Actual difference is the ECU box, they are new for each model ie Jnr / Snr / DD2. Mostly it provides a higher rev limit.
There is also a new wiring loom and battery box top and switch, and the ECU is mounted alongside the battery in the later version.
If you want to upgrade from 2015 to 2017 'spec' then just buy the later ECU, the rest is not going to make any difference to the performance , reliability or anything else.
Comments1
Actual difference is the ECU box, they are new for each model ie Jnr / Snr / DD2. Mostly it provides a higher rev limit.
There is also a new wiring loom and battery box top and switch, and the ECU is mounted alongside the battery in the later version.
If you want to upgrade from 2015 to 2017 'spec' then just buy the later ECU, the rest is not going to make any difference to the performance , reliability or anything else.