I am going to make two assumptions here:
1) Your original motor was silver and not black ?
2) Your engine suffered a mechanical failure ?
I had a 2014 GSA that BMW very kindly fitted a 2017 engine to due to a minor corrosion issue. When I decided to part exchange the GSA for a GS I explained to the selling BMW dealer that the servicing BMW dealer had replaced the motor due to corrosion. The salesman at the selling BMW dealer got quite funny about it. In fact, I came very close to telling him to FRO when he then tried to chip me on the offered part exchange price. He claimed that he wouldn't be able to sell my GSA for the same price as a 'normal' GSA that hadn't received a new replacement motor
Even dealers can get funny when it comes to non original stuff despite the fact that a 2017 motor is a massive improvement over a 2015
I would just price it as a high mileage 2015 bike and see what gives
On the subject of deals. My local dealer NOG are doing pre registered R1250GS Exclusive models at £15650 and the 1250 Rallye at £15950 throughout the month of June
1) Your original motor was silver and not black ?
2) Your engine suffered a mechanical failure ?
I had a 2014 GSA that BMW very kindly fitted a 2017 engine to due to a minor corrosion issue. When I decided to part exchange the GSA for a GS I explained to the selling BMW dealer that the servicing BMW dealer had replaced the motor due to corrosion. The salesman at the selling BMW dealer got quite funny about it. In fact, I came very close to telling him to FRO when he then tried to chip me on the offered part exchange price. He claimed that he wouldn't be able to sell my GSA for the same price as a 'normal' GSA that hadn't received a new replacement motor
Even dealers can get funny when it comes to non original stuff despite the fact that a 2017 motor is a massive improvement over a 2015
I would just price it as a high mileage 2015 bike and see what gives
On the subject of deals. My local dealer NOG are doing pre registered R1250GS Exclusive models at £15650 and the 1250 Rallye at £15950 throughout the month of June