TR 42-40B 900kv Brushless Outrunner eq: 3520 AXi

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Customer Rated

Nov 21, 2011

Got this motor installed 25e hyperions first take off it start screeching sounds and up in the air try to do 3d and hover I throttle 20pcnt and half way throttle the motor stop? I let it fly and glide while the motor stop 3-second later throttle back the stick motor start running again, I am glad I am able to glide my plane than crashing it. I've called HK but not answering the phone really disappointed. I have bought many different motors but this one got it bad.

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Customer Rated

Nov 05, 2011

Hi all, bought this motor some time ago& havent used it yet but as others have found one bearting is suss. I noted that someone referred to boca bearings for replacement, well boca has these bearings they are:-MR695-ZZ & MR115-ZZ of (5x11x4mm) & (5x13x4mm). cost is around $5.00 for these two freight, so not bad in my opion, by the way Im using 4s lipo with 11x5.5 apc prop. develops around 485w @ 33amps/16v & with a cut down 12x6 apc develops 660w @16v/44amps also not bad, have fitted to the spitty also bought from HK, havent flown it yet had quite abit of customising to to fit retract servo/new housing for it. anyway cheers bainopf

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Customer Rated

Jun 03, 2011

I have the same screaming noise on but only on quick throttle up. If you do it slowly it does not do it. Since I have this on a 3D, I need the quick up & down. I have written HK to see what if anything they will do since this seems to be a known problem. Does anyone know what/where to bearing can be ordered, part numbers etc. Please post.



I did run a a watt test and got 320 watts with a 3000mah 30C discharge on an 11x6.5 prop. But with the screaming noise I did not run any more. Going to run a 12.6e test once I get this solved.

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Customer Rated

Jan 29, 2011

The good motor. Model Madness 2 1400cm, 1600??, 4S 2200ma, a propeller 13X4, a current 38?. Perfectly flies.

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Customer Rated

Dec 21, 2010

C est un trs bon moteur. Je le fais voler dans un discus de 2 mtres 60 avec une helice de 11 x8. La monte est de 30. Prevoir une helice de 14...

A acheter sans hesiter

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Customer Rated

Dec 16, 2010

My tests

4S 13X6 and 11X5, 5









http://www.youtube.com/watch?v=2ea-mmnkrZQ



http://www.youtube.com/watch?v=hH3PwQI0XcE







4S for this motor a lot.

I think only the 3S

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Customer Rated

Nov 07, 2010

Just got another testil.Ne not like what the weight, along with mounting 171g although it was stated 125g is probably no fixing.

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Customer Rated

Oct 31, 2010

Just used this as a replacement on my E-flite Apprentice. Motor bolted straight in, and give 7450 rpm at 22.5 amps. This is better than the original motor that gave 7050 at 24 amps. Nice!



See my detailed review at:



http://www.rcgroups.com/forums/showthread.php?t=915223&page=34

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Certified Buyer Rated

Oct 15, 2010

Very powerful motors. Much bigger than I expected. The shaft is a little soft, which bends if direct head-on coalition. Now looking for replacement shaft.

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Customer Rated

Sep 30, 2010

8 Minutes

That's how long it lasted! After the first flight the prop shaft was so tight it would hardly turn and it made some weird sounds while flying. Have already orded new bearings for it. BUT even if it cost five bucks if it don't work out of the box then it is not worth having!!!

TURNIGY should try some QC I would have paid $20 more if it had good bearings and been happy!