Can a bike move on a frictionless surface?

No it would be very hard to ride it with out gavel

Yes. But it can't be set in motion by anything the rider does.

That must be the result of an external force.

Once the bike is moving on the frictionless surface, it can't speed up,

or slow down, or change direction.

Wait. I can get even more technical than that. Starting, stopping, or

any change in the bike's motion on the frictionless surface, has to be

accomplished by some means that discards mass ... like a rocket or

a jet engine, or by having the rider spit or throw his shoes.

And shalom, mazal, bracha, and happy omer #26 to you & yours.