Yamaha R15 version 2.0’s divided sport seats and the R15-S’s single seat have a lot of difference for the pillion. The bikes are based on the same architecture and uses the same components all over their bodies. They may be interchangeable and you can ask the company officials about the same at your nearest Yamaha service center. The motorcycle would become a bless for the pillion if it can be swapped with the older version’s rear end.