Jeremy McCreary
Bought it anyway
- Region
- USA
- City
- Carlsbad, CA
Spec's SL 2 documentation says that the mechanical Pm and power ratio readings on the TCU and app are just estimates obtained by multiplying measured electrical Pm by a constant assumed efficiency of 80%. Don't recall that they show raw electrical Pm data anywhere.the Pm data has been adjusted with the efficiency curve above to be Pm mechanical.
Just confirming that you backed out the assumed 80% before applying your empirical efficiency vs. cadence curve. If not, the gap between your empirical Pm/Pr ramp slope data and the corresponding Spec MicroTune data is even wider than seen in @mschwett's last plot.
Another reverse-engineering hurdle: The new empirical 40/40 and 40/100 Pm vs. Pr plots once again show that ramp slope S = Pm / Pr varies strongly with both E and M in assist mode E/M.
This is certainly unexpected from Spec's 2024 documentation. The clear message then was that S depends only on E. Nary a hint that S might also vary with M.
So we'll have to map out this mysterious S(E,M) function empirically. Is it the same for all E/M modes, MicroTune and otherwise?
Unfortunately, much more field work ahead.
Last edited:
