Top speed and efficiency


#1

I calculated my speed, and it is this:
Top Speed
28.54 mph / 45.92 kph
Weighted Top Speed
19.97 mph / 32.15 kph

Is the weighted top speed accurate in real world? My understanding is that at such a speed load wouldn’t matter.


#2

Theoretical speed of the raptor is 26-27mph, and there have been people who have acheived that number, so yea, I’d say it’s possible to go the theoretical max.


#3

Wind resistance and friction is a big factor at high speeds.


#4

best way to find out is to get a speedo app for your smartphone, go find a long flat road, get in your tuck stance and burry the throttle. Be sure to tighten up your trucks first.


#5

don’t forget to wear only speedos as well. you know… for less wind resistance…


#6

and shave your legs too, it will give you an additional 3 HP


#7

But only if they are RED.
This will give you instant 20% speed boost according to @longhairedboy


#8

Its true. I also use red shrink tubing on my battery packs and red electrical tape wherever possible to increase performance in the electronics. I would highly recommend painting your legs red if you’re serious about increasing top end speed. And make sure you use a red razor to shave them first for the highest performance shaving experience.


#9

And no problem if you cut youself, red is still good.


#10

shave so hard you get cut everywhere and there is blood all over you.


#11

SPEED and POWER is worth to sacrifice some blood to lord SKATAN


#12

the power of Skatan compels me.


#13

What percentage of ‘‘efficiency’’ did you choose?

I think there are people who get closer to theoretical top speed, especially if they are lighter and not heavy.


#14

70 percent


#15

Ok, already though so… Well, I’ve run the calculations for 2 boards/setups using data from what people claimed their top speed and setup were. The speed was way higher… something more like 80-90 efficiency…

But you should also ask around… as I still have not completed my build yet and cannot give any data of the real world situation…

Btw - I like to use this calc:

http://217.118.128.188/tests/ev_calc.html

It also gives the ability to estimate motor rpm and motor amps (although, not so sure about the speed estimate)


#16

i have always reached my theoretical 100% efficiency max kph (calculated with 36V) in slight downhill slope scenarios (talking 5% slope max here) and never fallen short more than 2-3kph on my theoretical max on perfectly flat ground.

example with my current vanguard: 10S single SK6374 with 16/36T & 90mm tires, theoretical max 45kph, FOC max on straights 41kph, BLDC max on straights 43kph!


#17

The difference in max speed between FOC and BLDC seem to pretty negligible then.


#18

I have those speed trap things that measure speed and flash it on a display to get drivers to slow down.

For me 80% efficiency is accurate TS for flat ground. 23 mph flat ground.

FOC/Ollin Vesc
R-spec 190
8s
97 mm
16/36t


#19

could be the different voltage we use to calculate theoretical max speed. if I use 10S = 41.4V fully charged (in my case), my theoretical topspeed would be actually 52kph and then 43kph bldc topspeed is 82%. if I use 36V however, I got a theoretical max of 45kph and 43kph is 95%.


E-Toxx DirectDrive VS Trampa Vesc6 VS Leopard 8072-170kv VS Nowind
#20

yeah I use the nominal average to reflect top speed during most of the packs charge.

It would be great to get full voltage top speed all the time.