Originally Posted by
velotnt
There isn't any slipping but I think you brought up a good point that may be what i'm referring to. I think it's likely the ratcheting mechanism as there is just that little bit of delay that bugs me. Is there a way to adjust or reduce that delay?
From what you describe,I suspect you're talking about normal engagement delay in the ratchet mechanism. This is determined by the ratchet's design, specifically the number of engagements per revolution. As a rule, larger ratchet rings have more steps per revolution, so odds are an external freewheel would have more engagements per revolution and therefore quicker engagement than the smaller internal ratchet of a freehub.
If you back pedal one cassette revolution (note rear sprocket teeth, and count that many chain links of movement) you can determine the fineness of the ratchet. You can also back pedal slowly until the freehub clicks, then note the amount of pedal movement until the next click. The gear ratio determines how far the crank will move for any amount of rear hub dwell, so even if the ratchets are identical, a higher gear will seem to have coarser dwell.