RC10Talk - The Net's Largest Vintage R/C Community

I came across a nice group of brushed motors from a dirt oval racer and there was a CAM super stock motor with some uniquely cut brushes. The sides were narrowed to allow the face to offset for more timing advance. I think it's really cool! I guess in racing, if you aren't cheating you aren't trying hard enough.
.

While it would increase timing, it would decrease current capacity and brush stability.

I didn't claim it was perfect, but I think the approach is very innovative. Personally I'd worry about it cracking and the end breaking off.

One of the modified motors in the lot had significantly advanced timing and was a screamer. However it also got hot real fast. It would have been a beast like that in a drag racer for short burst runs, but I turned it back to some reasonable mild timing to keep it from destroying itself.

Very cool! Never seen that before. As far as I recall...and could be completely wrong...but I ran plenty of timed/cut brushes, common on stock motors. But they were cut opposite from that.

There was lots of brush cutting going on back in the day. Several companies sold precut brushes and brush cutting machines were also a thing so you could cut your own. Everything from slotted brushes for more cooling to holes drilled up the center to stuff with cotton for comm drops.....