Explain these numbers to me

[Interceptor]

Ok, I have two stock motors here. Here is the sticker info on the side of the cans:
Green Machine 3 Pro
RPM 19,823 @5.0V
Power 65W @ 10.6K
Eff 48.6% @13.0K
Torque 103.0 Nmm
PN 9427

Epic
RPM 22,115
Power 64W @11.2K
Eff 43.1% @ 15.3K
Torque 98.1 Nmm

I've been away a while and I forgot all of this stuff! Which is the better motor?

[Neon_Dave]

Depends for what. Based on the specs, the Green Machine produces more torque and power at a better efficiency, while the Epic has more RPM.

:D

[highroller]

Either one would be decent, those are the dyno numbers that are stuck to the Pro version motors. In most instances with some personal tuning those numbers can be improved.
In use you are likely to get close to the same results from either by gearing the GM3 a tooth higher than the Epic. Typically I'm seeing that with all of Trinity motors the P2K2 uses the largest Pinion, while the Epic Roar and EpicX uses the smaller pinion of the bunch. P2K, P2k2, GM3, MS2,CO27, Epic Roar, EpicX.
I use a slave motor dyno, testing them at 5volts (4cell racing), 25amp load and seen Epic Roar in the 21-23,000 rpm, torque in the .349 and watts near .112 nmm, MS2 wear in the 19-21,000, torque in .389 -.408, watts in the .109 range. Most were standard off the shelf motors, some OEM (Putnam, Hyperform) tuned motors produced a little better results.

[MadScientist]

Numbers given are the max values for each item. Actual values derived and what units displayed are Dyno dependent. Different dynos will produce different outputs and as others have stated different test standards yield different results. Both labels appear to be tested at 5 VDC so you can compare numbers. Units tell you what is what. RPM is obvious, Watts is power, Nmm or inoz are torque. most labels come with Nmm values. Bigest thing is when comparing make sure you know the test standard, here it is 5 V. higher torque usually means lower rpm but higher gearing for same power motors.

I test Stock motors using both flywheel and slave motor dynos, these labels and numbers are most likley from flywheel type dyno.

Win, MadScientist

[Interceptor]

Ok, just picked up a new Co27, and the sticker on it says:
RPM 21,370 @5.0V
Power 65W@ 10.5K
Eff 45.7% @ 14.0K
Torque 100.3 Nmm

I think I will run this one.

[highroller]

Like I said don't put to much in those sticker numbers. With some minor tuning those numbers can be improved and you see better results in the end.
There will be no difference in the end of your total laps provided the motors are geared differently and correctly for whatever type of racing you are doing. I use the MS2, CO27, Epic Roar Stock, EpicX turning 53/54 laps in 4cell oval with either type, just that one might perform better on any given day.
For 4cell oval racing I used either the Putnam Green Shunt (pos), Blue shunt on (neg) or Reedy 767 with a hollow, shaving a little of the leading edge, slotted cuts depending on amp draw or dyno readings. For springs Trinity Red (Pos), Green (Neg) for a starting spring tension. Disassemble the motor completely as we are going to prep some parts before putting them back. Chuck the armature in a drill or Dremel, apply some chrome polish to a rag and polish the output shaft, then the shaft on commutator end - be careful not to get any polish or nicks on comm. Use an old stock armature or 1/8 inch rod, with endbell loosely attached spin the armature inside motor to break in bushings (do not oil bushings at this time). Spin test the motor armature by installing back in can with no shims or washers to see in which direction the armature is being pulled - the magnets will always try to pull the armature towards the center and this will indicate the proper way to install the shims ( I used one teflon washer next to comm and metal/bronze of different thicknesses or the rest) that way spin test indicate that the side to side play is about limited to 1/32. Use an old set of brushes to determine if brushhood require aligning, color the face with a red or silver marker to determine the wear. Brush should wear directly down the center, try twisting brush hood in the opposite direction that brush wear indicates.
Finish up final installation and breakin of brushes normally done at 2volts for 1-3.5 minutes. For lubing bushing 1 drop of Marvel Mystery Oil, 3in1 or Pro Long (oil treatment). If you have access to a comm true, perform a light skim cut of the comm after brush breakin.
Have you used any of the motors you given the examples of the dynos numbers from. Which Epic motor do you have Epic Roar Stock or Epic X, my hunch is it's a Epic Roar or Quad (which is not legal if track uses a ROAR motor rules. The thing to getting close to the same results will be in gearing, the GM will use the higher pinion gear, CO27 in between the Epic and GM3.
The reason for the slight differences in rpm and torque output between them is not really one motor being better or yielding better results it has to due with the armature. The Epics -Roar Stock and X the armture stack lamenations are thinner than those used on the Monster Stock and Co27, The GM3 were narrower compared to the P2K2 but not as thin as the MS2.
Sometimes if you look only at rpm and torque, even watts, the numbers can be misleading in determining which motor might be best.

[luvesia]

:teacher: Does any one know if i switch a orion
pro bb armature in a reedy pl can will
this rob my performance? the reedy
arm is beat up pretty bad thats why
im switchin out. :teacher:

[luvesia]

do u know if reedys kr has good specs?