What does 'Level 8' output for amps normally? Without knowing that you're going to be guessing, and it will vary from manufacturer to manufacturer because ASI controllers are pretty much unique to each customer/manufacturer.
My own BAC800 - the model replaced by the 855 IIRC - will happily ramp up to a 60 amp continuous value no problem on my Cyc X1 Pro. That controller was a product of Electric Race Technologies and developed specifically for the Cyc motor. No clue given as to what yours is. ?
Gut level: a battery with a 40a peak BMS (you didn't say but assuming it is 52v or more) is inadequate. With 40a continuous it is also probably not enough. Peak reading is usually tripped IIRC after two seconds on a battery so your typical powerhouse BAC programming is easily able to do that and maintain it as a continuous value to boot.
You can't trust anything until you *know* what your controller specs are, I'm afraid. Since the BAC855 is a moving target that can easily be set up to exceed 40 amps, you need to find out from the people who programmed the controller.