First some facts (using my calipers)....
A standup brush has a width of 0.145"
A laydown brush has a width of 0.185"
The Orion full round brush has a width of 0.155"
(FYI - Checkpoint uses round 0.170" width brushes)
So -- motors "fire" the coils for a duration that depends on the "wrap" of the brush, which is a direct result of the width of the brush and comm diameter. I don't bother to do the math, but it's all relative anyway...
Laydown motors get their RPM's from the advanced leading edge of the brush and from the longer duration the coils are triggered.
Standup motors show more torque since their retain the same contact surface of the brush, but at the cost of lower RPM since their leading edge is not as advanced. This is not a problem for modified motors, because adjustable timing allows for compensation for the leading edge disadvantage...
The Orion brush system is between standup and laydown brushes in their width, so they fall in between the two in fixed timing motors. However, don't be confused... For a fixed spec motors (fixed winds, etc., whether 23 or 27 turn), every change involves a tradeoff... In the case of Orion endbells, the result that a converted laydown motor will lose RPM as noted above... BUT-- what is important is POWER -- RPM simply dictate gearing. My testing with the Orion conversion for EPIC motors on a 19t Chameleon show that POWER is improved, but RPM do drop.. Simply gear up (larger pinion) to compensate and you have a STRONG motor! The improved power comes from improved efficiency from the ability to run softer springs and the smoother power deliever from the round brush leading/trailing edges... Maintenance is reduced as well....
"If you cannot win, make the one ahead of you break the record."
Biff Racing Team #420 (Ah... The "good old days"...)
The local indoor Offroad Track: The RC Race Barn
TLR22-3.0, TLR22T-2.0, TLR22SCT-1.0