They had to change it to match euro 4 immision laws I think so prob altered fuelling and mapping I would imagine
Yep.. what Wayne said....all '17+ models are Euro-4 emissions compliant...the fuel/ignition map is a little bit different...but they're essentially the same as the earlier models performance wise. The ODB-II port under the seat is different too to comply with Euro-4 requirements....the '15 & '16 models have the round connector, the later bikes have the normal OBD-II port.
There was some talk going around that the 19+ models may even be Euro-5 compliant but I can't find any evidence of it on the interweb.
Smithy.