I run Bachmann's 70 tonners on Kato 8.5 and 7 inch radius. However they do not like the 6 inch radius stuff which is close to your 140 mm. However the Bachmann 44 tonners do well on it due to a shorter wheelbase. My three axle MDTs do run on it and they are about the same wheelbase as an 0-6-0. The 70 tonners have a longer wheelbase than the 44 tonners.
Thought that might be the case after reading that their S4 couldn't do it. Found a post where someone successfully tried various EMD switchers on the curves, so will probably go for one of those listed there. At least it looks like the 0-6-0 will work. Thanks.
The Tomix track is 5.5 inch rad. and I found this discussion on the web. https://www.modeltrainforum.com/showthread.php?t=25230 which talks about what will work on this track. There were made back when some 0-4-0 steamers that had a tender that had pick-up and that would be ideal. I am running Kato unitrack on my harbor to the piers and it is 6 inch. That area is the realm of the MDTs and the 44 tonners. The 70 tonners stay out on the 7 and 8.5 inch rad tracks of the mainline.
I got a couple of Tomix's 'Wide Tram' street trackage with 140mm and 173 mm curves (5.5" and 7.0") The Bachmann Peter Witt streetcars operate just fine on them. However, I have been told that the 103mm curves (4.0") is a no go. A 4.0 inch N scale curve scales out to about 53.3 feet which was very doable for prototype streetcars.
Your post just reminded me that I got two Tomix chassis stashed somewhere. I believe they are for a 17 meter prototype car. These were destined for a project to build West Penn traction number 700 cars that never got off the drawing board. I'll have to find them and resurrect that project. Would love to see these negotiate 4 inch radii curves
well, I think that I am about to start working on a streetcar paradise mini layout with a 4.75" or so radius.
