Need some help before i make another mistake please

Hello, As the title says ive made some mistakes.

I initially purchased a trampa board with 6.5 inch wheels then decided to go for an undermount enclosure since my living circumstances changed and long story short it was too close to the ground for my liking so i got 200x50mm MBS wheels to replace my Urban carver wheels and i had already ordered my chain drive 35T/10T to go with this build running at a 3.5 ratio (35T/10T)

im considering upgrading to a helical gear drive instead though i was hoping to get 60-70kmh top speed but also keep a reasonable amount of torque since i live in the city i practically stop on every corner and my wowgo can get up to speed with the 10s2p battery but with a quick test running single drive with this setup 192kv SK8 motor with a 35/10T i had 0 torque. was difficult to push start with bindings but once i started moving i literlly had to hold full throttle to climb in speed, i had hooked up the metr app since i just got the module today since i blew one of my vesc yesterday doing a test run. this time i had monitored every step of the way through the app so i was only pulling an average of 8-12 amps

My question is will there be any difference in torque if i go 4:1 or 5:1 i plan on keeping the 200mm MBS wheels since they have good ground clearance but i would have liked to use the 165mm Trampa wheels since they felt a lot better for my daily use.

MY goal is to have a good amount of torque to throw me off the board but also maintain a decent high speed

1 Like

Yes; definitely.

Those goals are in direct opposition to one another.

Have you tried targeting your top speed at something like 27mph (43.4km/h) in the calculator linked above and finding the right gear ratio for that? That will maximise torque.

For pneumatics, you might want to lower the “efficiency” number to like 75%

4 Likes

I used to run a single sk3, I always had to go full throttle on hills. A sensored motor would help in startup and in going up hills. The lack in torque is a combination of the high Kv, the 3.5:1 gear ratio and the fact that u ran a single motor. Dual makes a big difference. The 5:1 gear ratio will definitly give you more torque. What battery do you run?

I run sk8 130kv motors on my trampa, 4.4:1 gear ratio and a 12s6p 30Q. The torque is amazing! I can reach a top speed of 40 km/h which is enough for me.

So you want enough torque to throw you off the board, but you also want to hit 40 miles per hour.
It’s usually one or the other…
I think if you shoot for like 31mph it will be easier.
Otherwise That’s a high end, dialed in build.

@DerelictRobot is the only person i can think of with a build remotely like what you’re looking for.

you first need dual motors for sure for what you are aiming, single motor just cant provide the power you want to have and also breaking is just bad and you need GOOD brakes when going fast. Than get a nice vesc/s like 2x vesc6 or 2x focbox single (I will sell some refurbished focboxes in a couple of weeks btw) and play a bit with the throttle curve and the positive ramping in vesc tool and maybe go 12s. With 1:5 gearing and 190kv in dual and 12s you will have enough torque to get that “punch” and the topspeed you are looking for. Maybe not 70km/h but did you ever ride that fast? Thats a loooooooooot of speed.

1 Like

Thanks, the battery is temporary I actually blew one of my foc boxes yesterday on a test run. I plan on changing to the flipsky duel vesc 6.6 I think it is. I have 192kv sk8 Motors that I plan on using with this build. I’m just running a single motor at the moment with my wowgo battery for testing with 10/35 iso 6 chain drive. Has no torque but I spoke with someone and they said it could be due to the max output of the battery being 30 amps. I have cells coming to build a 12s7p for this build with 30Q cells

The speed sounds like a lot but I top out my wowgo on hubs and it feels pretty slow to me. I need thr torque because I live in the city and stop at every corner almost due to lights. So torque for quick acceleration is a must but I also want a good top speed I would settle for 60kmh if the torque can do some dog nuts on the grass =)

I usually average 35-40kmh I got to about 45kmh with the single drive doing a test down a long strip since it was late and no cars on the road. I felt like there was more to push but there was just no torque for a single 192kv with 10/35

To what I assumed hub motors run a 1:1 ratio. So how is it my wowgo hubs have a good amount of torque and can push me from a stand still yet a single motor with 3.5 rTio can not using the same 10s2p Sanyo battery I did the test with?

Amp delivery, wheel dimension, rolling resistance from belt and rubber.

Theres a few reasons but these are the main ones.

I’m struggling to see why you need to go from a wowgo to 70kph though. There has to be some reasonable middle ground in there?

3 Likes

Want the power for future use, won’t need it now or any time soon but will save from having to upgrade in the future. And I’m a. It of a speed junky so I would probably top it out within a week of feeling comfortable with it.

With 192kV motors and 8" wheels don’t even think of using anything longer than 5:1 gearing.

1 Like

What would your recommendation be?

5:1 is what I would choose for a street build, lower for off road (close to 6:1)
That is assuming 190kV and 8" tires.

192kv 200mm Mbs tyres 12s7p

85-90% gets me very close to reality speed in that calculator.
Pneumatics.

1 Like

Use two different gear ratio

What do you mean? I’m looking at getting the Etox helical gear drive they come in 1:4 and 1:5

Mail him about your case. He’s likely to help you out and getting a Helical Gear Drive.:smiley:

Alright, I was also coming here for assistance to see what was causing issues with my setup and how to correct it =)

Here his mail adress: jens@e-toxx.com

Yep, that us what I shoot for to, I went with 5.33 dual.

1 Like

I have E-Toxx mini for MBS Matrix II trucks…1:5 was my choice, but before the purchase I sent my inquiry via email; Jens always helps. This set up only accepts 8mm motor shaft, also I bought SK8 149kv, low kv it is a must for 8/40…Only if you find a bigger motor you might have a chance to increase speed and/or keep high torque. I like HobbyKing motors, they are solid and cheap; but I might buy in the future 6384 or 6380 from TorqueBoards (they come with 8mm shaft) …Hope it helps…

1 Like