Turnigy Motor on the 450X

[Heli.Maniac]

Hey guys,
My stock 440 motor shaft is gone and has at least 1-1.5mm of side play so I won't trust it for tic tocs and 3D. I have ordered an 2221-6 on a 9t pinion, but it may take a month to arrive here and 1 month without my 450x is a nightmare
So, I went to my LHS and bought the turnigy 3700kv motor and put on an 11t pinion. First impression when I fitted it in the heli is that it's a direct replacement and no shims or spacers are needed for the pinion to align with the main gear. I put it on a hover only and the sound is defenately different than the 2 eflite 420 and 440 I had. On an 11 tooth pinion and from the sound, it has the same RPM on the head as the stock motor, maybe +-100RPM less. It's so windy today and probably will be tomorrow so I may not be able to try it on 3D, but I think that for 25$, it is a good quick solution while I am waiting on my Scorpion.

Regards,
Andrew

[Talesin]

Almost exactly 100, in fact. The optimal headspeed with the 440H (4200kV, 140:10) is 3330rpm, with a 3700kV 140:11 it works out to 3227 optimal. Not sure how the torque output will factor in though.

Incidentally, the 420 appears to run a 10t stock pinion on the 3D, and it's only a 3800kV motor. Might be worthwhile (if you can get a 10t pinion that will fit your Turnigy motor) and bog less on pitch changes, unless you're only doing sport flying.

Also, did you make sure the gear modulus on the pinion you're currently using is correct, compared with the main gear? If not, I'd watch them both VERY carefully for signs of unusual wear... possible that the different sound could be an improper mesh. Can't really say for certain though.

[Heli.Maniac]

Originally Posted by Talesin

Almost exactly 100, in fact. The optimal headspeed with the 440H (4200kV, 140:10) is 3330rpm, with a 3700kV 140:11 it works out to 3227 optimal. Not sure how the torque output will factor in though.

Incidentally, the 420 appears to run a 10t stock pinion on the 3D, and it's only a 3800kV motor. Might be worthwhile (if you can get a 10t pinion that will fit your Turnigy motor) and bog less on pitch changes, unless you're only doing sport flying.

Also, did you make sure the gear modulus on the pinion you're currently using is correct, compared with the main gear? If not, I'd watch them both VERY carefully for signs of unusual wear... possible that the different sound could be an improper mesh. Can't really say for certain though.

Yep I basically compared the Mod with the one on the stock pinion and they seem the same, although I 'll keep an eye on it. I don't think I will need a smaller pinion, I like tons of headspeed to get the most stability on the wind. On my B400 that has the 420 with 10t, it had low headspeed for my liking, but if tic tocs need very good collective management, I may go the 10t route. The turnigy motor has a 3.17mm shaft so finding a pinion is an easy task, unlike the stock motor that has that weird shaft. I also have the mesh, so that the main gear has ever so slightly play on the pinion. Now the heli has more like the 450 pro sound. Lets not forget that the turnigy motor is just a quick solution until the scorpion arrives. Hopefully I won't keep it in the heli for more than 3-4 weeks @ ~40 flights.

[Heli.Maniac]

UPDATE: Just gave it 2 flights and I have to say I didn't expect it to have the same power as the stock motor. On pitch pumps, it loses some headspeed just like the 440 motor, maybe a very tad less headspeed loss than the stock. I am pretty happy with it for the 25 or so $ I gave and it's going to keep me interested until the scorpion arrives. Flight time, in 4 minutes the battery comes warm and the ESC slightly warm, while the lipo goes down to 3,79V same as stock. Shouldn't it be more flight time than the stock motor now? As far as reliability goes, I think it's going to handle at least 100 flights like that, time will tell. Main gear teeth have absolutely no wear on them so the module of the pinion is good. And at last I don't have to wait 5 or so minutes until the motor is cool (the stock one always came down very warm almost hot), it took it ~2 minutes to cool down, or as I was putting the fresh battery on the heli. And I was trying to convince myself I would never put a Turnigy electronic (except LiPos) on any of my helis

[P.I.Engineer]

link to motor please

[Heli.Maniac]

It's this one: http://www.hobbyking.com/hobbyking/s...idProduct=8137. If you wait on the page for 5 or so minutes, it will offer it to you at 17$ if your interested in buying one.