I think the smallest N scale pilot wheels are a bigger diameter than the Z wheels .
Check the pilot and tender wheel of the Bachmann 4-4-0's. They're both pretty durn small.
Wow 3rdRail you are correct . I will have to think these magnetic carriages over again .
Z wheels solid plastic .151
Bachmann 4-4-0 pilot plastic wheels metal axle .115
Bachmann 4-4-0 tender nickel wheels with a loose 1/2 axle .125
Flanges and treads large on the Bachmann's
I like the looks of the nickel but I need to axle them and insulate one side or use plastic for the axle
On the other hand , the pilot wheels are good to go .
Thanks for the info , maybe I will get this to actually be a runner .