I have an old 2004 BMW R1200GS. Recently I had a test ride on the latest model which was a lot peppier to ride and felt much better for it. Having established that I am too weak willed to go against my missus and spend the savings on a new bike I began wondering if I could stealthily improve my current bike. What I had in mind was a K&N filter, de-cat it and run a freer flowing end can. If I do this will the ecu on this model automatically adjust the fuelling (It has Lamda sensors) or will it run too lean? I.e. will I need to spend another couple of hundred quid on mapping.