This has been an area of dispute regarding the booster plug......it worked for people on the air cooled ones but not on the liquid cooled ones. There is a thread buried here and one on advrider which explains in detail the Booster Plug and why it doesnt work on the newer R1200GS/1250Strictly speaking the ecu (bike's brain) will compensate for the more free flowing exhaust. There is an area of the mapping called open loop where no compensation tales place, this is mostly at higher throttle opening positions. So if you were continually thrashing the bike then there could be a slim chance the bike will be running lean.
There is a product called booster plug BoosterPlug BMW R1250GS
which will add approx 6% extra fuel in the open loop area and may well be worth fitting (it works well on the r1200). Of course there is no way of knowing for sure without putting the bike on a dyno.
I would be loathe to go down the Power commander route, the best way is to hack into the ecu and adjust the fueling, which I have done on various Triumphs and Guzzis over the years but I am not sure if it is possible on modern Beemers.
On a R1200GS a full exhaust sytem will give an extra 3-4 bhp adding a Power commander may give double that.
Columbus I had it and removed it since I could feel absolutely nothing in the few months it was on the bike.Had a booster plug on an rt1200 wethead and it worked as advertised for twenty thousand miles. Sold the bike. There was no relearning by the ecu and going back to before it was installed. Think about how that could possibly happen anyway. It's telling the bike the air temp is lower. Does the ecu figure out it's installed and start to ignore it? People saying it does haven't had the plug. Just repeating what they have heard. I will get one for the 1250 as well. The 1200 wouldn't roll smooth at low rpms. Jerked for lack of a better term. Booster plug completely eliminated it. I could roll off a stop with just the clutch and no throttle. Level ground of course but before the plug there was no chance without it stalling. Now the 1250 is a lot better in the low end but could still use some more fueling so I will probably add one soon.
Well the 1250 is certainly a different animal. The bottom end is a ton better than the 1200 was. That's where the plug made all the difference. You are correct in it probably has no noticeable difference on this motor. I would add it only to get rid of the lean condition but that isn't even a priority as the bike runs so good as is. Mine does make oil disappear to some unknown place so it may help with that if I can get it running a little cooler with the plug.Columbus I had it and removed it since I could feel absolutely nothing in the few months it was on the bike.
Maybe mine was just busted.....didnt think of that.....
The theory behind the Booster plug is sound, it all depends if adding 6% extra fuel to certain parts of the rev range is the answer to your problems.
Before fitting one to my 1200 twin cam I did a lot of forum reading and it was difficult to find any negavity. My experience with ecu tuning does not stetch to BMW and certainly not a bike with various riding modes. On my previous bikes I could alter the air temperature/opressure table to give extra fuel much the same way the Booster plug does so I know it works in practice also.
It may or may not have an effect on the 1250 motor if needed at all.The only way for the layman to know is fit one and ride in a variety of temperature ranges over a extended period and decide if it was money well spent.
I am still waiting to access the benefits to my bike because I have only ridden in sub 10C temperatures so far. There is a seat of the pants gain in throttle response for sure. What would be beneficial is to have the module switchable for a proper assessment but for the money (I have the cheaper Accelerator module) it is worth a punt.
Exactly and thats what the ones who used it on the LC said that it makes no difference, me included.My bike is a 2010 R1200GS TU so air/oil cooled. The theory still applies to LC engines but the effects will be different assuming BMW mapped the ECU differently, which they surely would have.