Comment by eduardo on October 27, 2012 at 7:41pm

Hey man ... this is a good motor as the DT750 but it use very small bearings.

i used DT750 in my OCTO 2 years ago.

All bearings presented problem after few month´s.

Comment by Nick Goodey on October 27, 2012 at 9:45pm

I have a tricopter with 700's nice robust motor as I have crashed my set on two frames and they are still going strong  Electrically they are quite good also

Comment by Glenn M on October 30, 2012 at 8:39am

I had two dt750s die bearing related deaths within about 10 hours of non-crash use. Haven't used any since.

Comment by Nick Goodey on October 30, 2012 at 11:51am

Good to know Hobby King have introduced a DT900 & DT1000 now also, wonder if they have improved bearings I bent a shaft on one of my DT700's in a crash but the bearing survived.

Comment by Alexey Kozin on November 1, 2012 at 4:23am

with dt750 /3s for multirotors must to be lage props

13*4.5 -15*4.5 carbon props for long-time fly

Comment by Nick Goodey on November 1, 2012 at 5:45am

I have a tri with DT700's turning 11 X 4.7 Slow flyers with a peak current of 11 amps @ 773 Grams of static thrust on a 3 cell lipo I have tried 12 X 3.8 gave lower rpm and from memory 880 grams at 14 amps so over the motor rating

Please see https://docs.google.com/spreadsheet/ccc?key=0AsmGA5b7qZ15dG0wcFNISH... for all my test data

Comment by Alexey Kozin on November 1, 2012 at 8:42am

dt750 tests

my

hextronics dt 750
ESC HK 30A ubec blue

gefman 12*4.5

3s bat
100g  0,94a  8,64 g/w
200g  1,76a  9,30 g/w
300g  2,65a  9,43 g/w
400g  4,15a  8.00 g/w

another test

http://www.bungymania.com/imageshome/includes3/motorperf1.php?id=119

max thrust 1959g

14.8v (4S)

12x5 FMS Folding

25.6 A

15 v

384 W

8520 t/mn

1959 g

Comment by Nick Goodey on November 1, 2012 at 12:28pm

Good to know 77 grams thrust per amp with your setup very efficient

I am getting 70 grams per amp my best efficiency is 7.03 G/W on the DT 700 with the 11 X 4.7 prop

My data has the DT850 better than the DT700 at 11 amps marginally but delivering 17% more thrust

Thanks for the data I shall read more tonight fromhttp://www.bungymania.com/imageshome/includes3/motorperf1.php?id=119

I am using the DT850 on a fixed wing plane and would need to move the motor to swing larger than an 11" prop

I May run a test on the DT850 on a 12 inch prop see what number I get and maybe move my FPV plane motor up higher

Comment by Nick Goodey on November 2, 2012 at 1:04am

DT850 Swinging 12 X 3.8 Power Test 

DT850 Swinging 12 X 3.8 Power Test

Looks like the 11 X 4.7 is better at 10 Amps around 820 Grams thrust. 

Prop                   AMPS   WATTS THRUST Thrust / Amps Range Minutes Volts         Discharge C Rate Grams / Watts
11 X 4.7      9.7    112.1 831        85.67          9.53            11.56    4.4091             7.41
12 X  3.8    10.3   112.7     821        79.71          8.97            10.94    4.6818             7.28


            

Posted 38 minutes ago by Nick Goodey

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