Steve is right. Euro emissions regulations for motorcycles are not be applied retrospectively.

Currently bikes have to comply with Euro 3 for type approval in the EU, but are not tested at the MOT. Only a new bike at point the point it leaves the factory. When Euro 4 is rolled out from 1st January 2017 for all new bikes requiring type approval, emissions will be tested for the MOT, but only from 1st January 2018.

From 1st January 2018 all pre 2017 bikes will just require a "visual" emissions check as is currently the case. You haven't anything to worry about.

FYI, as the XT range stands, none of the current models will pass Euro 4. Which is why it's highly likely that that the XT660 will end production in the year or so...

__________________