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Adding high flow filters (more air) and removing the cat from the exhausts (exhaust gas exits more quickly) makes the engine run even leaner. This will cause the engine to produce less power, worse throttle response, possible detonation/ping, burnt exhaust valves. From factory, the engine's AFR's are at the absolute limit of the safe area, so adding intake/exhaust mods typically exceeds these.
Thanks, that tends to confirm my views of sticking with stock. I've always been a little dubious at posts from people saying they've removed the cat, added a KN filter, and that the bike is smoother / a little more powerful. I'll keep an open mind until the day I try it myself (if that ever happens), but unless one retunes the engine (or retunes itself!), I've always found it hard to believe how some guy in a shed could improve the engine performance from an engine that took many engineers to tune. The only doubt comes exactly from that - pollution limitations (and ECU ajustments). In theory, I guess the engine could run better without the cat and with more air, but indeed it makes sense that it would need more adaptations. I guess this is where the electronic gear comes in, that or the actual reprogramming.
 

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Thanks, that tends to confirm my views of sticking with stock. I've always been a little dubious at posts from people saying they've removed the cat, added a KN filter, and that the bike is smoother / a little more powerful. I'll keep an open mind until the day I try it myself (if that ever happens), but unless one retunes the engine (or retunes itself!), I've always found it hard to believe how some guy in a shed could improve the engine performance from an engine that took many engineers to tune. The only doubt comes exactly from that - pollution limitations (and ECU ajustments). In theory, I guess the engine could run better without the cat and with more air, but indeed it makes sense that it would need more adaptations. I guess this is where the electronic gear comes in, that or the actual reprogramming.
Don't need to tune. You can run the AF-Xied which alters the O2 sensor signals. Simple plug n play device. I'd even put these on a unmodded modern bike I owned if I wasn't doing a flash tune. It will run far smoother. The AF-Xied is proven to work long term, but is takes around 1000km before it starts to work as the ECU needs time to fully make adaptions.
 

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Why would you want additional RPM?. Has nothing to do with AFR's. Running richer mix doen't increase RPM. The idle RPM is an ECU controlled target.
I may have a reasonable number of motorcycle miles under my belt but am pretty much a novice when it comes to dirt/off road riding. I found my '05 GS a bit hard to handle at the lower speeds I'm comfortable with in the dirt unless I used lots of clutch on/off trying not to slip the clutch on my hexhead. Adding the accelerator module helped in that specific area. 2500 RPM in 2nd gear was usable with the module. It was not usable without the module.

That is all I was looking for. I didn't care about IDLE RPM (which was not affected) or AFR changes. I simply wanted to ride the bike at about 2500 RPM in 2nd gear when on dirt roads. And maybe when splitting lanes.

My '13 does just fine at the dirt speeds I like so there was no need to make any changes.

Does that answer your question?
 

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BP is a hit for me. After 20,000 alms across India and SE Asia with the standard tune it was a handful at times. Slow speed first gear fully loaded through mountain passes was a challenge with the motor often stalling and spitting. They run far too lean as standard. Mines a 2013 LC model. On return to OZ I fitted the BP and it cured the problem 90%. The final 10% of cure came from upload of the latest ECU software by my local shop Morgan and Wacker. Must be some big improvements in the latest ECU software. Its a different bike now. Just for the record I had 2 other mods done under warranty while the bike was in the shop
1. New exhaust cams to cure decompressor tick at idle.
2. Sleeves pressed on to front fork stanchions to improve strength at top triple clamp. Bloody hell ... I've just thumped my way over some of the worst roads in the world and am so lucky nothing collapsed.
Thanks BMW for your warranty support ... but I'd have thought the forks should have been sorted years earlier.
 

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I have read through this thread and while there is a lot (mostly) of good factual data I have to agree with bmwbob51 in that the ECU is unable to fully kill the effects of a booster plug and that RAIDER will not experiance the bike reverting back to its former behavior.
Roger 04 has been preaching this for years on ADVRider for years, he comes across very knowledgeable on the subject but the fact is that almost everybody (myself included) that has experience with booster plugs of all different varieties has not had the symptoms they were trying to correct re-appear becasue the ECU learned it's way around the device.
The reason is simple; the ECU (BMS-K) isn't programmed to be able to tell what the real perimeter should read, it has to accept the data coming in from each sensor as gospel, in other words if the IAT sensor is telling the ECU that the outside air temp is 32F (regardless if reality) the ECU accepts that as fact and adjusts fueling accordingly, so long as the O2 sensors readings remain within range which they will with such a small input modification, the ECU just hums along, the ECU does not attempt to precisely adjust fueling to the nth degree.
I used the simplest of all mods by putting a resistor inline with the IAT sensor to fake a lower intake air temperature on my 05 and that worked (smoothed out low speed ride-ability) for the extent.
 

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I have read through this thread and while there is a lot (mostly) of good factual data I have to agree with bmwbob51 in that the ECU is unable to fully kill the effects of a booster plug and that RAIDER will not experiance the bike reverting back to its former behavior.
Roger 04 has been preaching this for years on ADVRider for years, he comes across very knowledgeable on the subject but the fact is that almost everybody (myself included) that has experience with booster plugs of all different varieties has not had the symptoms they were trying to correct re-appear becasue the ECU learned it's way around the device.
The reason is simple; the ECU (BMS-K) isn't programmed to be able to tell what the real perimeter should read, it has to accept the data coming in from each sensor as gospel, in other words if the IAT sensor is telling the ECU that the outside air temp is 32F (regardless if reality) the ECU accepts that as fact and adjusts fueling accordingly, so long as the O2 sensors readings remain within range which they will with such a small input modification, the ECU just hums along, the ECU does not attempt to precisely adjust fueling to the nth degree.
I used the simplest of all mods by putting a resistor inline with the IAT sensor to fake a lower intake air temperature on my 05 and that worked (smoothed out low speed ride-ability) for the extent.
So does the booster plug work? or not?
For a 2018 R1200GSA
 
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