A ordinary bike wheel is to prefere, since the axle goes trough the hub,
so your platforms are connected to each other.
If you use a wheel with a unicycle hub, the platformst won't be in
contact, and they may spin with the wheel since there is only half the
weight on the bearing..
Use a regular bike wheel, preferibly with from a BMX, with longer a
longer and stronger axle.
But any bikewheel would probably work out fine, for awhile at least.
--
lleberg - Level 4 unicyclist
I <3 my unicycle!
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