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Booster Plug opinions

Keep cruising at 8k rpm and you 'll be buying a new RT sooner than not...but hey! its the way of crouch-rocketeers' culture. If its good for your ego to rev that high, it could not be that bad for the bike--as the logic goes.

With a booster your cruising is around 3500-3800. The engine runs easy and strainless on a flat road. Particularly in 4th and 5th gear. Mine cruises the easiest at close to 38 on sixth gear doing around 74 mph (which is when I got a ticket).

Without the booster your engine runs dry to meet EPA standards. But then, without a booster you have more money to buy several beers and YOU are not dry. So it may be a personal choice of dryness preference.

If you care to note, feel the pegs under you; they are a good indicator. When there is the least amount of vibration on your feet, your engine rpm is at a balance point with the torque needed to go at that speed--not pulling and not dragging...check the tach then....if it is at 8K write me back, it might persuade me to change my driving habits.
 
And why would I need a new BMW if I run it up to the factory recommended red line? I don't need more power for cruising and see no harm in winding the engine out to its designed capacity. Cruising is another matter altogether and requires no power over what overcomes wind/rolling resistance. If you think added fuel is "good" for your engine you don't understand what happens when excess fuel washes the cylinders dry and adds contaminants to your crankcase. I try to run fifty degrees on the lean side of max EGT.
 
And why would I need a new BMW if I run it up to the factory recommended red line? *I don't need more power for cruising and see no harm in winding the engine out to its designed capacity. *Cruising is another matter altogether and requires no power over what overcomes wind/rolling resistance. *If you think added fuel is "good" for your engine you don't understand what happens when excess fuel washes the cylinders dry and adds contaminants to your crankcase. *I try to run fifty degrees on the lean side of max EGT.

Interesting about 50 degrees on the lean side. That's about the mixture that gives Best Economy. I've been pushing my R1150RT toward Best Power mixture, on the rich side. I'm curious how you get your bike to run 50 degrees on the lean side since the O2 sensors tries hard to produce a stoichimetric mixture of 14.7:1 or about peak EGT.
 
Just like in an aircraft: Thermocouple in the head pipe, transistorized loop from the exhaust sensors back to the central fuel computer that allows one to cheat on the voltage seen from the sensora
 
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stoichimetric

Ok, I am lurking but I must also ask how to run lean of stoichimetric mixture on one of these bikes. I am totally in favor of lean of peak operations with the proper instrumentation to monitor both CHT and EGT but how can this be done with these bike systems? I have flown a couple of aircraft with the fancy instrumentation and I played with lean of peak and it worked wonderfully. Although my instincts from many years of flying are to stick to rich of peak. As an aircraft mechanic though, the sensors for those fancy instruments are a pain in the butt to work with. I also think it is totally to each their own with regard to making these modifications which may or may not make significant improvements.
 
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Just like in an aircraft: Thermocouple in the head pipe, transistorized loop from the exhaust sensors back to the central fuel computer that allows one to cheat on the voltage seen from the sensora

Since I've got time in an A36 Bonanza, and am used to having my hand on the mixture control, I've got some questions. First I want to mention that I've richened my R1150RT by adding an Innovate Motorsports LC-1 Wideband O2 sensor with Narrowband output. I could also reprogram Lambda to run lean.

So I understand the idea of an EGT sensor and circuit, what ECU signal do you modify? Also, have you disabled Closed Loop operation?

Ok, I am lurking but I must also ask how to run lean of stoichimetric mixture on one of these bikes. I am totally in favor of lean of peak operations with the proper instrumentation to monitor both CHT and EGT but how can this be done with these bike systems? I have flown a couple of aircraft with the fancy instrumentation and I played with lean of peak and it worked wonderfully. Although my instincts from many years of flying are to stick to rich of peak. As an aircraft mechanic though, the sensors for those fancy instruments are a pain in the butt to work with. I also think it is totally to each their own with regard to making these modifications which may or may not make significant improvements.

Did my own annual inspections and am inclined to agree with you. To be kind to the engine and to get top speed, I almost always ran 100F rich of peak. That's at an AFR in the range of mid 13:1. I've been testing AFRs between 13.8 and 14.2. It makes a significant difference to torque, smoothness and driveablility, just as in the plane. It feels like a new, different more powerful motorcycle. The LC-1 is a straightforward install, keeping the Motronic operating as designed but adding a programmable AFR switching point.
 
Booster plug

I posted in December with gaines from a combination of cam sprockets, exhaust and FRK module. I have since taken my R1200ST back to Dave Campbells shop and rechecked the AF ratio and decided to tune with a PC 3. We ended up with more HP thru the midrange than with FRK but the real gains were in torque. The motor picked up 6 ft at 3500 and 19 ft at 5500. Those figures are compared to a stock motor with a free flow exhaust. The HP and TQ modified and stock cross at about 7500 rpm. As you can tell this makes a great motor especially two up and loaded. Most of these gains can be attributed to the cam sprockets and the PC3. For the RT,GS riders looking for more low end and mid range power this could be something you would be interested in.
 
I posted in December with gaines from a combination of cam sprockets, exhaust and FRK module. I have since taken my R1200ST back to Dave Campbells shop and rechecked the AF ratio and decided to tune with a PC 3. We ended up with more HP thru the midrange than with FRK but the real gains were in torque. The motor picked up 6 ft at 3500 and 19 ft at 5500. Those figures are compared to a stock motor with a free flow exhaust. The HP and TQ modified and stock cross at about 7500 rpm. As you can tell this makes a great motor especially two up and loaded. Most of these gains can be attributed to the cam sprockets and the PC3. For the RT,GS riders looking for more low end and mid range power this could be something you would be interested in.

What were the actual peak numbers?
 
The peak number was a loss of 2 HP at 8000rpm compared to stock with aftermarket exhaust. I don't remember what the torque comparison at 8000 was. I will look it up if your interested.
 
The peak number was a loss of 2 HP at 8000rpm compared to stock with aftermarket exhaust. I don't remember what the torque comparison at 8000 was. I will look it up if your interested.

Most dyne numbers I have read are usually 100HP and 80ft/lbs of torque at the the rear wheel. I might guess from this that the BMW claimed numbers are a little conservative. 10% loss is a little low.
 
Bmw published figures are at the crank. On top of that every dyno reads different so that is why accurate comparisons are usually done on the same dyne. My peak HP figure was 98 Hp compared to 100 from a identical ST1200 to mine stock with a exhaust system. I was extremely happy with the results achieved with the PC3 because of the hugh gains in the midrange and a loss of only 2HP at 8000 rpm where I rarely if ever see. I knew going in that there was going to be a loss at peak rpm but thought it would be more based on what others using the sprockets have said, however, after seeing the AF ratios with the FRK module we thought the HP and Torque lost could be gained back. We not only gained some back but increase more in the low end and midrange with just a slight loss at 8000rpm where you rarely see anyway.
 
The HP and torque my bike has is enough for my riding style. But I think the engine is not smooth unless the ambient temp is around 40-45 deg F. So, I'm considering the booster plug.
But, I want to know if the richer mixture can damage the engine because it's too rich. I doubt it because from the factory it's mapped very lean and the increase in fuel brings it to what it should be.
 
But I think the engine is not smooth unless the ambient temp is around 40-45 deg F.

Devices that map the air input temperature do little to nothing when the bike is in closed loop mode. Once the engine is in closed loop mode meaning it is at operating temperature with a good signal from the O2 sensors and a more or less constant throttle the air temperature input is either unused or has negligible impact.

If you are looking for a smoother ride when tooling down the freeway (or other roads) at a steady state the Booster Plug or the Accelerator are not the device you want.
 
It's already smooth at constant throttle. I want the engine to run better at varying throttle like when you start off from a stop.
 
I run an IICE Air, which is similar to a BP. It smooths things out a bit at part-throttle, but really makes the bike punchier when you're beating on it. I like it, and for $75 it was a bargain.
 
Installed on my 2008 R1200GS

I have found a much steadier idle and a much smoother & more consistent low end rolling on the throttle. It was an epiphany for me.....
 
Installed booster plug on G650GS Sertao last month. GREAT help on starts and manuvering at low rpm. There's a photo of the install in my albums.
 
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