[rickyd123]

I'm new and very green. I was looking at forklift motors on ebay. It looked like most all of them only went to a max of 48 volts. That isn't enough for a car. Right? The motors listed on this site are 144volts. So if I want to be able to go 40 mph in say a ford probe. A fork lift motor isn't going to cut it. Right?

[DJBecker]

Originally Posted by rickyd123

I'm new and very green. I was looking at forklift motors on ebay. It looked like most all of them only went to a max of 48 volts. That isn't enough for a car. Right? The motors listed on this site are 144volts. So if I want to be able to go 40 mph in say a ford probe. A fork lift motor isn't going to cut it. Right?

The motors can usually withstand much higher voltages, but not handle the power from higher voltage if at 100% duty cycle. Their limits are the current through the brushes, cooling the brush assembly, the maximum RPM and long term heating. Roughly in that order.

[Duncan]

Hi Ricky
DC motors are old technology - been the same for a number of years

put a DC EV motor next to a forklift motor and look for the differences - look hard!

Not much to see

The main difference is the duty cycle - a fork lift motor is specified for continuous (one hour) operation - and has a good safety margin such that 20 years life is not unusual

The sizes of motors we use are fitted to forklifts that weigh ~4 tonnes - more

A home built EV cannot use power continually - not enough battery life
So it can be overrated for a short period

[rickyd123]

So Duncan. Am I understanding you right? Forklift motors are well built so they can handle more juice and forklifts are a lot heavier then small cars. Those two things make them very suitable to be used to make a practicable EV. I'm going to need this vehicle to go 40mph for 45 min. Do you think that is achievable with a forklift motor.

[DIYguy]

Originally Posted by rickyd123

I'm new and very green. I was looking at forklift motors on ebay. It looked like most all of them only went to a max of 48 volts. That isn't enough for a car. Right? The motors listed on this site are 144volts. So if I want to be able to go 40 mph in say a ford probe. A fork lift motor isn't going to cut it. Right?

Many forklift motors are good for EV conversions. Some are better than others. Some not so good, like a pump motor with internal drive end and intermittent rating.
In order for a good doner lift motor that was originally rated for 36/48 volts to be used at 144, the brush timing needs to be advanced to mitigate the arcing that would occur at higher rpm/voltage. The continuous rating does not change however, the intermittent power requirements in an EV can still fall within acceptable limits.
I have a 9" GE lift motor in my Mazda (Ranger) pick up. It was originally rated for 36/48 volts. It works fine and has more power than the original 4 litre 6 cylinder. I limit the voltage to the motor at 170 volts and can drive hiway speeds without a problem. Supplementary cooling (blower) can aid in keeping it cool and improving on the original continuous HP rating also.