Well, first thing I would do is narrow the brushes to standard size, or as close as you can get them. I would run about 18 deg of timing and gear it about 28/100 with around a 1.80" tire.
I would run the crosscut 99 brush and with the 1.88" tire I would gear down a tooth to 27/100. Perhaps a tooth or two lower since it is a double flatwire. Hang on, it should rip.
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