Need help with electric go kart

[Quinc]

Go with the 140cc piranaha for 400$. Then when you are board with karting you can put it in an ATC70 or z50.

Or pick up a roached out chinese pocket bike with a 125cc engine off CL for 100$

If you buy used and the seller uses the phrase: "Just needs the carb cleaned" It means the seller has no idea what is wrong with it and it could possibly need a new top end and crank. So make sure you do a compression test on any used engine you buy and check for spark.

---------- Post added at 08:43 AM ---------- Previous post was at 08:29 AM ----------

and later when I have more money convert it to electric

Did you not see my post about how to build a cheap electric kart? Also unless you are riding the **** out of the thing daily those Chinese motors will easily handle a few extra volts/rpms. I have pushed the 500w 36v to 60v without issue. Just make sure your gearing is low so the motor is not working too hard.

Here is a guy running 2x unite 48v 1000w motors at 60v 5ah lithium batteries and getting 15m of run time.
https://www.youtube.com/watch?v=P9b6UdxyRHM

 

[itsid]

I really hate such comments..
overvolting is the stupidest thing in the world.. most motors will just fry and the few that survive,
are NOT delivering any significant extra power (just very significant extra HEAT!)



'sid

 

[Quinc]

I really hate such comments..
overvolting is the stupidest thing in the world.. most motors will just fry and the few that survive,
are NOT delivering any significant extra power (just very significant extra HEAT!)



'sid

More volts = more rpms/speed. Heat can be managed through gearing. While I understand on paper it looks bad. Myself and countless others have never had an issue.

The video I posted of the guy over volting and running significantly more amps to those motors is still going strong 3 years later.

 

[TBNRGoKart]

Ok, but the minimoto is for 10yr olds...im 14 and i wanted it to drive around where i live its a gated community and it needs to go at least 30 mph and i wanted a semi auto engine so i would look cool when i drive it and also...

What parts do you need to build a rolling chassis

<img src="https://d2j6tswx2otu6e.cloudfront.net/aOiXrsxiYlN76vxC6g_A22CiHDs=/600x337/b71a/b71a94fadc6f4bc18448e28da219655a.jpg" alt="Image result for shopping cart go kart"/>

I wanted to guild one like this but would which would be easier to build?

<img src="https://i.pinimg.com/originals/07/5a/d1/075ad11992d25279d78121ec89e6bf73.jpg" alt="Related image"/>

 

[Quinc]

Ok, but the minimoto is for 10yr olds...im 14 and i wanted it to drive around where i live its a gated community and it needs to go at least 30 mph and i wanted a semi auto engine so i would look cool when i drive it and also...

I am 6' 240lbs in that video and fit "ok". If I was going to continue riding it I would cut the frame in half stretch it and add a real gokart seat to it.

I would say the shopping cart will be most noticeable going down the street. But you cant beat the look of the race kart.

Some good info here on building frames etc on the cheap.
http://www.powerracingseries.org/

 

[itsid]

haha kiddo... ... THANK YOU! long time since I've been called that with all the grey beard and such

Anywhoo.. your post is BS!

first: only straight DC motors (2-pole) react to increase voltage with increased rpms..
brushless motors (like the one discussed earlier) DO NOT the ONLY way to increase rpm is to alter the sequence timing.

See.. and with just that your false claim is right out the door...

Anywhoo..
second: motors are wound for a specific Voltage range
And are labelled for such..
Increasing the Voltage potential ONLY increases the coils inductance,
which then splits into heat and magnetic field strength
(and with increased inductance more and more towards heat and less and less towards field strength)
heat can then reduce the magnetic field strength of nearby permanent magnets
(ferric less affected than Niodymium... both don't like to get cooked however)
Sep ex motors suffer from a similar behavious since the stator coils are also heated of course and thus reduce magnetic field strength just liek the coil itself...

Again, few can tolerate that given they're pottet and insulated with higher temperature range material.. but most are not. they'll slowly boil off insulation material and eventually short out.

Adding amps and more volts is completely impossible (again talking 'above specs' here)
simple reason.. the coils don't grow.. and if not shortened out don't shorten either...
they certainly not cool down because of such increase in load..
SOOOO the overall resistance will grow as well,
and there you have it... resistance is mostly futile but never in electric context
Thus the coil will accept less and less amps the hotter it gets.

What you are claiming there is having found a way to
a) either create a hot superconduction
b) cheated around the third law of thermodynamics.

and to that I have to say: you can't and you most certainly can't

The ONLY way that might be possible is if you cooked off most of the magnetic field strength of the permanent magnets in which case the magnetic resistance drops significantly and a higher amperage can be pushed through the coils without much of additional heat..
BUT that means the motor lost most of it's mechanical efficiency (AKA POWER!)
And while you push 20kW of electrical energy in you still get no more than the labelled 2kW of mechanical power.

So granny, stop claiming BS!

Do a sincere complete test and you will see that yourself.
get the datasheet handy and measure the mechanical ppower at your claimed volts and amps..
you'll certainly see that you gained nearly nothing (more likely lost a couple of watts by now!)

'sid

 

[TBNRGoKart]

Some good info here on building frames etc on the cheap.
http://www.powerracingseries.org/

That is something i've wanted to do for about 2 yrs now but...
im not old enough and i dont have the money to drive all the way there and stay the night in a hotel(or 2) and my parents wouldn't allow me to do that until im 16 anyways...

And about the "Shipping Kart" as my friend calls it I think im going to try and make that one and any ideas what parts i would need to make just the rolling chassis i've tried to look around but all the stuff i find it gives you a list 100,000 years long and I just want to know the simple stuff I would need to build just the rolling chassis with brakes and the website im trying to get all the parts from(if possible) is www.bmikarts.com[url]

 

[Quinc]

haha kiddo... ... THANK YOU! long time since I've been called that with all the grey beard and such

Anywhoo.. your post is BS!

first: only straight DC motors (2-pole) react to increase voltage with increased rpms..
brushless motors (like the one discussed earlier) DO NOT the ONLY way to increase rpm is to alter the sequence timing.

See.. and with just that your false claim is right out the door...

Anywhoo..
second: motors are wound for a specific Voltage range
And are labelled for such..
Increasing the Voltage potential ONLY increases the coils inductance,
which then splits into heat and magnetic field strength
(and with increased inductance more and more towards heat and less and less towards field strength)
heat can then reduce the magnetic field strength of nearby permanent magnets
(ferric less affected than Niodymium... both don't like to get cooked however)
Sep ex motors suffer from a similar behavious since the stator coils are also heated of course and thus reduce magnetic field strength just liek the coil itself...

Again, few can tolerate that given they're pottet and insulated with higher temperature range material.. but most are not. they'll slowly boil off insulation material and eventually short out.

Adding amps and more volts is completely impossible (again talking 'above specs' here)
simple reason.. the coils don't grow.. and if not shortened out don't shorten either...
they certainly not cool down because of such increase in load..
SOOOO the overall resistance will grow as well,
and there you have it... resistance is mostly futile but never in electric context
Thus the coil will accept less and less amps the hotter it gets.

What you are claiming there is having found a way to
a) either create a hot superconduction
b) cheated around the third law of thermodynamics.

and to that I have to say: you can't and you most certainly can't

The ONLY way that might be possible is if you cooked off most of the magnetic field strength of the permanent magnets in which case the magnetic resistance drops significantly and a higher amperage can be pushed through the coils without much of additional heat..
BUT that means the motor lost most of it's mechanical efficiency (AKA POWER!)
And while you push 20kW of electrical energy in you still get no more than the labelled 2kW of mechanical power.

So granny, stop claiming BS!

Do a sincere complete test and you will see that yourself.
get the datasheet handy and measure the mechanical ppower at your claimed volts and amps..
you'll certainly see that you gained nearly nothing (more likely lost a couple of watts by now!)

'sid

Yes I get the math. And thank you for the correction on the brushless.


However, I have DONE IT. And so have a ton of other people; successfully, multiple times with dozens of hours of operation.

The video I posted the guy and his kid have been driving that kart around for 3 years and the motors are still going strong.
Look at the razor kart forums where almost everyone ups there 24v 250w motors to 36v and 500w motors to from 36v to 48v+. I have read through countless threads and topics of people doing this and the only issue anyone has is when the controllers cannot handle the extra volts.


*Of course gearing has a lot to do with keeping the motors from over heating.

**Should note that I absolutely agree with you if you are looking to be as efficient as possible and keep the motor working for as many years as possible. If I was building an actual race ev kart and using an expensive motor I would stay as close to that math as possible.

 

[TBNRGoKart]

And about the "Shipping Kart" as my friend calls it I think im going to try and make that one and any ideas what parts i would need to make just the rolling chassis i've tried to look around but all the stuff i find it gives you a list 100,000 years long and I just want to know the simple stuff I would need to build just the rolling chassis with brakes and the website im trying to get all the parts from(if possible) is www.bmikarts.com[url][/QUOTE] Please if anyone can help...

 

[Quinc]

Please if anyone can help...

http://bfy.tw/IH49

 

[TBNRGoKart]

...

 

[mckutzy]

Well he helped you... whats the problem??.....

Were not going to do all the work for you.... You do need to do a ton of research by the looks of things...

 

[TBNRGoKart]

You do need to do a ton of research by the looks of things...

I've been doing around 3-4, maybe even 5 months of research on building one and 3-4 years of wanting to build one

But im definitely going for the "Shipping Kart" design

 

[landuse]

As far as I remember there were one or two shopping kart builds on the forum here. Have a look around for them

 

[TBNRGoKart]

Ok i did and found some pics but did not have any luck finding any but anyone have any recommendations for a 100-125cc engine for my go kart?

I found some on eBay but I would like a automatic one or a semi-auto but not full manual because i haven't gotten that far yet

 

[mckutzy]

Howabout just start small... A clone from HF, cent clutch... A cheap and easy way... No messin with wiring and such... Gas and go..

 

[TBNRGoKart]

Ok, I might just try a small 49cc engine for now since I have one laying around, but could you tell me if I have all the parts for building the rolling chassis?

So far I have,

1 1" Steel live axle w/ full keyway
3 Cast iron pillow blocks w/ 1" Bearing
1 Mechanical brake caliper
1 Steel multipattern brake hub (1" bore)
1 Brake rotor (6"x1/8")
1 11" Steering wheel w/ cap
2 Medium tie rod kit (16-1/2")
4 6"Unilli racing SL slicks (10.5"x4.50-6)
4 6" Split rims (3-1/2" Bolt pattern)
4 Wheel Hubs w/ (4) 3/8" bolts on a 3-1/2" Bolt circle
2 1/4"x1/4" Keystock for live axle

Building Materials

10Ft 1" Steel Square Tubing
1 Old shopping cart


Is that all the parts I would need to complete a rolling chassis?

 

[mckutzy]

I'd say another 5' of material just to be sure.
Shaft collars. 2per bearing and item on shaft...
1' of key stock.
Hardware- nuts, bolts, washers and lock washers...
Tube of blue locktite.
That's off hand...

 

[Quinc]

I'd say another 5' of material just to be sure.
Shaft collars. 2per bearing and item on shaft...
1' of key stock.
Hardware- nuts, bolts, washers and lock washers...
Tube of blue locktite.
That's off hand...

And two rattle cans of flat black.

 

[TBNRGoKart]

And two rattle cans of flat black.

Im doing a ocean blueish color

And I meant to say shaft collars (about how many?) and I have 2' of key stock