Electric Shifter Go-Kart

[Kai]

Hi my name is Kai, and I plan on building an Electric Shifter Go-Kart with a Handbrake, Bucket seat, Light Bar on the Front, Along with a full Light Kit, Indicators, Reversing lights, ECT you get the point, And somehow adding two Mirrors so I can see behind me, Also a nice Five-point safety Harness, A Speedometer, A Killswitch for EVERYTHING, then two more switches, 1. Turn it to activate power then turn key to start, 2. being Lights. Also, a detachable Steering Wheel to be sure no one can drive off. I have a budget of $1.5K to build it all I hope for it to go 100MPH max, Wide tires on the back, Just a clean dream speeding machine.

 

[Whitetrashrocker]

Awesome! I can't wait to see it.
Post pics!

 

[Functional Artist]

Hi my name is Kai, and I plan on building an Electric Shifter Go-Kart with a Handbrake, Bucket seat, Light Bar on the Front, Along with a full Light Kit, Indicators, Reversing lights, ECT you get the point, And somehow adding two Mirrors so I can see behind me, Also a nice Five-point safety Harness, A Speedometer, A Killswitch for EVERYTHING, then two more switches, 1. Turn it to activate power then turn key to start, 2. being Lights. Also, a detachable Steering Wheel to be sure no one can drive off. I have a budget of $1.5K to build it all I hope for it to go 100MPH max, Wide tires on the back, Just a clean dream speeding machine.

To go 100MPH,
...just the propulsion system (motor & speed controller) are going to cost you in the ~$1.5K
...then, the battery pack to power it will be, probably be just as much

That's ~$3K before you get to lights, switches & mirrors

Plus, 100MPH on a go kart?

IMHO
It better be a bad azz
...designed, engineered & built go kart

 

[Kai]

To go 100MPH,
...just the propulsion system (motor & speed controller) are going to cost you in the ~$1.5K
...then, the battery pack to power it will be, probably be just as much

That's ~$3K before you get lights, switches & mirrors

Plus, 100MPH on a go-kart?

IMHO
It better be a bad azz
...designed, engineered & built go kart

I've been looking and, I'm getting
Two 48V 2000W DC Motors $224
Two 48V 2000W Motor Controllers $184
3 pole battery input charger port $12
Key Switch $3
Twelve, 12V - 7.5Ah | Rechargeable batteries $168
Any Racing Chassis I can find Locally $100-150
Steering Wheel Quick Release Kit $21
MOTACORSA STAGE DISHED STEERING WHEEL (Black Spokes) $112

-
More soon but still looking.

 

[anickode]

4000 watts of motor is only about 5.5 hp. If you go by the old "1hp electric is the same as 2hp gas" saying, you're still only at 11hp gas equivalent.

4000 watts is an awful lot to pull off your proposed battery arrangement. 4 series by 3 parallel would still be a 30+ amp drain on each battery. That kind of drain will ruin them fairly quickly, and will likely only give you 10-12 minutes of run time, optimistically, since the ah capacity curve of a battery drops off as drain goes up. At 1 amp, it might be a 7.5ah battery, but at 30 amps, it might only be good for 5 or less.

Plus at 30 amps, the voltage will probably sag far below 12v per battery, even at a full charge. Could be as low as 8 volts or less depending on the brand and quality of the battery.

And batteries are heavy. Even with those small batteries, you're looking at an additional 70 lbs just in batteries.

For what you're looking to do, LiPo packs might be the only chance.

 

[mckutzy]

What's shifting on this electric kart???

If a transmission is present.... That's going to be some money right there...

 

[itsid]

BS!
4kW are not nearly enough to reach even 60mph much less 100..

but alright alright, i don't say much..

just allow me this to say:
How about you do some math first?

'sid

 

[Kai]

BS!
4kW are not nearly enough to reach even 60mph much less 100..

but alright alright, i don't say much..

just allow me this to say:
How about you do some math first?

'sid

How much kW do you think I should have to go 80mph max.

 

[anickode]

How much kW do you think I should have to go 80mph max.

Probably double... 8kw might get you to 80, but the batteries will be heavier, so maybe not.

 

[Kai]

Probably double... 8kw might get you to 80, but the batteries will be heavier, so maybe not.

All I want to do is go 80 and be light, I've got a $1k - 1.5k Price for it all.
I can't seem to find any motors that are 4kw or 5kw

 

[anickode]

All I want to do is go 80 and be light, I've got a $1k - 1.5k Price for it all.
I can't seem to find any motors that are 4kw or 5kw

Hence why functional artist said you will spend $1500 just on the drive system.

Light and lead acid batteries don't go together.

 

[itsid]

How much kW do you think I should have to go 80mph max.

Probably double... 8kw might get you to 80, but the batteries will be heavier, so maybe not.

Nope not 8kw either... (you need at least around 9kW to get to 60mph)
and it get's worse the faster you want to go (thanks to a cubed speed factor)

All I want to do is go 80 and be light, I've got a $1k - 1.5k Price for it all.
I can't seem to find any motors that are 4kw or 5kw

Do the math.. it's not difficult at all (tedious, yes; difficult, not at all!)
here's the step by step explanation to follow along
And get familiar with real world values, that makes things sooo much easier

If I had to make a guess.. we talk about 25kW here for 80 and something like 45-50kW for 100mph
and that's for the lightest possible go kart
(no more weight than your butt and a helmet really)

'sid

 

[anickode]

Bosch's electric kart has a 20kw motor and a massive lithium ion battery pack and it tops out at 80 mph.

So itsid's numbers are a little high, and my guess was way low. And they use Lithium batteries. Not lead. So you probably WOULD need 25+kw to hit 80 with wet cell batteries.

https://www.google.com/amp/s/www.cnet.com/google-amp/news/bosch-new-electric-racing-kart-prototype/

A quick Google search yielded many 20kw 48-72v brushless dc motors, all in the $1000-1500 range. Oh and they were all water cooled, so that'll add some heft to the system.

 

[itsid]

from what I've read they are TWO nominal 10kW motors peaking at ~14kW for a few seconds until they burn out. that makes it a total system power of max 28kW ...
but IDK.. I was estimating by some brutally simplified numbers..

36m/s for 80mph and 45m/s for 100mph
then just the cube of those, divided by two plus 25 times whatever speed we talk about..
makes 24.2kW for 80mph and 46.7kW for 100mph

the rest was additionally rounded to get some nice mod5 numbers

I'm too lazy to do the exact math... which in fact is pointless when we ned to estimate the weight and worse the coefficient for wind resistance;

In any case this endeavour is not at all possible with any single digit kW motors not even if they come in pairs

'sid

 

[Kai]

So how fast could I go for a total of $2k

 

[itsid]

that's a few hours of skydiving.. sooo freefall terminal velocity (roundabout'isch 230km/h maybe)
it's also a few laps on the Nürnburgring with the RingTaxi (could peak way higher... say 300km/h)

*whistle*

Kai, really.. the kind of questions you are asking
let's me think of a pubertarian that's only asking about how to impress his friends...
Asking for the most dangerous speed, making sure everyone here get's a very good idea about your lack of experience and maturity in that regard.

So yeah.. NOPE!
Sorry, I'm not going to tell you how to die quicker than your classmates.

Maybe someone else is willing to point you in some viable direction,
I'm rather not until I have at least some confidence in your maturity.

'sid

 

[Kai]

that's a few hours of skydiving.. sooo freefall terminal velocity (roundabout'isch 230km/h maybe)
it's also a few laps on the Nürnburgring with the RingTaxi (could peak way higher... say 300km/h)

*whistle*

Kai, really.. the kind of questions you are asking
let's me think of a pubertarian that's only asking about how to impress his friends...
Asking for the most dangerous speed, making sure everyone here get's a very good idea about your lack of experience and maturity in that regard.

So yeah.. NOPE!
Sorry, I'm not going to tell you how to die quicker than your classmates.

Maybe someone else is willing to point you in some viable direction,
I'm rather not until I have at least some confidence in your maturity.

'sid

I'm not trying to impress anyone I don't need to, Plus I don't care what people think that's why I don't bother with impressing anyone.
Plus being in a go-kart is the only thing that lets me think straight. I feel happy in a go-kart.
Plus It's not like I'm suicidal if I was I'd just buy a 600cc engine and a prebuilt go-kart with my money and pay someone to get it working for me. Then go speed. No I just want to have fun at a moderate speed of 50-60

 

[anickode]

My question is why are you so hellbent on electric? Think about electric cars... If they were cheap and practical we would all drive them, but until recent battery technology advances, electric cars have been for the most part, heavy, slow, and expensive. The battery tech is still expensive. The only EVs on the market that will match or outperform regular cars cost 2-5x as much, use massively powerful liquid cooled AC motors with inverter drives, and gigantic liquid cooled lithium ion battery packs. And they outweigh their ICE counterparts by a fair margin.

I'm not trying to start the gas vs. electric debate here, but as far as max performance for the money goes, it's still all about gasoline.

$500 will buy you a 200cc Lifan bike engine that will get you darn close to 80mph bone stock.

What is your motivation here? A bet? Bragging rights? Or just a randomly thought up set of specs that sound cool?

 

[Kai]

My question is why are you so hellbent on electric? Think about electric cars... If they were cheap and practical we would all drive them, but until recent battery technology advances, electric cars have been for the most part, heavy, slow, and expensive. The battery tech is still expensive. The only EVs on the market that will match or outperform regular cars cost 2-5x as much, use massively powerful liquid cooled AC motors with inverter drives, and gigantic liquid cooled lithium ion battery packs. And they outweigh their ICE counterparts by a fair margin.

I'm not trying to start the gas vs. electric debate here, but as far as max performance for the money goes, it's still all about gasoline.

$500 will buy you a 200cc Lifan bike engine that will get you darn close to 80mph bone stock.

What is your motivation here? A bet? Bragging rights? Or just a randomly thought up set of specs that sound cool?

I have a solar system well my neighbors do but they let me use it a lot, And I'm planning on buying one too. Then I can charge batteries and I'd rather be using electric than gas because for me It's cheaper.

 

[anickode]

I'm not trying to impress anyone I don't need to, Plus I don't care what people think that's why I don't bother with impressing anyone.
Plus being in a go-kart is the only thing that lets me think straight. I feel happy in a go-kart.
Plus It's not like I'm suicidal if I was I'd just buy a 600cc engine and a prebuilt go-kart with my money and pay someone to get it working for me. Then go speed. No I just want to have fun at a moderate speed of 50-60

Ok, first it was "has to go 100"
Then it was "at least 80"
50mph is more doable. Still a huge undertaking, but doable.

100mph is near suicidal on a go kart no mater what's turning the wheels, so your bike engine argument doesn't make much sense.