PC
Jul 19, 2003, 04:01 AM
I have recently swapped the motor of my Hummingbird from the crappy stock
motor to the Speed 300 motor rated at 6 Volts. I am not sure what
difference there is from the 6 Volt version of the Speed 300 and the 7.2
Volt version, but the difference it makes from the stock motor is
amazing.
After I did the motor swap, the first thing I noticed when taking off was
the immense torque the new motor made. I had to literally move the tail
rotor trimmer on the TX from one side to the other, and even then the
tail rotor still couldn't stop the heli from spinning.
I was using a 12 tooth pinion gear on the motor. I tried reducing the
pitch of the blades to almost zero; they looked flat, but the speed of
the rotor head was whizzing round so fast I could hardly see the blades
at all, but reduced the torque enough for the tail rotor to keep the
spinning under control.
It still took off with a lot of acceleration at about 1/4 throttle with
the blade pitch so low, and that totally amazed me because I needed about
3/4 throttle when I was using the stock motor even with a large blade
pitch. After about 1 minute of flying I landed it and touched the motor.
OUCH! That thing was HOT!!! I decided that was not very healthy for it
(and my finger - hehe!) so I tried a 10 tooth pinion. This time the thing
didn't get quite as hot, but still not good enough. I then tried an 8
tooth pinion, and it now seems to be about right, because it doesn't get
too hot even after about 5 minutes of flight. The head speed is waaaaay
higher than it used to be with the stock motor.
I'm just wondering though, is my 6V Speed 300 still being overstressed
running off an 8.4 Volt pack? I can't measure the actual voltage across
the motor when flying it, so I don't know what the real voltage is across
the motor. I am wondering whether anyone else here has tried using the 6
Volt version and the 7.2 Volt version and know how long they last, and
difference in life-span??? I'm fed up of the stock motor burning out, so
I want something to LAST!!!
Thankyou for any help!
motor to the Speed 300 motor rated at 6 Volts. I am not sure what
difference there is from the 6 Volt version of the Speed 300 and the 7.2
Volt version, but the difference it makes from the stock motor is
amazing.
After I did the motor swap, the first thing I noticed when taking off was
the immense torque the new motor made. I had to literally move the tail
rotor trimmer on the TX from one side to the other, and even then the
tail rotor still couldn't stop the heli from spinning.
I was using a 12 tooth pinion gear on the motor. I tried reducing the
pitch of the blades to almost zero; they looked flat, but the speed of
the rotor head was whizzing round so fast I could hardly see the blades
at all, but reduced the torque enough for the tail rotor to keep the
spinning under control.
It still took off with a lot of acceleration at about 1/4 throttle with
the blade pitch so low, and that totally amazed me because I needed about
3/4 throttle when I was using the stock motor even with a large blade
pitch. After about 1 minute of flying I landed it and touched the motor.
OUCH! That thing was HOT!!! I decided that was not very healthy for it
(and my finger - hehe!) so I tried a 10 tooth pinion. This time the thing
didn't get quite as hot, but still not good enough. I then tried an 8
tooth pinion, and it now seems to be about right, because it doesn't get
too hot even after about 5 minutes of flight. The head speed is waaaaay
higher than it used to be with the stock motor.
I'm just wondering though, is my 6V Speed 300 still being overstressed
running off an 8.4 Volt pack? I can't measure the actual voltage across
the motor when flying it, so I don't know what the real voltage is across
the motor. I am wondering whether anyone else here has tried using the 6
Volt version and the 7.2 Volt version and know how long they last, and
difference in life-span??? I'm fed up of the stock motor burning out, so
I want something to LAST!!!
Thankyou for any help!