I wrote: > For a typical 20-inch train wheel, "the coefficient... Bob Rice wrote: > A 20 inch RR wheel is pretty small, would be a streetcar wheel, > Passenger cars run 36" and lokies generally about 40". Don't > think the size makes much differance although in > my opinion a bigger wheel rolls easier?
My mistake. The book I was quoting actually said a 20 inch *radius*, so it would be a 40" wheel. And yes, the diameter is definitely part of the formula, so bigger does equal lower rolling resistance. Wonder what all those pennies on the track do to the rolling resistance? <g> _________ Jim Coate 1992 Chevy S10 1970's Elec-Trak http://www.eeevee.com
