what to expect when switching between 11.1v and 7.4v batteries

[mjr_larkin]

I'm still trying to figure out the basics of how headspeed is effected by the battery voltage rating.

What kind of differences will I see between 7.4v vs 11.1v batteries in this heli?

[Buzzkill]

You'll see a dramatic increase in head speed, weight and heat with the 3 cell.

[mjr_larkin]

that's not necessarily the case, a 3S battery with a 14T pinion motor running at 3300kv is cooler, more efficient and more powerful (reportedly) than the stock 4800kv with 2S.

that being said, what i'm wondering is the difference between 11.1v and 7.4v or is it the case that you just assume all 3S are 11.1v?

[edit] The heligawds (helifreak users) have learned me up good. There is no such thing as a 7.4v 3S, all 3S lippos are in fact 11.1v. Going to a 2S with my motor will result in crap headspeed with the given pinion. All is right with the world. Let us be still.

[rotorhead58d]

if there is a 3s 7.4v battery, i'd like to see it.

[Buzzkill]

I asumed he was using the stock motor and pinion. All things being the same, a 3S will produce higher head speeds than a 2S.

[Jafa]

The motor produces 3800rpm per volt
If you give it more volts it will spin faster

The headspeed will certainly increase
but not as much as the motor due to reduction gearing

[danjoy25]

Can you use the stock motor, pinion and esc with a 3s pack? If not, whats the bees and knees for a 3s setup. I run a Trex 450 with 3400rpm Headspead so I want the smooth transition with the Gaui when I get one. LOl!

[psindrup]

The headspeed will certainly increase
but not as much as the motor due to reduction gearing

Relatively it will.
If the motor increases its RPM with 50% (from 2s to 3s) so will the head speed.

Peter

[Jafa]

You need a 9 or 10 T pinion for 3S

[mjr_larkin]

Or a 3300kV rated motor with 14 or 15 T pinion

[danjoy25]

Or a 3300kV rated motor with 14 or 15 T pinion

So where can I get this type of motor? Can you guys also suggest where to get pinions?

[t-driver]

So where can I get this type of motor? Can you guys also suggest where to get pinions?

http://www.elemodel.com/shopen/html/product_1335.html (http://www.elemodel.com/shopen/html/product_1335.html)
http://www.elemodel.com/shopen/html/product_1381.html (http://www.elemodel.com/shopen/html/product_1381.html)

i've both of them, they actually the same but one has a fan.
with a 12T and 3S 910 pack i get 11-12 minutes flight time.
and of cause incredible torque.:Bang

[rotorhead58d]

http://flying-hobby.com/catalog/product_info.php?cPath=18_76&products_id=2313

[t-driver]

http://flying-hobby.com/catalog/product_info.php?cPath=18_76&products_id=2313

this motor is "2S recommended".

[rotorhead58d]

at one part in the description is says 2-3 cell lipo, and the other it says 2s...flip a coin?

are you after insane headspeed, or what? what is your reason for wanting to go 3s? just curious.:confused:

[t-driver]

at one part in the description is says 2-3 cell lipo, and the other it says 2s...flip a coin?

are you after insane headspeed, or what? what is your reason for wanting to go 3s? just curious.:confused:

i have too many 3s lipos from my previous heli,a DF64C.
the heli is gone now but i still got the lipos......

[rotorhead58d]

this heli is so delicate. you really have to be a good pilot to fly this thing. i just think that a 3S setup will really wear the ball links, and the tail. the head is easily damaged too.:(

[t-driver]

this heli is so delicate. you really have to be a good pilot to fly this thing. i just think that a 3S setup will really wear the ball links, and the tail. the head is easily damaged too.:(

at first look this would be the case but a efficient 3S motor with a good pinion choice,
that won't add too much head speed (if any) ,and everything setup right,
would do more good than bad. for ones flight time is increased a lot.
the added weight add some stability, (must be as closest to the rotor as possible,to avoid pendulum effect )
a side effect would be more torque.....

[rotorhead58d]

well good luck. i hope it works out for you. keep us posted

[danjoy25]

[U][COLOR=#810081][URL]i've both of them, they actually the same but one has a fan.
with a 12T and 3S 910 pack i get 11-12 minutes flight time.
and of cause incredible torque.:Bang


Thanks for the link to the motor. What about the pinions?

[mjr_larkin]

That's not the right motor, that's hte 5150kV rated one, you want the 3300 version:
http://flying-hobby.com/catalog/product_info.php?cPath=18_76&products_id=369

[t-driver]

Thanks for the link to the motor. What about the pinions?

www.radicalrc.com (http://www.radicalrc.com)
http://www.allerc.com/product_info.php?products_id=1487

you need the 64 pitch or 0.4 modul, 2.3mm shaft

[danjoy25]

Got my kit and a bunch of spares order now. I'm still going the 2s route but would like to know has anyone tried the stock esc/motor combo on 3s. Im thinking of just changing the 15t pinion to something smaller like a 9, 10 or 12 tooth pinion as I can get those in flying-hobby if for some reason I'm not happy with the 2s setup. I've got the lipos cover as well as Im getting 3 x Gaui 2s packs which I can easily convert to a 2 x 3s setup if needed.

[t-driver]

Got my kit and a bunch of spares order now. I'm still going the 2s route but would like to know has anyone tried the stock esc/motor combo on 3s. Im thinking of just changing the 15t pinion to something smaller like a 9, 10 or 12 tooth pinion as I can get those in flying-hobby if for some reason I'm not happy with the 2s setup. I've got the lipos cover as well as Im getting 3 x Gaui 2s packs which I can easily convert to a 2 x 3s setup if needed.

as far as i know 2S is all you need.
i personally never tried 2S, i run on 3S with a 12 pinion.
awesome climbouts....:Bang