In Cleveland we setup every motor with the 767 brush. The motors there were the "New" Trinity motor. The only difference was that it was chrome instead of green and had 4 magnets. Which only means ya gear them down a little.
We put 767 brush on all of them with green springs. Rollouts down there were about 1.60...... Most gear a Monster motor with 1.70 or so, which is a tooth or two up.
There are other tricks you can do........ such as seeing how the brushes are wearing and too align the hoods...... you could get a .1255" reamer to free up the arm shafts, .126 will make it sloppy.......
Make sure your batteries are treated right between runs IE: discharge..... then tray them........ take out as soon as lights go out....... charge at 6 to 7 amps.
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