450x Motor Replacement

[PaulCo]

Hello All,

My Eflite 440 motor self destructed today, would anyone know if a 450mx 3s Dominator motor be fine to use in my 450x.

Thanks.
Paul

[maddog7]

Be careful with pinions fella.
I bought a scorp 2221 6 for mine since the std rubbish 440 bearings have sh@t themselves but the shaft is 1/8 and small pinions on large shafts mean the teeth are too far apart for the maingear and it jumps the gear. The std motor is about 4200kv, if you use a lower KV and bigger pinion you might not get the pinion far enough away from the maingear. I'm looking into getting or making a 2mm shaft for my scorp, this would solve the issue I think.
D

[24sevenslacker]

I have just replaced mine with the eflite 450 motor. I just drilled out the standard pinion to 3.5 mm and it works just fine

[PaulCo]

I have just replaced mine with the eflite 450 motor. I just drilled out the standard pinion to 3.5 mm and it works just fine

Hello, thanks for info. Did you buy the motor recently - no one seems to have one in stock.

Paul

[24sevenslacker]

I ordered mine from the local shop 2 days ago, they rang HH while i was in there and got it sent through. Are you in the UK

[PaulCo]

I ordered mine from the local shop 2 days ago, they rang HH while i was in there and got it sent through. Are you in the UK

Yes, thanks - shall try to order one tomorrow.

[24sevenslacker]

No problem. Havnt flown it properly yet but it seems better than the 440

[JWhitby]

I replaced mine with a Turnigy HeliDrive SK3 Competition Series - 2839-3600kv motor and a 11 tooth pinion. I had to mod the frame slightly to get the motor wires to route nicely. It flies well.

[PaulCo]

Just ordered eflite 450 motor from local shop but he tells me that the standard esc is not good enough with the new motor, he has some 45amp perkins esc at reasonable price, he recons will be fine and a 9 tooth pinion should bring head speed to standard, - not as quick a fix as I was hoping, but got to get flying again, - missing it.

[24sevenslacker]

He is right, i have just had mine out tonight and it feels crap. Feels and sounds like the headspeed is really low. It also seems to be chewing my main gear which is odd because i meshed it correctly. Looks like ill be getting a better esc too

[tomatwalden]

Just ordered eflite 450 motor from local shop but he tells me that the standard esc is not good enough with the new motor, he has some 45amp perkins esc at reasonable price, he recons will be fine and a 9 tooth pinion should bring head speed to standard, - not as quick a fix as I was hoping, but got to get flying again, - missing it.

EDIT : I'm sure I've seen people using the e-flite 450H motor with the stock ESC mind .. ??

Never even heard of a "Perkins" ESC!? Are these designed for helicopters? You don't want a car or plane ESC on your heli, or one that you can't disable the brake.

This 45A from Hobbyking is £15 and is heli compatible ..

Hobbyking YEP 45A (2-6S) SBEC Brushless Speed Controller V2

[PaulCo]

Thanks for joining thread Tom. Apparently new eflite 450 motor runs at 45amp constant, stock esc is 35 amp, but yes I had not heard anyone mention they also upgraded esc with this motor ? Suggested esc is from J. Perkins distribution, not sure which esc he had in mind though, other than it was 45 amp rated, I have ordered the motor so shall honour that but am unsure what to do about the esc.

[tomatwalden]

ok guys. Just googled the two motors. The stock 440h motor is a 4200kv motor. The upgrade 450h motor is a 3600kv.

So, with the same % throttle value, the 450h WILL spin much slower. You need to change the pinion to suit the new gearing. Use Mr Mels calc to find the right pinion size for the job!

HTH. Tom.

[tomatwalden]

ok guys. Just googled the two motors. The stock 440h motor is a 4200kv motor. The upgrade 450h motor is a 3600kv.

So, with the same % throttle value, the 450h WILL spin much slower. You need to change the pinion to suit the new gearing. Use Mr Mels calc to find the right pinion size for the job!

HTH. Tom.

OK, now I've got a bit more time ... some values from Mr Mel's : MrMel headspeed calculator v3

Headspeeds with stock motor and pinion (140t/11t)

Result for calculation:
Estimated lowest voltage during flight: 10,23
Lowest RPM (due to voltage and efficiency) : 3038

(calculated for 100% throttle curve)
Hover RPM at beginning of flight: 3889
Hover RPM at middle of flight: 3581
Hover RPM at end of flight: 3457

Headspeeds with 450h motor and stock gearing.

Result for calculation:
Estimated lowest voltage during flight: 10,23
Lowest RPM (due to voltage and efficiency) : 2604

(calculated for 100% throttle curve)
Hover RPM at beginning of flight: 3333
Hover RPM at middle of flight: 3070
Hover RPM at end of flight: 2963

Results for 450h with a 13-tooth pinion

Result for calculation:
Estimated lowest voltage during flight: 10,23
Lowest RPM (due to voltage and efficiency) : 3077

(calculated for 100% throttle curve)
Hover RPM at beginning of flight: 3939
Hover RPM at middle of flight: 3628
Hover RPM at end of flight: 3501

So a 12 tooth (slightly lower HS) or 13 tooth (slightly higher HS) pinion is what you need to be able to get the best out of the 450h motor ..

[24sevenslacker]

Right. I get this now. Next question. Where can i find a 13t pinion to fit a 3.1mm shaft