

NSP (Vermont)
Joined Aug 2000
2,695 Posts

New! MicRotex motors are here!
Got in three motors as samples to bring to WRAM Show!
I have some of the specs so here they are: MicroTex 20/5/16 Efficiency max 79% 6A with max at 8amp Rm .284 weight: 24 gms Prop size 7 x 3.88 x 4 with 8 x 4 prop 280 gms thrust @7.8 A with 7 x 3.8 prop 232 gms thrust @ 5.3 amps 



NSP (Vermont)
Joined Aug 2000
2,695 Posts

MicRotex 20/5/18
Efficienct 79% Max amps 6 with peak at 8 Rm .314 ohms weight 24 gms prop 8 x 4, 9 x5 With 2li_poly cells with 7 x 3.8 prop 325gms thrust @5.1 amps with 8 x 4 prop 370 gms thrust @7.6 amps with 9 x 5 prop 300 gms thrust @ 8.8 amps 


NSP (Vermont)
Joined Aug 2000
2,695 Posts

MicRotex 20/5/14
24 gms efficiency 79% max amps 6 with peak at 8 Rm .192 ohms 2 cellLipoly with 7 x 3.8 prop 232 gms thrust @ 5.3 amps with 8 x 4 prop 280 gms thrust @7.8 amps If anybody is able to convert these figures to Kv, Io and Rm (we know that one already) I will give them a free MicRotex motor. This is the first person with complete and ACCURATE info. on all 3 motors. In the meantime. If you want to see one come to our booth at the WRAM show this weekend. 



Sal those figures look very promising, I wish I could convert 'em as I would pop one of those on a plane in a heartbeat.
I'm having a hard time distinguishing between the 15 and the 14 as the specs look identical. But what blows me away is the 18 with over 13 ounces of thrust on 2 cells with a 9x5 prop and 7.6 amps. That is incredible. If I make up a few figures and they look good can I at least get a discount?? :) Ron 



Don't know where Sal is getting his numbers, but they're not the same as what is listed on the Rotex web site. The site also lists the type of props that were used in the tests.
http://www.modelweb.cz/freeair/motory.htm 



Sal: Why not just put 2 pieces of tape on the bell and use an RPM meter to find the Kv (divide the RPM by the voltage at the ESC), then measure the amperage with a wattmeter or Sears clamp meter on for the Io. That'd be super simple and take less than 5 min.
Jim 



Hi Sal, I just sent you an email in the hope of being one of the first in line for a 20/5/18. [Ordered February 2]
I am puzzled by the posted data for the 20/5/18  how is it that a 9x5 at 8.8A is producing LESS thrust (only 300g) than an 8x4 at 7.6A (370g)? I assume, just from the 8x4 and 9x5, that those are GWS HD props? Cheers, Phil 



Nope, they're not the numbers for the 20/8/18.
Sal shows for the 20/5/18 With 2li_poly cells with 9 x 5 prop 300 gms thrust @ 8.8 amps  Web site shows  For the 20/5/18 With 2 li poly cells with 9 x 5 prop 250 gms thrust @ 6.0 amps With 3 li poly cells with 8 x 4.3 prop 350 gms thrust @ 7.7 amps  For the 20/8/18 With 2 li poly cells with 9 x 5 prop 220 gms thrust @ 4.12 amps With 3 li poly cells with 9 x 5 prop 310 gms thrust @ 5.6 amps 



Sal  can you explain what the 20/5/15 is  that is the one that you have for sale on your website????
Are they / were they ever in stock? If not when do you expect to have them  and which model specifically will be in stock soonest  and which model will be shipped to those that ordered the 20/5/15? It seems that it would have been more honest to call that a preorder rather than imply that they are a stocked item. Please clear this up for us. 



I just knew that the 20/8 was 79% efficient and the 20/5 was 75%. I guess Sal's motors are different then.
So Sal, we need rpm to be able to calculate MotoCalc parameters. Unless we guess about the rpm required to produce the thrust. 
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