I’m currently in the process of gathering parts for my build and i’ve practically got everything i need. However, there’s one thing that’s bothering me, and that’s the speed of a single drive board. I’ve been browsing YouTube looking at various speed tests but in my opinion it doesn’t look like they’re actually going at a decent speed. It may just be the camera angle that messes with the perspective but i want to be absolutely sure that what i’m buying is going to work how i want it to work. So here’s the question, what would the specs of my motor, gear ratio, battery etc have to be in order to go at almost double the speed of the board in this video: https://www.youtube.com/watch?v=m3ySmFGMGzw without having to go with dual motors? Is it possible? I currently have decided to go with an 192kv Turnigy SK3 motor and two 5s lipos in series which from what i’ve read seems to be the best i can get. I might have missed something.
12s lipo, 280 kv, 12s ESC, 107 mm, 16/36 gearing. That will probably get you extremely fast speeds. http://calc.esk8.it/
You could use a different gearing to get even more speed. But you will have barely any torque, i would not recommend this for an offroad build.
Why do you need torque when you have speed? For example, if I saw a hill about 200meters in front of me couldn’t I just accelerate to a speed that will gather enough momentum to get me up the hill?
Also, wouldn’t this setup fry my ESC?
Well not always, if you do not have enough speed or torque the motors might not even have the capability to take you up a hill. Torque is also important in acceleration. Without torque your acceleration will be slower. With the setup I gave you should go faster then you will ever want.
So would you say that the setup I have currently (190kv, 10s, etc) is a good combination of torque and speed?
If you have inadequate torque, you’ll eventually slow down and overheat your motors, if not kill them. You also might have a hard time accelerating at a decent rate after lights and stop signs. Keep in mind the amount of current required increases exponentially as you go faster. You should aim for 30-35mph tops if you want speed to be efficient. 97mm wheels + 200kv motor + 10s + 16/36 will get you near 35mph.
190kv 10s is pretty much a gold standard in esk8
Yes, probably one of the most successful setups.
Would fry your VESC not ESC, like TB 120A Opto esc
@ArmandR and @Jinra both right. One to optimize speed exclusively, i.e. Overly at cost of torque. The other plenty of speed and better torque trade off. You can always tweak the pulleys gearing ratio, wheel size, battery spec, rider weight (harder lol) to increase speed or torque or whatever but best practice to start with proven build foundation like @Jinra specifies!
And I take it if I had 7 inch mountain board wheels I would get as much speed if not more?
You would think so, but no. Shift to pneummies changes the equation.
What would the equation be? I should have probably made it clear that I’m building a mountain board (for mainly flat canal paths)
you’ll want a bigger pulley for pneumatics which will decrease top speed given the same settings in other places. For example, Evolte GT uses 66T pulleys on pneumatics I believe.
(Edit). Actually remembering that thread was more about “why is my pneummie battrery consumption 2x my uro?” Lol
Correct sir, resulting in serious gearing ratio given same motor pulley!!
66T for both motor and wheel pully?!
no 15T for motor on the GT
Yet the evolve gt goes much faster compared to the speed of the board in the video I linked!