Wow -- that is a rather creative transfer of inline skate technology to
rollerskis.

Interesting that the PowerSlide brake looks to me like it may work better
for 120mm wheels than for 84mm.

Laurent Duparchy wrote
I've adapted it on my (homemade) rollerskis and it fits perfectly with
my 120 mm wheels, as you can see at
http://lo.dup.chez.tiscali.fr/index.html

I assume you've seen that other website with the photos showing how increase
the down-force on the brake pad by attaching a rope to the front of the
skate (or rollerski) and pulling up on it.

Ken