Rocking up the Rockster - Remus, tuning etc

[riceburner]

Where is the Cat Code Plug? I'd like to try it without. I am running a Staintune mid (Y pipe) and an Akrapovic can, no db killer. The sound is perfect.. not to loud.

JB

It's in the fusebox

[Andrew s]

Just bought a Remus end can and Y piece, looking forward to fitting them. Don't think I'll do anything else regarding engine or fuelling.

[ROXTR]

You say that now....

Once you start adding farkles it's hard to stop.

[Andrew s]

I know what you mean, Lennies Roccket Sprockets might be tempting, but being realistic you can't expect much from this engine, best to just enjoy what you got.

[Roger 04 rt]

Some comments below:

If you remove CCP then AFAIK there is no closed loop adjustment but the map should be richer to begin with. I am currently running a jumper that simulates CCP for "regular" with CAT. I might play with it later to see if it makes any difference

On the R1150, when you remove the Coding Plug (CCP), the engine runs one of the Closed Loop maps for R1150R/GS. I believe from looking at the map it has a bit more timing advance. No real performance difference, not a richer mixture.

As I understand it, the closed loop is the way the Motronic works, with a built in default map - the CCP basically just applies a different fueling map - kinda like applying a different 'theme' to a Windows desktop - same data, just handled slightly differently. That way BMW could have a very restricted map for California/USA, and then slightly different mapping for different markets (eg Australia would probably be mapped differently to Europe).

That's about right. It selects a "theme" for the specific intake tubes, cams and heads. There are two for the 1150R/GS: No plug and Yellow Plug. The Yellow plug may be more tolerant of lower octane. Both maps start out lean. Neither is a "default" rich map.

Suggested reading regarding R1150** Motronic tuning:
http://www.advrider.com/forums/showthread.php?t=749080

We haven't had anyone dig so deep here on Roadster board, specific to fuel injection, but the info is directly applicable.

The above info in the thread is 100% applicable to the R1150R/Rockster, as far as I can tell.

Closed loop operation is when one part of the output is fed back to the input of the system to accomplish control. Hence closed loop. In this Motronic implementation the only feedback to the system is the O2 sensor (or lambda sensor for you Europeans). With the CCP you can select different maps, however some of those maps are "open loop" where the system is no longer looking to the O2 sensor to provide feedback, it is always running in open loop. This would be the map for "no catalyst, no O2 sensor". If we assume that without catalyst which could have been the default for some markets (need confirmation), the engine is breathing a little better, ie more air out, more air in, we could assume that this default map would be richer for this reason. It is also a common practice to design open loop maps to run a little on the rich side since the power is about the same and the "safe window" is wider before lean burn damage can occur.
Open for comments.
So to the original question, main restriction is the CAT, therefore engine performance and mixture is not really affected by the muffler.
This is theory, in practice many people have been running various mufflers (or none) with no adverse effects on the engine.

Only the R1100R/GS/RT have Open Loop maps (No Coding Plug and 30-87a), which look for a CO Pot to trim Idle fueling. The R1150s were all shipped with cats and are Closed Loop.

The R1150 BMW maps don't have a richer default map. In fact if you run fuel with 10% ethanol, much of the map is leaner that 14.7:1.

Most changes to the exhaust are accommodated by the Motronic. No muffler or Cat may lead to some fresh-air reversion fooling the O2 sensor.