fyi[:D][:D][:D][:D]
in running my new railking triplex engine-the engine started to derail coming off the turn on my gargraves switch tracks onto the straight section-i replaced the front spring-stiffer-but to no avail-still derailing-i used a caliper to measure the innner and outer diameters taking the readings and matching them against a 736 lionel engine i discoved that the mth engine’s front wheel outer dimension-outer wheel to outer wheel distance was 1.5 cm smaller-the 736 engine did not derail on the switch tracks-i used a small wheel puller and increased the distance on the front truck wheels of the mth engine to the same as the 736 and this stopped the derailing problem-i do not know if this is only pertains to gargraves switches or other brands but i only am using gargraves switches-both the mth and 736 lionel engines are both 2 wheel front truck design-i had a similar problem with my premier triplex on a different loop and performed the same change with the same results-this is just a fyi-if anyone is having similar problems, check the switch track first then the front truck wheel outer dimension.