[RIPPERTON]

https://www.youtube.com/watch?v=DJMc3qF4FWM
Back on the engineering trail, using the LiPo packs that will also go into the KTM enduro bike and an old water cooled Motenergy ME0913 in an Arrow AX5 that I got from a good friend for free. Was able to reposition the seat and steering wheel centrally in the frame.
Am fitting front discs that I also got for free. They are non ventilated quad bike discs and calipers. The hydraulic system will have a transducer that will operate the regen for the rear wheels.

 

[Karter2]

Do you have somewhere in mind to run when its built?
Most local tracks wont let anything unusual on the track since public libility was enforced on them.
But if you have a private road or old airstrip ..neat !
Also brakes dont get much of a workout on regular karts/tracks so i wouldnt hope to get much back from regen.

 

[RIPPERTON]

Do you have somewhere in mind to run when its built?
Most local tracks wont let anything unusual on the track since public libility was enforced on them.
But if you have a private road or old airstrip ..neat !
Also brakes dont get much of a workout on regular karts/tracks so i wouldnt hope to get much back from regen.

We have an EV festival here once a year where odd things get demo'd on a kart track.
I could get inventive finding other places to drive it.
Dont get much regen on a race track I know but its the same as with the race bike ie you dont have the weight of the disc and caliper. Id rather have front brakes as they are always on the ground.

 

[RIPPERTON]

Front disc brakes go on. Started with extra large hubs and shortened them a bit to put the inner bearing under the disc. Welded a flange on for the disc.
The caliper mount brackets have been laser cut from 4mm mild steel.

 

[RIPPERTON]

E Stop and throttle go in.
This is the same Ford Falcon throttle pot I used for the regen on the race bike back in 2011.
Il have to change the master cylinder so I have a banjo bolt at the start of the system and a built in micro switch to activate the regen.

 

[blondebikes]

is there a particular reason why your using the regen circuit only on the brakes? and not a mico switch pot box on the accelerator?

 

[RIPPERTON]

Are you talking about throttle off regen ? Kelly doesnt need a micro switch for that, I can config it in so I have X amount of regen at zero throttle, engine brake so to speak.
But to answer your question, I like to coast on throttle off.

 

[blondebikes]

Yeah, that does answer. It never come into my planning while building the kart.

I'm almost all on or all off and hard on the brakes. Haven't found a track where coasting is used.

 

[kennybobby]

We have an electric raceway over here called Veloce that runs 48V italian karts where laptime is the deciding factor to win. We have had some special events where it was wheel-to-wheel racing, but that ended up like bumper cars at the carneval.

i started off using the full on or full off/brakes-on technique, but soon found my laptimes were not up with the top racers, so i changed to using no-brakes. The karts just don't have enough torque to accelerate and make up speed after a braking or regen move.

They are a blast to race but it is surprising how beat up you feel after 10 laps wide-open in a kart with no suspension.

 

[blondebikes]

Yeah it definitely takes it out of you.
I'll get this new kart of mine running and wire up both for comparrasons.
See if I like the coast function.

 

[RIPPERTON]

Slowly moving forward, I took a few weeks to figure the exact structure of the battery trays. Using 30x3 equal angle I simply branched out from the side of the chassis without any real triangulation other than the web of the angle.
The end pieces are tangent to the top of the frame tube and the central pieces are out from the center of the tube.

 

[RIPPERTON]

https://www.youtube.com/watch?v=q4GWUNPu1VI
Got the first pack in and took it for a hoon around the block.
Quite impressive on 85v and a 200A Kelly ctlr.
Straight away faster than a rental kart but with one 17kg pack on the left side of it, the steering is scary. It rails right handers nicely but pushes straight ahead in left handers. Once I get the other pack into it the steering will work properly again but with twice the power (175v 200A 28kW)it will have other kinds of steering problems.
The hybrid disc-regen brakes are phenomenal, like hitting brick wall.
You can hear the pads grinding away at the discs and the motor is moaning under regen.

 

[blondebikes]

Done well.
What speed do you think your getting up to? 70-80klm/h?

Enough torque to break traction?

 

[Karter2]

The way kart handling works by " weight jacking" to lift the inside rear wheel in corners, you may have to stiffen the chassis to compensate for the extra weight out on those panniers.
But there should be adjusters for king pin inclination , that will also help.

 

[blondebikes]

Mine will be a little different with the intrepid chassis. I've put my D&D over axle. And batteries where the 2stroke would be. With only 9kg of battery key weight will be to have enough torque to break traction.

 

[RIPPERTON]

The way kart handling works by " weight jacking" to lift the inside rear wheel in corners, you may have to stiffen the chassis to compensate for the extra weight out on those panniers.
But there should be adjusters for king pin inclination , that will also help.

Jacking is necessary only because of the single piece axle and single motor.
With electric drives we can easily go to twin motors and split the axle then remove the rearward tilt of the steering axis leaving only the inward tilt for self centering effect.
Then we have a 4 wheeled kart ie one that has its inside rear wheel firmly on the ground delivering traction like its supposed to.
Would not want to stiffen the chassis as a bendy chassis is the only thing a kart has for suspension. The ability for the chassis to twist keeps all 4 wheels on the undulation ground.
Im currently devising a way to right the steering C brackets so they are perfectly upright. Theres a lot of cutting and welding going on down here.

 

[Karter2]

Sure, if you planning on splitting the axle and running 2 motors ?
If not, you will experience some impressive understeer.
It wont matter if you are not worried about ultimate performance, but i can assure you it will handle poorly.

...... but with one 17kg pack on the left side of it, the steering is scary. It rails right handers nicely but pushes straight ahead in left handers. I

....that alone should give you a heads up as to what to expect.
The reason it pushes (understeers) in left handers, is because it cannot "jack" the weight off the left rear due to the extra pack weight out on that side pannier.
Vice versa on the RH corners where the pack weight is increasing the jacking effect.
Running both packs will improve the LH corners somewhat, but it will not be a balanced handling set up.
Ideally, any exta weight should be centrally located to minimise its effect on handling.
Remember , chassis flex depends largely on the all up weight it is carrying.
I was simply suggesting you may have to stiffen the chassis to compensate for the extra weight those batteries out on the panniers.
There are many kart classes that run twin motors, high power motors (100+ hp), and they all manage quite successfully with a solid axle and "weight jacking" to compensate, and chassis set up to suit the weight and power.
The "art" in kart set up is a fine balance between chassis stiffness (adjustable) , king pin inclination,(adjustable), front and rear track width adjustments ( adjustable) etc etc
Even seat position and location points are changed to suit track conditions.
OR.... Maybe this would be simpler.... http://www.peerlessgear.com/node5380.aspx?nid=300843
.

 

[Functional Artist]

https://www.youtube.com/watch?v=q4GWUNPu1VI
Got the first pack in and took it for a hoon around the block.
Quite impressive on 85v and a 200A Kelly ctlr.
Straight away faster than a rental kart but with one 17kg pack on the left side of it, the steering is scary. It rails right handers nicely but pushes straight ahead in left handers. Once I get the other pack into it the steering will work properly again but with twice the power (175v 200A 28kW)it will have other kinds of steering problems.
The hybrid disc-regen brakes are phenomenal, like hitting brick wall.
You can hear the pads grinding away at the discs and the motor is moaning under regen.

Hello Ripperton,

Nice kart & EV-mods

Could you share your motor & controller wiring diagram?

Specifically, on this set up, are you using
...a standard contactor, a reversing contactor or just the E-stop switch?

 

[RIPPERTON]

Hello Ripperton,
Nice kart & EV-mods
Could you share your motor & controller wiring diagram?
Specifically, on this set up, are you using
...a standard contactor, a reversing contactor or just the E-stop switch?

Its as simple as I can make it. Theres just one manual E Stop button for the main battery cables.
Theres a 12v battery under the steering wheel which will later be replaced with a DCDC once the battery pack goes to 175v.
Theres an on/off switch and reverse button on the sides of the dash.
Would like to add a volt meter so I have a vague idea of when the battery is flat.

 

[Functional Artist]

Its as simple as I can make it. Theres just one manual E Stop button for the main battery cables.
Theres a 12v battery under the steering wheel which will later be replaced with a DCDC once the battery pack goes to 175v.
Theres an on/off switch and reverse button on the sides of the dash.
Would like to add a volt meter so I have a vague idea of when the battery is flat.

OK, so the 12V battery powers the controller (switched by the on/off switch)
How does the reverse button operate? (do you use reverse much?)

Are you running IIRR 85V thru just the E-Stop button?

I have used a small Amp/Volt meter, usually to monitor the amp draw when testing different motors
...or like this "Turbo" overvolting test

https://www.youtube.com/watch?v=H-704ZyJkaU

...it seems to give decent voltage readings too