Can any body please tell me with the evo brakes (integral abs) how is it the speedo works. Ie where is the speed sensed from front or rear and abs sensor. Any info would be appreciated
FIRST and foremost: the term "Evo brakes" has different meaning depending who is using it.
BMW has initially (around 2001) applied this term to the new ABS system having servos assisted modulator (using electrical motor to boost brake power hydraulically). These ABS modulator were also refered as "Intergral ABS system" made by FTE in Germany under contract for BMW. Variations of these have been used on K1200RS, K1200LT , K1200GT between 2001-2006 and also on most R1150 boxers models of the same era. Europe market got this new ABS design in 2001, BUT the USA market only got these as 2002 and later models.
Assuming your question was based on this type of ABS modulator the answer is:
Contrary to earlier models, the Integral-ABS system relies on a single rear wheel speed sensor for both function of Speedo AND also for ABS speed sensing. Earlier models (early k1200RS, K1200LT before 2001) had an additional speedo sensor bolted to the top of the rear-drive.
To work with a single rear wheel sensor for both functions, Integral-ABS modulator takes the signal of the rear brake sensor and converts the data to another format to be send to speedo. All this is done into an electronic board mounted on top of the modulator (where the large multi-pin connector enters).
There is no published data or specs about this speedo signal conversion, so in general when / If the ABS modulator is removed with its plumbing, you need to keep the top of the iABS modulator connected into the main harness so as to keep speedo signal (even if you loose the ABS capability). This part of the ABS modulator (the top circuit board) also manages the Front + Rear brake switches signal AND the rear night + brake light.
See this link for page 13 of a long thread about removing a similar modulator from a R1150 Boxer.
Page 13 will give you the main point above with pictures - if you care to read the whole thread be aware you are there for a very long time (220 post spread over 14 pages):
Simple, NO COST servo removal of 1150 IABS system - Page 13