[Dave at Pelican Parts]

Hollow bars have a slightly smaller amount of spring force than solid bars. Very slight, in general...

A solid bar's effective spring rate goes up with the fourth power of the diameter, if all other things are equal. To get the effective spring rate of a hollow bar, figure it out as if it were solid. Then subtract the effective spring rate of a solid bar the size of the inner diameter of the hollow bar.

Example--a solid bar of 24mm in diameter versus a hollow bar 24mm in diameter with a 10mm hole in the middle.

Solid 24: 24^4 = 331776 (times whatever)
Hollow 24: 24^4 - 10^4 = 331776 - 10000 = 321776 (times the same "whatever" as the solid above) ; about 97% of the effective rate of the solid 24mm bar.

So they have a very slightly less spring rate, and the weight savings is very miniscule. Not worth it.

--DD