TB Vesc 4.12 (Bought May 10 2018) - Mosfets almost over heat

Hey everyone!

So my mosfet temperature seems wayyyyy too high. From my understanding most people is somewhere around MAX 40 degrees celsius when riding hard. My temperature reaches anywhere from 70-85 degrees celsius. This also causes the board to go from a max speed of 50 km/h to 20-30 km/h (the point where I almost get passed by bicycles :joy:) which luckily saves my vesc from not being toasted.

So after looking around on the forum, it seemed like a few other people had experienced somewhat the same as me with the same vesc bought around the same time. The reason was because of a bad batch. I’m thinking it’s the same for me since my settings are not too crazy.

The vesc was bought on the 10 of May 2018 and have been used for around 125 km in total, so shouldn’t be caused by wear.

There is no hills around me, but I usually like to accelerate as hard as possible

Does anyone have any suggestions? @torqueboards

As usual, any input is appreciated and thanks for reading all the way to the end.

Vesc settings:

Video is a bit old, but just realized I had the same issue back then, just never effected speed…


Max temperature can be seen upper left for the temperature box in the right top corner.

↓↓↓↓ Temperature reached just above cut-off start and got this error code. I got it when I accelerated as hard as possible. It made the board brake…

I wouldn’t expect something else on a hw 4.12 vesc without extra attached heat sink. I can’t speak out of personal experience but I read that multiple people have over hearing issues when setting bat max to 30-35 A or above. That was reported from different producer. Tb, Flipsky 4.12, hobbyking etc.

Will try to set it lower :slight_smile: Thanks

Then time to look for an old school focbox :money_mouth_face:

What kind of wheels are you using? If they have high rolling resistance that could be your culprit.

@Mobutusan Both on 90mm and 97mm wheels I get high temperatures. The temperature is a bit higher with 97mm though. Gearing is 16/36

1 Like

Changed my settings to:

  • Motor max: 65A
  • Motor min: -65A
  • Batt max: 27A
  • Batt min: -8A
  • Max wattage: 1300W

I still got really high temperatures.

Even when riding 23 km/h with 20A for motor and 10A battery the temperature was still at 80 degrees celcius the whole time??? Wtf


Also got the same error code as before when I reached max temperature which could have thrown me off (almost did)


Here is the whole ride: image