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Old Yesterday, 03:28 AM
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MotionRC and Grayson list the V2 as having a 3200kv motor.
That is probably even better suited to 4S and change to CS10 or XRP14 blade rotor.

I am sure someone along the way said 3300kv on the V2 - but it seems it is really 3200kv.
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Old Yesterday, 06:07 AM
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I've mentioned it on other threads and I guess there's not agreement on the subject. But I've seen a simple correlation between the C rating of a battery and the speed of the plane. The higher the C rating, the faster it goes. That is on the same plane comparing the same brand of batteries.
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Old Yesterday, 08:25 AM
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Quote:
Originally Posted by oldsneakers View Post
I've mentioned it on other threads and I guess there's not agreement on the subject. But I've seen a simple correlation between the C rating of a battery and the speed of the plane. The higher the C rating, the faster it goes. That is on the same plane comparing the same brand of batteries.
Is that perhaps just a factor of how much more sustained full thrust can be maintained?

I have raced motorcycles in the dim dark past and getting on the GAS early can make a difference of several mph's at the breaking zone - the fastest time is always going to be achieved by the amount of time spent at maximum possible propulsion.

A battery will drop off as it is pushed for amps and will likely provide more for longer the higher the C rating?? trade off would be weight.

I run several different rated 4S in my meteor and can't really tell the difference in speed but also have never had it measured or really been concerned to.

Interesting proposition never the less.
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Old Yesterday, 09:34 AM
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Higher C batteries have a lower Internal Resistance.
A battery and motor form a 'voltage divider' effectively, pretty well exactly as per two Resistors in series will, so the one with more resistance gets more voltage from that 'division'. Of course the motor (via ESC too) is higher resistance than the battery (internal resistance) so to gets the greater majority of the voltage.
But a higher IR battery (lower C) has a worse ratio of that, because the battery has more voltage used inside it.... so the motor runs at lower power. (lower volts at the motor, less Amps drawn, less Power resultant).
This is what the Voltage 'sag', drop, is....... when a load draws Current (Amps), that Resistance value has a Voltage across it - and the Higher Internal Resistance battery thus has more voltage 'across its Internal Resistance' and thus less across the motor.

Then you also have the fact that batteries 'degrade' as they are used - or even just over time/aging - and that degrading has the Internal Resistance get larger. So they 'sag', drop voltage, even more.... so the motor gets less....
So a high C 'good' battery has a better starting point than a lower C one. And both slide down their scale as they degrade....

The IR, and all that above, is also why the higher C (lower IR) battery can supply more Current in the first place - and still has more later on.... more than a lower C battery has.

And that is also why everyone's tests of motor/fan combos can be different to other people's tests. Even the same claimed "C" of any battery used can be different to another brand... and even a bit different to another same brand one... because that is really the Internal resistance, and the different values they can have from battery to battery. New... older... different brand...different C Rating in the first place.... treated different through their life... etc
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Old Yesterday, 12:51 PM
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I've mostly bought HK nano-tech batteries for a long time. I started with the 25C, then on to the 35C, then the 45C and now I just buy 60 & 65C batteries. I don't know if you'd see the changes with another brand. But it's been easy to see with these.
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Old Yesterday, 01:08 PM
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Originally Posted by oldsneakers View Post
I've mostly bought HK nano-tech batteries for a long time. I started with the 25C, then on to the 35C, then the 45C and now I just buy 60 & 65C batteries. I don't know if you'd see the changes with another brand. But it's been easy to see with these.
I bought all of the series of the nanos except the a-specs.
the 65c are by far the best batteries punching the most power.
ifyou treat them right they will also last. but they are indeed very sensitive to "overdischarging".
had 6 4400mah 65c 4s which I had in sets of 2 and I was flying a flyfly MB339 with an 8s setup.
All bought at the same time. some day I made a mistake and made my second flight with the first flight pack set and discharged them to 0%. I immediately charged them a bit and let them cool down before doing a full balance charge.
The batteries recovered and continued to use them for another 6 months but I noticed a significant power loss and my flight times were decreased. that MB was great for slow and low fly bys. my flight times were up to 6-7 minutes but with that set I could only fly 4 .

The other 2 sets continued to go strong for another 2 years.
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Old Yesterday, 03:48 PM
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I've done the same thing for different reasons. Running the batteries down to zero is the kiss of death. The puffing gets worse, flight times reduced. And then its final act, one cell won't charge right. So sad. Ha ha
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