Found the new 7 HV motor

[Lighty]

So is this motor a 485kv and not the stated 510kv?

If thats the case maybe I need a 15 tooth pinion to run 2000-2100?

I pulled this off another thread.

470kv motor 80% / 90%pwm
14t = 1750 / 1950
15t = 1900 / 2100
16t = 2000 / 2250

Here are a few others:

500kv motor 80% / 90%pwm
14t = 1850 / 2100
15t = 2000 / 2250
16t = 2150 / 2400

515kv motor 80% / 90% pwm
14t = 1950 / 2150
15t = 2050 / 2300
16t = 2200 / 2450

[apostolosnt]

I've measured the 4926 at 485kv exactly as belcom has, using a different method (unloaded test run). My handwound 1.6mm 13 turn YY should be by calculation 550kv (based on stock 510kv 14 turn YY) but it ended up being 520kv which also shows that stock is around 485kv.

BUT kv measurement is not an absolute standard. If you change ESC and timing you get slightly different numbers.
The 520kv rewound motor at 8khz, if you put it on a jive you get 507kv. So you see my point...

In any case the best way to decide your pinion is to set your desired throttle to govern properly (usually pwm ~80%) and actually measure rpm, because other things affect the true rpm as battery strength (a weak bat will have large voltage drop under load so you'll end up with lower rpm).

From my data also you are correct: you need 15T to govern properly 2000-2100 on stock 4926 and a good set of batteries.

[Lighty]

what does he mean when he's talking about 80% / 90%pwm?

[apostolosnt]

Originally Posted by Lighty

what does he mean when he's talking about 80% / 90%pwm?

PWM is the actual throttle level in the esc. It relates to how much of the time the current is on. That is how the esc regulates the speed of the motor. There is a great thread in the Tech Room for escs.
PWM is NOT necessarily the same as throttle level in your Tx. e.g. Jive actual throttle is calculated as 50% + (Tx Throttle%) / 2
So if you set your flat curve at 60% that will be 50+60/2=80% actual throttle in a jive.
Other escs have a direct relation between tx number and esc pwm.
Also there may be a difference depending on endpoints in the Tx. So if you set a curve and change endpoints then the relation between Tx value and actual PWM changes.