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Changing exhaust question

E

eric r

New member
O.K., some say that removing the cat and adding an aftermarket muffler will further lean the engine and possibly "hole a piston". Doesn't the Motronic adjust mixture according to the O-2 sensor? Is it really possible to damage the engine by making it breathe and exhale more efficiently?
Is the Techlusion really necessary?
I'm just looking to take off a little weight and get rid of some of the Catalytic heat!
If I keep stock intake, cermaic coat the header, and de-constrict the exhaust, I'll just be easing the outflow ...so what could it hurt?
2000 1100-R w/ 32k miles
 
if its just a cat elim you're doing, you should be fine with no fuel work. if the bike surges and you can't tune it out, then some fuel adjustment would be warranted.
 
I modified my stock muffler by making my own internals, but kept the cat. It leaned out enough to really pop on decel more than before. I installed a Techlusion and the popping in minimal and I still average 42 mpg and almost 50 mpg on good days.
 
a fuel map chip (really what we're talking about here) sets parameters that it will work within, a max and min threshold, if you will. you can exceed those limits through changes in intake and/or exhaust. O2 sensor will not change those max/min limits, so if your exhaust work pushes the overall oeprating conditions too far to the lean side of things, nothing you have installed stock can adjust for that, and things could get dicey. i went with a Laser cat elim and mufflers. the bike runs much stronger with the matching laser chip. and once you go with the cost of the exhaust mods, a matched chip is not all that much more. bike does run stronger with the full set done. you said you wanted to "deconstrict" the exhaust. if that menas mufflers and cat elim, i'd drop on a chip or techlusion as well
your bike, your choice.
 
Chips ?

All I am seeing available is the Techlusion. Two models, one deletes the O-2 sensor, and one does not. What I need to know is which way to go on a stock motor with cat eliminated and a straight through design muffler.
 
which exhaust system (cat elim and/or cans) are you considering? most have thier own proprietary chip, or can make the recommendation for you. the advantage of the Techlusion, as i understand it, is that you can fine tune it to your bike's exact operating conditions.
 
Going with Two Brothers...I think

Probably the 2-brothers. I have also considered having a mid-pipe bent and putting on a SuperTrapp.
In any case, I am sending the header in to JetHot and having it ceramic coated. That alone WILL lean out the engine. I have experience with JetHot on race cars (small block Chevy motors), and rejetting was always necesary. On airplane exhaust, a notable power increase was observed (mixture is manual on those).
The 2-brothers low mount system along with an RT left saddlebag seems to be inevitable.
 
Just be aware that TBRs are one of the louder mufflers out there, and require repacking, or they just get louder. Laser, Staintune and Remus are all superior alternatives, imo, and all offer "tuned" pipe/mufler/ chip options.
 
eric r said:
All I am seeing available is the Techlusion. Two models, one deletes the O-2 sensor, and one does not. What I need to know is which way to go on a stock motor with cat eliminated and a straight through design muffler.
Click to expand...

For what you want the 1031 without the O2 sensor is excellent and is the best value. I'll send you a private message with a link (I sell them :) ). I've used this unit with several R1100 bikes and it works very well. Two Brothers exhausts are very loud and need constant repacking. You can get just the crossover pipe from Two Brothers and mate your own can to it. I've tried the Supertrapp like this and it is loud if you add enough discs to get good performance. Hope this helps,
Mike
 
TBR Cat Eliminator

I recently installed a TBR Cat Elim on my R11RTP. I was looking to reduce the weight and to give it a bit more tone. Had to install a P-1X Power Tip to get it down to a more tolerable level. I am getting the mentioned excessive popping on deceleration even tho TBR says no messing with the FI required. I previously removed CAT plug to cure the surge issue. (Thanks Jim Moore.) When I get the spring service done in March, I will have the fuel system completely remapped.
 
JimRogersRTP said:
I recently installed a TBR Cat Elim on my R11RTP. I was looking to reduce the weight and to give it a bit more tone. Had to install a P-1X Power Tip to get it down to a more tolerable level. I am getting the mentioned excessive popping on deceleration even tho TBR says no messing with the FI required. I previously removed CAT plug to cure the surge issue. (Thanks Jim Moore.) When I get the spring service done in March, I will have the fuel system completely remapped.
Click to expand...

unless 'm mistaken (and i really do not think i am) to "remap" your R11 requires a new chip in the Motronic, or something like the Techlusion unit. BMW does not offer a performance chip, so you 're looking at the aftermarket there as well.
 
Most likely. Not really sure what the mech plans on doing as we did not get into the details since we are talking March to have the work done. The conversation started when I tried to buy his decked out 10 GSA that he just replaced with a MultiStrada. Since we could not come to a mutually agreeable price, we started talking about what I could do to 'Hilda'. About the only things left are the fuel delivery system work and tuning the Ohlins to my weight. Looking forward to Spring. I will post a detailed report on what he does and the results, similar to the one I posted on my trials and tribulations in going wireless (BlueTooth) on the sound/communications system I now run.
 
jduke said:
The cheapest upgrade is a K bike fuel pressure regulator.
Click to expand...

and from everything i hear about it, its value is also "the cheapest".

before you go looking into hobnailing together some "parts bin A" and "parts bin B" exhaust system, maybe you should consider some of the full system options? There's no huge performance increase either way, but likely smoother running & lighter weight with a much more satisfying sound.
 
I disagree Bikerfish. I noticed an improvement in the idle and throttle response immediately. If someone is concerned about the lean condition of the engine that comes from the factory, this is a cheap fix.
 
94 r1100rs

I added a Staintune exhaust system with their cat system to my '94 R1100RS. Never could get the bike to sound and run right. I was planning on going back to the stock system. As a last try, I got the Techlusion TFI control box. Hooked it up via their instructions and the bike runs and sounds great. I've gotten a few comments from BMW riders about how well the bike sounds. Money well spent.
 
Loud exhaust

OK, I am hearing that two brothers are loud ... I'm not looking for aftermarket Harley Loud, just a litlle noise so I can tell it's running! For example: I took the stock exhaust off my Honda ST1300 and put on delkovics with the baffle removed. Not loud, just throaty and nice. I just sold a Kawasaki Vulcan 900 that I put COBRA 2 into 1's on...Now that was L O U D !
My buddy has a GS with Remus cat eliminator and can ...Sounds like a big-ass dirt bike, and not too loud.
$1000 plus for an exhaust system? Now that's TOO LOUD! No way these things should cost that much.
I have a used two brothers system sitting in the garage for the ST1300, and now I'm contemplating putting it on and see just how loud it is in comparison to the Delkovics //// One man's loud is another man's not so bad loud...
What if I just mildly debaffle the stock muffler and let the cat do the muffling? Anybody done that?
 
your best overall results will come from going with a cat eliminator, as it typically drops ~13 lbs, removes a heat source for the trans, plus adds a touch of throat to the bike. if that is not enough change in sound for you, then consider some muffler action.

jduke- have never used/ridden a bike set up with a K-fpr, so only stated it as "from everything i've heard." your feedback makes it "1" in the "for" camp.
 
I've put almost 200,000 miles on oilheads so I've tried about everything out there to get more power out of them at least once....
Only went back to stock on things that weren't noticeable or went backwards. The K bike fuel pressure regulator was a keeper.
Opening the intake and exhaust always helps a stock bike, worth the price is another question.
One of the most impressive changes was going with Lennies Sprockets. Really gave the bike a kick at 4500 rpm.
 
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