What they said.
With clipons, the fork tube slides through the mount, so the bars stay in the same place relative to the triples. You may or may not be able to mount them above the triple, depending on how much of the fork tube is sticking through.
With the stock risers, they mount above the fork tube, so they inherently will stay the same height from the ground, regardless of how far up or down you slide the triples. You need the blocks to provide more room for the top of the fork tube to stick up through the triple, while still allowing the riser to bolt onto the triple.
