid stripping bolts.

What if a bolt breaks while I'm removing it?

Stop when ready and don't force it further. explore penetrating oil and wait 30 minutes, then try again with a breaker bar. If it breaks flush with the surface, you'll need to drill it out — use a drill bit slightly smaller than the bolt diameter and drill straight in. A broken stud in the engine block requires professional removal, so patience with penetrating oil is worth the time.

Do I need to replace the gaskets every time I remove the exhaust?

Yes. Gaskets compress and lose their seal once they're heated and cooled. Reusing them causes exhaust leaks and poor performance. Most aftermarket exhaust kits include new gaskets, but buy spares in case one tears during removal — they cost $10 to $20 and save you a trip back to the shop.

Will a new exhaust trigger a check-engine light?

Only if the new system removes or modifies the catalytic converter and your bike's ECU isn't reprogrammed. Stock-style exhausts and systems that retain the cat converter typically don't cause issues. Your exhaust kit instructions will specify whether reprogramming is needed.

How tight should I torque the exhaust bolts?

Check your exhaust kit's instructions — most specify 15 to 25 Newton-meters for header bolts and 8 to 12 for support brackets. Use a torque wrench to get it right the first time; over-tightening can strip aluminum threads on the engine, and under-tightening causes leaks. If your kit doesn't specify, use 20 Newton-meters as a safe middle ground for header bolts.