Thread: Mini-Review Rimfire motors
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Old Sep 09, 2007, 02:10 PM
Diogenes2you is offline
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Originally Posted by Dr Kiwi
That is a very tough question:

The Axi 2212/26 weighs 57g and is said to be, variously, anywhere between 840Kv and 975Kv - 920Kv might be close, but perhaps it is a bit more?? It is rated (perhaps conservatively) at 12A max.

The Rimfire 28-30-950 weighs 54g and is said to be 950Kv and is rated at 14A/20A burst.

Direct comparison, even with the same prop, is still a bit of "apples" v. "oranges".

But take a look at this example - watts v. rpm, 10x6 GWS HD.

The graphs are very close indicating that each motor's "efficiency" in terms of rpm [and thus thrust (g)] per watt is much the same. Since the Axi curve is fractionally above that of the Rimfire, it could be considered marginally more efficient (but that is really splitting hairs).The Axi draws slightly more current than does the Rimfire, so it reaches a slightly higher rpm (and thus thrust) with this particular prop.

Now try this scenario:

If one could run the Rimfire at its continuous 14A rating, or even at its rated maximum (20A), without over-cooking then I suppose one could say the Rimfire is more powerful (than the Axi at its 12A limit) - but maybe the Axi (ignoring the recommended 12A limit) could be run at the same 20A current draw without over-cooking too! Then, since the motors seem to be equally "efficient", and on 11v both happened to be drawing 220W, and spinning the same prop at the same rpm, you would then have to say that the motors are equally powerful!

Now, I hope you are not even more confused!

Cheers, Phil
A bit too complex. So, if one has, say, a 22 ounce park flyer and would like to use one of these motors, which one would you suggest, and why?
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