The motor does look cool and is inexpensive and might make for a challenging project, but in the end, I doubt it will make a very good e-bike propulsion motor. The first issue, already mentioned, is that these motors are designed to output huge power, but only for a few minutes at a time. They overheat very quickly. You'll need some kind of heavy duty cooling system, not just a fan, more like 20psi compressed air pumped through the motor interior at all times. The high burst power design also makes these motors inefficient power guzzlers. The spec says 12v and 50 amps no load. So right there it's a 600 watt motor before it offers any useful propulsion power. You'll need to double up on your battery capacity, quadruple it if you add the air compressor. The last issue is the no load speed, 8000 rpm, which is fast. You would need to gear it down to about 27-40 times to match a 200-300 rpm wheel speed (15- 24 mph 26" bike wheel). A friction drive setup for this motor might be a better choice than a geared down chain drive setup. Since this is a 50 amp no load motor, expect 200- 300 amps peak current at start up, so you'll need high current wiring, batteries, and controller.
Also a casual search doesn't seem to turn up any success stories on using these motors for an e-bike propulsion. There are a few stories, but I've only read ones that don't end with a finished bike and a smiley face.
I don't want to be a downer, but I had seen these motors in the past and been excited about their power, but after doing the math, I don't think about them anymore. And after reading for hours about DIY motor conversions, I don't think about DIY motor conversions much anymore. Now, I think about hub motor kits.