BC calculates the average since the last RESET.
If you do not regularly reset, (for instance over a 500 km long period) the indication will average out to a certain value, whereby it does not alter irrespective whether you drive fast or slow the last km's
It is apperantly NOT an actual fuel consumption indication.
Sounds like this is causing confusion, and seems VERY usefull fuction for BMW to add in the BC menu:
- 1 function for average fuel consumption (resettable)
- 1 function for actual fuel consumption
(Even the FJR1300 of 2006 has both possibilities)
Jan