For a ROAR based 19 Turn spec class for offroad racing, the only motor I believe that is legal is the newer Chameleon 2s with the crossed (mabuchi? ) style wrapped armatures. The other motors are hemi style wrapped armatures.
You may want to check the ROAR rules to confirm but I think that is correct as there was some discussion about this in the touring thread and the motor was stated to not be legal by an AE rep.
Are you planning to use this at a local level? If so, maybe discuss with the track owner and other drivers and get it down as to what motors will be legal for the track.
I think around here the popular 19T 2wd buggy class allows 19T motors as long as they have fixed timing at 24 degrees, so the guys run Reedy Quad Mags, Orion Elements, etc.
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