It might have something to do with power supply in certain locations....dropping voltage. But if that's the case, it might affect it in DCC less since the full voltage is always applied to the rails, even if it is reduced somewhat. Can you meter the rails under the loco with the loco stopped at the weak spots? It might be instructive. Try not to put any pressure on the rails with the probes; just make contact with the tips. You don't want any confounding variables such as altering the geometry of the rails relative to each other.
I have a Proto 2000 GP9 That I was having some problems with(Cracked gears, wiring issues). I have fixed all of the issues and installed a DCC decoder. when I run it on the DCC club layout, I runs fine. but when I run it on my DC layout, I jerks, as in it will run slow, than faster, than slow again. Is it because of the decoder, or the engine?
Harrison
Homeschooler living In upstate NY a.k.a Northern NY.
Modeling the D&H in 1978.
Route of the famous "Montreal Limited"
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