Specna Batteries

[Cr0-Magnon]

Noob question I know but just picked up a Specna Arms SA-E01 Edge 2.0, which comes with a Gate Aster pre-installed. So far I'm pretty impressed and looking forward to skirmishing it. However whilst the trigger response seems fine, full-auto with a 7.4V lipo battery is pretty lacklustre at 11rps. I don't need 30rps or anything like that but would like to get the most out of it. Is 7.4V still recommended or would it be fine with a 11.1V?

[Sitting Duck]

With lame or low speed motors you gotta use 11.1v to get some snap

 

it won't go nutz, just about x 1.55 of what 7.4v speed/rof is

so 11rps on 7.4v will equate to around 17rps on similar spec 11.1v

might nudge 18rps if lucky as high tpa motors spin a bit more on 11.1v

and low tpa motors spin a little less that x1.55 on higher lipo's

 

it is to do with max efficiency/potential of motor being reached on different motors

but general rule of thumb is 11.1v is about 1.55 rof over a 7.4v lipo

 

it is going to be a 27tpa/18k motor in there say

so 11.1v will kick it up to say 28,000rpm

hardly insane rpm - so should be OK

though very fast motors like 40,000+ will spin ultra quick & brushes will wear faster

 

putting more juice/volts through it & higher rpm will cause the brushes to wear a bit more

but 18rps is not too mental imho & you need it somewhere near that as 11rps is too low

when in the thick of it all kicking off

 

and if/when eventually the old stock motor craps out, shove in a better one & 7.4v

 

TL-DR - YOU'LL BE FINE

[Cr0-Magnon]

Cheers!

[Cr0-Magnon]

@Sitting Duck - You weren't far off. With a fully charged 7.4, I was getting 750rpm. On a 11.1 it's bumped up to 1200. Which is about perfect for me and doesn't seem crazy fast.

[Sitting Duck]

1 hour ago, Cr0-Magnon said:

@Sitting Duck - You weren't far off. With a fully charged 7.4, I was getting 750rpm. On a 11.1 it's bumped up to 1200. Which is about perfect for me and doesn't seem crazy fast.

 

750rpm = 12.5rps

12.5 x 1.55 = 19.375rps

 

it is ROUGHLY about 55% on a 11.1v compared to a 7.4v

BUT different batteries/burst/capacity & brand can produce a bit of difference

 

As said torquey 27tpa on 11.1v you get a bit more than 55%

crazy speed motors a little bit less as there is a limit to motor performance

 

somewhere between 18rps to say 24rps is about right imho

without being a dick - plenty of snap without risk of getting slapped if go a bit nutz

twenties is plenty & all that

 

Cyma AK 028 with fixed stock, jam a schottky diode across motor

(if you can't be arsed to install a mosfet)

and just use 11.1v - snap without going too nutz or chucking loads of money at it

 

if/when she plays up, then consider upgrades & decent 7.4v

but 11.1v on lame motor (with diode/mosfet) is an easy cheap boost

 

just bought some of these last week when they were on offer at £6...

 

https://hobbyking.com/en_us/rhino-2200mah-3s-25c-lipo-battery-pack-w-xt60.html?wrh_pdp=1

 

fucking short balance lead but £6 - c'mon