if you remove the acc. pump on your Flat CR carb, the bike will die when the throttle is cracked from low engine speeds. since the slide is directly affected by throttle position, the motor will ingest a sudden and large amount of air during quick throttle openings. this causes a lean mixture and the engine will die. i know this because my bike had an unreliable and short pump squirt from the factory. i now have it shooting for about 0.5 seconds and it runs fantastic. the throttle can be hit from idle, and the engine will not bog or hesitate.
if Ferry runs a carb without a acc. pump, then im guessing it's some kind of CV carb. the slide position in a CV carb is controlled by engine vacume instead of throttle position, so it is possible. not sure why they changed the standard Kehin. oh, and it is easy to disconnect your acc. pump to see for yourself. probaly the easiest way is to remove the diaphram pushrod. access can be made via the diaphram assembly.