[chrisguyw]

Most builders, (and all of the top ones)  of high end slot cars use non reduced diameter steel drill blank axles in sidewinder motor configurations that use motors with much much stronger magnets than the ones commonly used in 1/32 plastic cars.

Yes there is some magnetic attraction, but the frictional losses are very small, and quality steel drill blanks (non reduced) offer many benefits over the "reduced" axles from the plastic car manufacturers, as well as the various aluminum, carbon, and titanium axles to be found.

Cheers
Chris Walker