Exhaust dilemma...R1200RT

mreimler · 10-23-2009, 05:48 PM

I recently hit a lawn mower grass catcher bag that was on the freeway and (among other things) it put a large dent (2'' wide and 1/2+'' deep) in the crossover tube on the header of my '09 R1200RT. The insurance guy was here yesterday and dropped off a nice check so here’s the question:

What do I about the header? Ride it with the dent and not worry about it? Buy another stock header? Buy a header or full exhaust from somebody else? I don't want louder. More power is great as long as fuel mileage doesn't go into the crapper.

What are the pros and cons of getting rid of the CAT?

I replaced the CAT on my '02 1150ADV with a "Y" pipe, muffler and a Power Commander and after multiple dyno tunes, it never ran down low as well as the stocker and fuel mileage went way down. That experiance makes me concerened about trying to make the bike run "better"

Anyone have experience and/or advice about the RT?

Semper_Fi · 10-23-2009, 06:53 PM

You can look at Akrapovic and Remus- they make various exhausts for BMW bikes.

The other choice is replace with stock

RTRyder · 10-23-2009, 08:59 PM

Ztechnik also makes a full stainless steel system to fit the RT, I have one on mine. Somewhat less expensive than the big name makers, I'm happy with the Ztechnik overall, just be aware that many tubular engine guards won't work with their header pipes due to the placement of the O2 sensor on the right side pipe. If that's not an issue for you, then you'll likely be happy with the system.

Noise level is a bit higher than stock, but not enough to be of any concern, I think it gives the RT just the right exhaust note, but it's certainly not the stealthy whisper of the stock system. They claim slight gains in torque and HP, the big selling point being it weighs significantly less than the stock system. Seat of the pants feel is the torque band is improved over the stock setup, especially between 2000 - 3000 rpm, I can go a gear higher in that range without lugging the engine and it pulls smoothly without downshifting as long as you're not in a big hurry. I track fuel mileage in a spreadsheet and have found zero difference in MPG vs. the stock system.

If you're looking for big gains in torque and HP, this isn't the system you want. If you want to lose the Cat and a bit of weight with a slightly beefier exhaust note, then this one will fit the bill.

10-31-2009, 12:56 AM

Quote:

Originally Posted by RTRyder

Noise level is a bit higher than stock, but not enough to be of any concern, I think it gives the RT just the right exhaust note, but it's certainly not the stealthy whisper of the stock system. They claim slight gains in torque and HP, the big selling point being it weighs significantly less than the stock system. Seat of the pants feel is the torque band is improved over the stock setup, especially between 2000 - 3000 rpm, I can go a gear higher in that range without lugging the engine and it pulls smoothly without downshifting as long as you're not in a big hurry. I track fuel mileage in a spreadsheet and have found zero difference in MPG vs. the stock system.

If you're looking for big gains in torque and HP, this isn't the system you want. If you want to lose the Cat and a bit of weight with a slightly beefier exhaust note, then this one will fit the bill.

I, too, am thinking about adding an after market exhaust to my '07 RT and I not sure where to begin.

The above info on the Ztechnik system is very helpful.

Can anyone offer similar info on the Remus or other systems?

I am more concerned with gas mileage change and perform enhancement than noise.

If a person was looking for performance enhancement through an exhaust system which one should be considered and what are the draw backs?

Also, if you were going to install an after market exhaust system which system would you choose and why?

Thanks for your help.

Vaughnb · 11-02-2009, 10:26 PM

In 20 years of fixing bikes, planes, boats and anything that burns fuel, I have picked up a few things.

If you want the perfect set up, leave it alone. If you want it to be reliable, keep it stock.

RTRyder · 11-03-2009, 12:50 PM

Quote:

Originally Posted by Vaughnb

If you want the perfect set up, leave it alone. If you want it to be reliable, keep it stock.

With 35 plus years of wrench turning under my belt, I'd have to strongly disagree with the first part of that statement. Manufacturers today are faced with the competing requirements of good fuel mileage, maximum horsepower output, and minimum noise and exhaust emissions. Any stock system you're likely to find on the average car or motorcycle is going to be a compromise between all of those competing factors to find a balance that gives decent MPG and performance without exceeding allowable emission and noise thresholds, hardly the perfect setup.

That said, the majority of the aftermarket systems will generally sacrifice low noise and/or emissions, and potentially fuel mileage in an attempt to increase horsepower. Simply opening up the flow of exhaust gasses from the combustion process can increase power to some degree, but it doesn't mean it's a good system, I call this the shotgun approach to engineering. A well balanced and well engineered system can produce moderate gains in torque and horsepower without completely tossing fuel mileage and noise levels into the trash bin, and if it retains an existing catalytic convertor may not change emission levels at all. Whether or not said system will meet the same stringent guidelines the OEM manufacturer has to meet is a subject that is currently gaining a lot of attention with all of the involved parties and has led to the creation of a standardized testing methodology for sound levels by the SAE organization, a first step to addressing some of those issues.

Bottom line here is that a well designed and thoroughly tested aftermarket exhaust can produce a better running, slightly more powerful machine without sacrificing reliability and fuel mileage or increasing noise and emissions levels beyond acceptable limits. If you are expecting BIG gains in power and performance, you won't get it simply by modifying the exhaust system. It takes a full systems engineering approach to tune the relevant bits and pieces to make that happen, there's only so much you can do by increasing exhaust flow without also adjusting fuel flow, cam timing, compression, etc., etc., and down that path lies decreased reliability and usability.

Maylett · 11-03-2009, 02:21 PM

Good points RTRyder, and you're right.

Still, not everyone here is a veteran mechanic or a graduate from an automotive engineering school. Many of us know just enough to be dangerous. Those factory-engineered compromise and balances can easily go awry as one starts tinkering with enhancements and replacements that have quality problems, unintended consequences or simply don't live up to expectations.

Just my opinion, but when it doubt, stock is the safest choice. Then again, safest isn't always the most fun.

10-23-2009, 05:48 PM	#1
mreimler Registered User Join Date: Aug 2009 Location: Shakopee, MN Posts: 9	Exhaust dilemma...R1200RT I recently hit a lawn mower grass catcher bag that was on the freeway and (among other things) it put a large dent (2'' wide and 1/2+'' deep) in the crossover tube on the header of my '09 R1200RT. The insurance guy was here yesterday and dropped off a nice check so here’s the question: What do I about the header? Ride it with the dent and not worry about it? Buy another stock header? Buy a header or full exhaust from somebody else? I don't want louder. More power is great as long as fuel mileage doesn't go into the crapper. What are the pros and cons of getting rid of the CAT? I replaced the CAT on my '02 1150ADV with a "Y" pipe, muffler and a Power Commander and after multiple dyno tunes, it never ran down low as well as the stocker and fuel mileage went way down. That experiance makes me concerened about trying to make the bike run "better" Anyone have experience and/or advice about the RT?

10-23-2009, 06:53 PM	#2
Semper_Fi Runs with Scissors Join Date: Aug 2008 Location: Gloucester MA Posts: 1,974	You can look at Akrapovic and Remus- they make various exhausts for BMW bikes. The other choice is replace with stock __________________ 2009 KGT1300 Red Apple Metallic (mine), 2005 R1200ST Piedmont Red/Light Magnesium (hers) Luis Roth BMWMOA #143775 BMWMOA Moderator

10-23-2009, 08:59 PM	#3
RTRyder Registered User Join Date: Oct 2007 Location: 42.09°N 71.05°W (eastern MA) Posts: 90	Ztechnik also makes a full stainless steel system to fit the RT, I have one on mine. Somewhat less expensive than the big name makers, I'm happy with the Ztechnik overall, just be aware that many tubular engine guards won't work with their header pipes due to the placement of the O2 sensor on the right side pipe. If that's not an issue for you, then you'll likely be happy with the system. Noise level is a bit higher than stock, but not enough to be of any concern, I think it gives the RT just the right exhaust note, but it's certainly not the stealthy whisper of the stock system. They claim slight gains in torque and HP, the big selling point being it weighs significantly less than the stock system. Seat of the pants feel is the torque band is improved over the stock setup, especially between 2000 - 3000 rpm, I can go a gear higher in that range without lugging the engine and it pulls smoothly without downshifting as long as you're not in a big hurry. I track fuel mileage in a spreadsheet and have found zero difference in MPG vs. the stock system. If you're looking for big gains in torque and HP, this isn't the system you want. If you want to lose the Cat and a bit of weight with a slightly beefier exhaust note, then this one will fit the bill. __________________ Ken D 2007 R1200 RT 2001 Kawi Concours 1975 Norton 850, 1971 Norton 750, 1957 Norton ES2

11-02-2009, 10:26 PM	#5
Vaughnb Registered User Join Date: Oct 2009 Posts: 9	Stay stock if you can. In 20 years of fixing bikes, planes, boats and anything that burns fuel, I have picked up a few things. If you want the perfect set up, leave it alone. If you want it to be reliable, keep it stock.

11-03-2009, 02:21 PM	#7
Maylett Registered User Join Date: Jun 2009 Location: Utah Posts: 63	Good points RTRyder, and you're right. Still, not everyone here is a veteran mechanic or a graduate from an automotive engineering school. Many of us know just enough to be dangerous. Those factory-engineered compromise and balances can easily go awry as one starts tinkering with enhancements and replacements that have quality problems, unintended consequences or simply don't live up to expectations. Just my opinion, but when it doubt, stock is the safest choice. Then again, safest isn't always the most fun.