Thoughts on which way to go.. lipo or 16s


So I’ve got a 12s5p with 205kv radium 85’s running 150 m 70 b amps in the composite, but I want more power. Would the 205kv motors handle the 16s5p pack from my tomiboi? Erpm is apparently fine for a spare d75 i have.

Was thinking either the battery swap and a new pack for the 4wd or 4 7s lipos to go into the composite for 14s2p.

Not fussed on range just want fast.
Wwyd?

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So what are you really looking for? Speed or acceleration? Is the battery bottlenecking your 4wd build?
Cause if 4 motors dsn’t do if for you I donno bruh, jump off a plane or something? xD

16S might be a little too much for the 205KV motors, they’ll heat up quickly.

Radium’s recommendation is 151kv. I’m in the process of building a 16S pack that I intend on running with 173kv motors - and am keen to see how they hold up.

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I still think the top box adding p groups and staying 12s like you had it a while back.

I know you said you didnt like the extra weight but you need to give yourself time to adjust.

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I ran 205kv 16s 140 motor amps. Never had thermal issues, but I had a 6.43:1 ratio drive

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might be obvious to most but thermals on the motor has very little to do with the voltage (unless more spin = more mechanical wear = more heat).

generally Pf = R x I^2 is a very good indicator of resistive power dissipation.

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Resistive power loss is probably the biggest loss and heat producer and limiter of the motor’s power as we use them on a board with little wheels and like a 3:1 but I think with some setups switching losses (hysteresis and Eddy currents) can add up with how fast the motor is spun and can be close to resistive losses if not more and that’s likely a good thing.

Ideally you’d want half resistive losses and half switching and that will keep your motor coolest with most power, so using a high kv and high voltage and biggest gear ratio possible is likely ideal for keeping the motor cool, and possibly giving the most torque.

@Evwan whats ur no-load loss at highest speed with that high kv and voltage? At what erpm?

The 4wd is 16s 173kv. It runs like a peach. I’ve never had thermal issues with escs or motors. Its just a little too much for the 5p.

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That was still 16s with the top box. I’m not writing it off but if I end up using the 16s5p in the composite like your old setup I may try 16s2p lipos in the 4wd. Was talking to yogajitsu and he runs his 12s2p 4wd 120amps a corner with no sag apparently

No that 4wd is fast af :sweat_smile: the 4 motors are a little much for the 5p. Since I dropped a motor tooth to 15-72 it’s bearable though. I just like to make as much use of the gear I have as I can.

The 2wd is the one that’s underwhelming.

I’d go 16s if it were me cause ssssssssssnek

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dunno, its high but i used to cruise at duty cycle current limit (88-90% duty cycle) for miles at a time and my motors never got above 75C, which is tame for radium motors. They just cool so well

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Which esc did you have 140 amps at 16s? Must have been a quick setup?

Makerx d75 batch1 till it died on me. Board was nutty

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You mean at the current limit (140!?) and that high duty cycle? That sounds like huge wattage

Nah amperage is low when I’m cruising at top speed like that ofc. 6kw on that setup. 10 on my current setup

140 motor/50 batt 16s

Now I’m 140 motor/80 batt 18s

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Makes me think I’ll need a d100s

16s5p and 173kv at 110 amps ran great but I’d assume the 205kv are going to need more amps.

Damn this expensive hobby.

I’ve got a j2 ubox that that I could run in trap at high amps but I may be playing with :fire:

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