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Posted: Mon Dec 08, 2008 7:16 pm
by richard
Sorry if this is a repeat post as i am new to this forum and only up to now used to playing with petrol cars.
I have access to an old electric ( 80 volt ) 3 Ton Forklift and charger and am interested in using at least the contol gear to do a DIY conversion of any 4 seater car to get me to and from work.Batteries are shot.
Work is 5 miles away mainly flat 30 mph max and i can charge at home and hopefully at work, but would rather be able to do about 20 miles round trip.
Do you think this is good cheap base ?
I also want to know if the motor which i assume is a large dc unit will be any good to me.
One thing i cannot understand is on a couple of articles i have read, it suggests that the ideal rpm i should look for in a motor for a conversion is between 300 and 400rpm.
If the motor is bolted directly to the gearbox of a car how can it achieve normal road speed as to get to 30 mph i have to do about 2000 rev in present car.
Would I be able to use the control gear and a another suitable motor?
Any advise woud be welcome,please keep it simple ( like me ).

Posted: Mon Dec 08, 2008 8:12 pm
by Jeremy
Not really my field of expertise, but I think you stand a good chance of being to re-use quite a bit out of the forklift.

The chances are that the motor will be fine, as may be the controller, contactor etc.

Your performance expectations seem reasonable, and in all probability you won't need the gearbox, as you are only looking for a modest speed range.

I'd go for the lightest donor car you can find that still has room for enough batteries. For low speeds, aerodynamics are of less importance than weight, as weight directly affects rolling resistance and the power needed for acceleration.


Posted: Mon Dec 08, 2008 9:40 pm
by geekygrilli
Hi Richard

I am pretty sure you will be able to use the existing controller in the forklift, and I would put effort in getting that working, as the controllers are the expensive bit! If you use your existing motor and controller you will know for sure that they are compatible.

I used a forklift motor in my conversion; rated at 47v, but I am running it at 96v. It revs to 3500rpm, so I sit in 2nd or 3rd gear.

What does the forklift motor have written on it with regards to rpm? If you leave the gearbox in the car and just attach the motor to the i/p shaft you should be OK, as you can just select a gear to match the characteristics of your motor.

5 mile commute is easily do-able, mine does 25 miles max, running on 110Ah Leisure batteries.

There is a good website of some chaps in A-merica who converted a Swift using 48v forklift as a donor

Where abouts are you?



Posted: Tue Dec 09, 2008 2:52 pm
by ForkenSwift
Canadians, ahem. :wink:

Posted: Tue Dec 09, 2008 2:59 pm
by ForkenSwift
Two others (Americans) that I know of have since built EVs using forklift motors & some of their components.

See: It’s a Trend! 3 Dirt Cheap DIY Electric Cars

In ours, we re-used from the forklift:

- one of its four DC motors
- pot box
- cabling
- contactors
- main fuse

We didn't use the forklift controller though, because it was an older SCR type, and the newer PWM mosfet style ones are more efficient. Ours is from a golf cart.


Posted: Tue Dec 09, 2008 6:37 pm
by geekygrilli
Hi Darin

I am so sorry for falsly accusing you of being American! Please accept my humble apology!

I would also like to say that you were part of the inspiration for my conversion, and I followed your blog/vids closely (though not close enough to notice what country you live in!) My car is on

Its good to see people recycling old forklift parts, I have a spare motor, contactors and loads of cabling sitting in my garage ready for the next car.

Welcome to our forum!

Best regards


Posted: Tue Dec 09, 2008 10:14 pm
by ForkenSwift
Christopher -

Apology accepted :D

That's a nice job you've done. Much better workmanship than the ForkenSwift!

I've recently thought it would be fun to make a "family tree" of conversions that show where people got their inspiration. I expect it might reveal some interesting patterns.

Thanks for the welcome to the forum, but I must admit I likely won't hang around (too many forums, not enough time!!). I happened by because the link from here to showed up in my logs.