| Sorry can't help you on the cylinder bit other than its to do with the angle the lever pushes the master cylinder, could do with a good reference article to try and understand this a bit better as well.
at the caliper end its the way it mounts, radial mounts onto posts behind the fork leg, normal fits to the side of the fork leg , on a mountain bike fork we refer to radial as post mount or Manitou type. Its claimed to be a better way of fixing. | 
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