The N scale Fox Valley wheelsets are FINE wheel sets. They are intended for those in fiNescale with tighter track standards. For use with standard N scale trackwork, you'll need to use the additional trick of filling the frogway in with some hardening auto putty and clean out a set for the proper 'shelf' depth to let the flanges ride across the frog area.
-ed-
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-ed mccamey-
COSLAR RR -
http://www.coslar.us/NMRA Standards and Conformance Department
PROTO & FINE Scale Coordinator
I estimate I have about 5 pounds of coupler springs somewhere in the vicinity of my workbench.