I have a different issue with my 4th Schools Class purchase, Malvern, from the Collectors Club Spring 2020 Offers I have been running it in and it is apparent that it suffers from a tight spot but only when running round curves. My minimum radius is 300 mm, which the loco. should be able to take with ease. On the straight, running is good but on curves there is a rhythmic "rubbing" and at times the loco. can be seen slowing and surging again as the "tightness" is passed. I have tried running without the front bogie and that completely eliminates the noise, as well as any tendency to "surge"! I've also checked the bogie wheel back to back dimensions, in case they might be rubbing on the valve gear. I think that the problem might be because the leading driving axle does not move smoothly from side to side. It can be felt to almost grate in the bearing (or gearing?) as it is pushed from side to side. This is quite different to the easy movement on the rear driving axle. I have tried lubricating the axle on each side but am very wary about over-lubricating.
Regards
Doug
Regards
Doug
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