Thanks, everybody.

I need rollerskis for training and being in Bay Area I would use them
a lot as preparation for snow (6hr. away from here even in winter!).
And I can rollerski
practicly of my porch (next to Pebble Beach - no traffic, good road
w/rolling
hills along the Pacific)

But at the same time I want to organize some kinde of racing and at
least not to
loose skiing frends during summer.

Local outdoor speedskating races can let rollerskiers to participate.
They are looking for more people and nothing is wrong to have
rollerski category. In fact this is way better than wait for Rollerski
Federation to acknowlege California existence. They are too busy with
Turkey (you know, another Scandinavian country) and stuff.

So, my idea is to use racing rollerskis (and the same wheels I use for
skates)
for training and just slow them down with reducers, short bushings or
rubber
rings or use "dead" skating wheels, 100mm scooter wheels ets. or even
80mm wheels.

Melted wheel hubs is new phenomena to me - probably "shot" bearings
more than load (there are 2-wheels skates and they work OK).
Some new skating wheels have carbon or Alu. hub, so no sweat, they
will not melt.

If anybody is interested in new generation 100mm skating wheels
presumably applicable for rollerskis I should know thing or two.