7 ms·

Thanks for sharing, is that engine sound coming from the truck?

by ludamn 10mo ago

analog31 10mo ago
Sounds like the person taking the video is on an electric bike.
- pabs3 10mo ago
  I think its the truck, near the end the bike peels off to the left and you can hear the sound fading off to the right.
- thenthenthen 10mo ago
  Op here, the sound is the truck, it sounds like a toy really haha.
ehnto 10mo ago
It's from the truck, it's the transmission of the truck which is evident by changing pitch as the truck downshifts while slowing down. It likely uses a transmission as a tradeoff between torque and RPM of the electric motor or because it's a simpler task to retrofit an existing truck driveline with an electric motor bolted onto it. These are so noisy because of the use of straight cut gears, which you choose when preferring strength over noise and comfort. Most regular cars use helical gears which reduces the noise due to continuously meshing between gear teeth, whereas straight cut gears are like a paddle wheel, so the teeth are smacking into eachother head on each time they engage. That is also why they clunk when getting on and off throttle. We have some similar trucks running around Australia at the moment and the sound is the same, I'm also familiar with the sound from motorsport!
- swiftcoder 10mo ago
  Are there weight/performance reasons why an electric truck would need a multi-speed transmission? Most electric cars only have a single-speed
  - lan321 10mo ago
    Some cars have 2 gears as well. One for the acceleration and one for cruising efficiency and top speed. So my guess is to get it going easier and then have 2nd as the eco gear for the speed they cruise at.
  - ehnto 10mo ago
    I am unsure sorry, electric motors do still have efficiency curves so that could be it. But I think a retrofit to an existing driveline makes more sense. Food for thought though, trucks are much much heavier loaded than cars. 100-150+ tonne vs like 1.5-4 tonnes for a car. Cars are trivial by comparison. Perhaps the motor they have available doesn't have enough torque for it without gearing down.
    - swiftcoder 10mo ago
      > Perhaps the motor they have available doesn't have enough torque for it without gearing down. This is true of cars too - the single-speed transmission in a Tesla is a 9:1 reduction gear, for example.

Thanks for sharing, is that engine sound coming from the truck?

by ludamn 10mo ago

Thanks for sharing, is that engine sound coming from the truck?

analog31 10mo ago

Sounds like the person taking the video is on an electric bike.

pabs3 10mo ago
I think its the truck, near the end the bike peels off to the left and you can hear the sound fading off to the right.
thenthenthen 10mo ago
Op here, the sound is the truck, it sounds like a toy really haha.

ehnto 10mo ago

It's from the truck, it's the transmission of the truck which is evident by changing pitch as the truck downshifts while slowing down. It likely uses a transmission as a tradeoff between torque and RPM of the electric motor or because it's a simpler task to retrofit an existing truck driveline with an electric motor bolted onto it. These are so noisy because of the use of straight cut gears, which you choose when preferring strength over noise and comfort. Most regular cars use helical gears which reduces the noise due to continuously meshing between gear teeth, whereas straight cut gears are like a paddle wheel, so the teeth are smacking into eachother head on each time they engage. That is also why they clunk when getting on and off throttle. We have some similar trucks running around Australia at the moment and the sound is the same, I'm also familiar with the sound from motorsport!

swiftcoder 10mo ago
Are there weight/performance reasons why an electric truck would need a multi-speed transmission? Most electric cars only have a single-speed
- lan321 10mo ago
  Some cars have 2 gears as well. One for the acceleration and one for cruising efficiency and top speed. So my guess is to get it going easier and then have 2nd as the eco gear for the speed they cruise at.
- ehnto 10mo ago
  I am unsure sorry, electric motors do still have efficiency curves so that could be it. But I think a retrofit to an existing driveline makes more sense. Food for thought though, trucks are much much heavier loaded than cars. 100-150+ tonne vs like 1.5-4 tonnes for a car. Cars are trivial by comparison. Perhaps the motor they have available doesn't have enough torque for it without gearing down.
  - swiftcoder 10mo ago
    > Perhaps the motor they have available doesn't have enough torque for it without gearing down. This is true of cars too - the single-speed transmission in a Tesla is a 9:1 reduction gear, for example.