Buzzcut, The risers are underneath the heli's and are not part of the helibar system, and are often used under stock C10 bars too. The risers do raise the bars up 1.25" and back toward the rider a little too.
Not real sure how to answer some of your questions due to the infinite adjustability of the Heli's not to mention the different dimensions of people! Here's some dimensions that may help, of the bars WITHOUT the risers for a direct comparo to the C10 OEM bars.
1 - straight line measurement to outside end of handgrip closest to rider, to the other handgrip.
2 - Line B - Top of fork tube to top inside of handgrip - along riser tube.
3 - Line C - Top of fork tube to top inside of handgrip - actual net vertical rise.
4 - 90 degree from bottom of key lock cylinder to the imaginary line running from A to A.
C10 OEM Heli's
1 - 25.0" ~26.0"
2 - 5.5" 7.0"
3 - 3.5" Varies
4 - 7.0" Up to 11" depending on Yellow pivot
Pivot Points:
Red - hand grip up or down
Green - hand grip front to back
Yellow - pivot for entire handlebar set
