HeyThe SL 1.2 is out in the wild with the '23 Levo SL.
From what we know so far, mountings and connections are all the same. It works with the existing battery and range extender (shorter 145mm instead of 160mm cable).
The motor is slightly larger due to the two piece aluminium honeycomb casing for noise reduction.
New 1.2 motor :
View attachment 113603
Previous (1.1) motor :
View attachment 113607
The torque sensor looks slightly different and you can see the casing on the drive side is thicker.
Hardware wise, from what we know so far, there were only slight changes made to the gears to make them slightly quieter.
There are claims that the new motor is slightly more efficient if used with the same settings as the 1.1 motor. This either means there were hardware changes that we're not aware of, or just with firmware they've managed to optimise the power delivery in a more efficient manner. Though they say they've re-tuned Trail 75% Support/80% Peak power and Turbo 100% support/80% peak modes, so this maybe where the extra "efficiency" comes from. Eco remains the same as previously at 35% support/35% peak power. If you want to use all the new power which is available, you'll need to up peak power to 100%.
Allan Cooke from Specialized (mountain bike marketing manager and all round amazing bike rider) suggested a lot was done on the firmware side, so it might be that the hardware changes were primarily for sound, but the power is from firmware. If that's the case, then theoretically Spesh could offer updates to existing owners, though that reduces incentives for existing owners to upgrade to new bikes.
Updating the firmware yourself wouldn't be easy as the Spesh systems are generally well secured even if you could get hold of the firmware, though potentially a third party could offer a "tuning service" if they knew what they were doing and weren't treading on Spesh toes.
Edit: put better picture of original motor.
Do you possibly have service manual for Mahle SL1.1 motor? You look like the man of knowledge I cant find any reasonable info on internet and just found this thread- which looks like most detailed info about those engines in whole internet I have 1.1. engine with mechanical issue (I thing clutch bearing is skipping) and where I live - nobody is repairing those motors- so I want to have a look myself- and trying to avoid big mistakes Cheeers. R