Optimal motor KV for offroad and top speed?

I use 2x 6374 turningy 149kv motors on my trampa build. I’m in love with the torque it provides and the hill climbing abillity. However my top speed is at 38 kph with a gear ratio of 6:1.

I want to be able to reach around 60 kph just for the heck of it (i need to lower gear ratio and get other motors). How much offroad capabillity would i have to sacrifice if i switch to 190kv motors instead? I see alot of people running 190kv motors on their trampa boards. I’m not sure if they use their board primarily in urban areas.

Basicly, i want higher top speed but i still want to be able to shred mountainbike tracks in the forest, would 6374 4400w 190kv motors and a gear ratio of 4:1 work fine in heavy offroad conditions and for hill climbing?

Thanks in advance!

Do not change the motors yet, change the gear ratio, easiest way is to change the motor pulley first.

How many teeth you have on motor and wheel?

190kv + 4:1 is too much, I tested it and it has no torque and brakes are too weak, final speed is way too much a Trampa

Ohh really? Is it too weak for offroad or does the urban driving also become limited? I feel that a trampa board should be able to handle higher speeds than a normal longboard setup? It feels more stable.

I have the torqueboards motor mount and pulley kit, it is 72t 12t. It was the only option that TB offered. Ive already ordered 66t and 15t sets from trampa, this will get me to 47 kph. I also ordered 18t motor pulleys but im not sure if that one will work since the diameter might be to large.

I’ve already ordered 2x pulley kits from trampa

60 kh on a flexible deck is not a good idea imho. I’d upgrade motors size, not kv.

Oh okay, speed concerns are because of the flex. Didnt think of that tbh. Its not like i will be going at 60 kph frequently, more like i want to be able to do it :sweat_smile:

I think @Kug3lis uses big motors. I don’t know how fast they are nor the ratio he is using

6374 motors seems to be more than enough though. I know my gear ratio is high and i use 150 kv motors but from a standstill on steep hills i easily reach top speed in like 5 seconds. That’s why im curious if a 190kv setup would work almost as good on hills and off-road. Right now i feel like the board could climb a wall, it has way more torque than necessary :sweat_smile:

I use 190 on my off-road trampa build and have plenty of power and can hit 32mph.

What gear ratio do you use? 5:1? Have you tried hitting heavy off-road tracks like mountainbike tracks?

you can go 38kmh & want to go 60kmh…


6 gear ratio / 1.5789 = 3.8:1 gear ratio

1 / 1.5789 = 0.633

^you need a 3.8:1 gear ratio for ~60kmh and you’ll have about 63.33% as much acceleration as you have now after changing the gearing (~36.7% loss of thrust/acceleration)

you can recover the loss of acceleration from the gearing change by increasing your present motor current limit x 1.57

since heating increases at the square of current your motors and controllers will heat 1.57^2=2.46x faster as they did before for the same acceleration.


5:1 I ride on dirt hiking trails and at times I will do a burn-out on 80 motor amps. Yet to find a hill I can’t do

Cool man, thanks for the info! :slight_smile: as you have experience of a trampa going at 32 mph (roughly 52 kph) would you say that the board handles the speed well? Do you consider higher top speed to be dangerous?

Nice to see some math! Hmm well that much loss in torque is not worth it i guess. How about using 190kv motors? My current motors are 149 kv 3500 watts (80a max). Would motors rated with 192 kv 4400 watts (100a) max automaticly mean less torque? Since they are rated for more watts that should eliminate some differences?

You’ll experience the same loss of acceleration if you change the KV as if you change the gearing…

Okay, i see. But shouldnt 4400 watts provide more torque than 3500 watts? If the motots was the same kv that is

50km/h is the mark for me when it gets more hard to don’t fall into speed wobbles. If you have a confident stand and the right dampas 55-60 shouldn’t be an issue on good roads. Which ply deck you have and how heavy you are?

@JensSjogren see what i added to my original post:

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I got 16 ply and red (stiff dampas). I weigh 88 kg.

You speak about the sk8 motors? Can you explain me why the 150kV is rated only to 80a and the 190kv to 100a with the same size, same weight? 190kV is rated 4400w 150kV only 3500w

Oh shiiet, that would require some serious heatshrinks on the focboxes i guess! Maybe better off to try 4:1 ratio on the 150kv motors. That should give a top speed of 51 kph. Lets just start there :sweat_smile: