Ok. What I had in the esc(2.1) when the motor smoked was,

Drag brake. 0
DRRS. 9
Brake force. 75%
Rev. force. 75%
Initial brake. 0%
Neutral range. 6%
Boost timing. 40 deg
Turbo slope. 18 deg
Overheat protection. on
Turbo timing. 36 deg
Boost start rpm. 2000
Turbo delay. 0.2
Timing acc. 350.

With this setup I was running 6.8 fdr and the motor was mostly coming off at 60-80 degrees Celsius depending on ambient temp. I used to run the standard comp v3 motors but they always got hot quick too so when the 1 cell motors were released the change was very easy. I have run this motor for around 3 months with no problem on a bigger track running the same esc settings and fdr so am at a bit of a loss as to why it didn't like the last track.