Micro Trains Tips

F7B units:

The Microtrains "B" unit dumies often have terrific rolling resistance.

MT has come out with some shims that can help correct the problem. The "newer" units are supposed to have the shims, but they don't necessarily. There are still a lot of "old" B-units in the pipeline. If you want to know if one has the shims or not, look at the bottom of the trucks. There is a "window" in the center of the truck (it's there to provide clearance for the worm gear in the powered units). If there is a visible black bar going across the window inside the truck, then it has the shim in it. If you're not sure, you can carefully remove the truck side frames to check, as well. (thanks to This email address is being protected from spambots. You need JavaScript enabled to view it.)

Apparently you can get the shims from MT for 20 cents each, and a buck for shipping.

General tips for all MT locos with motor springs

The "motor springs" at a constant source of trouble. First, they are fragile, and often break, or go "sproing". Get a good pair of tweezers to deal with them.Even then, you can easily stretch out the loops on the ends of the springs. Buy some spares. Also, it's very easy to have the spring short against the chassis. In many cases, it is best to put some insulating material in the "slot" where the spring lives so it does not short. Finally, the tabs on the motor can easily short against the chassis, so positioning everything carefully, and adding some insulation will save you grief, especially when you convert to DCC.

Part numbers

motor springs - 981 95 022

brushes for F7 motor - 010 099 980 95012 2