Hybrid Kart Brainstorming

JTSpeedDemon

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So after seeing a bunch of cool hybrid and twin turbo type cars at the Petersen Automotive Museum here in L.A I've latched onto the idea of turning the Green Monster into a hybrid go kart, so this'll be my thread to crowdsource and get input on my ideas and designs.
@Functional Artist I know you're pretty familiar with Boma brushless motors and the likes, I think you mentioned before how there's kits somewhere on the web for a full setup? Mind linking a few of those kits?

So yeah right now I'm thinking of running the Raptor FHB sent me on the Green Monster, but also having an electric setup as well, which'd give me low speed power, reverse, and potentially a stronger take off.
The big problem I'm thinking about at the moment is the drivetrain. I want to set up the Raptor with a 3D Motorsport manual clutch so this thing will be nice and flexible to drive, but I'm trying to figure out how to run a high power engine without overspeeding the electric motor.
I don't think I trust a sprag bearing to hold up to a 10K RPM engine and 10- 15 HP, but I want to make the electric motor geared low for low speeds. Now the problem with that is the lower it's geared, the faster it'll spin in relation to the axle, making the speed limit on the motor much lower. So I could just gear the electric motor crazy tall but that defeats the purpose of what I want.
Now if the motor has a 3/4 shaft I could probably rig up a 3D clutch on it too but that's gonna get really complicated and expensive really fast. Maybe some setup involving a jackshaft?
 

karl

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Good to hear from ya! Welcome back!

From what I understand , your going to need a one way bearing or a clutch that is controlled
by whatever means to do the business.

Bud at work got a quote, $300 a pop for custom sprag bearings to replace
the front differential. Baja SAE.

But if your not putting them on the final drive, like have a jackshaft with a top speed ratio
between the gas motor and shaft, and more reduction with the electric motor , and one way
bearings on the jackshaft electric sprocket, it may be more feasible, much less torque.

Problem is off the shelf bearings are metric , and rather difficult to implement unless you
have a machine shop. Cool idea, hopefully someone has a better solution!
 

JTSpeedDemon

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Yeahhhhh for $300 I'll just get another 3D clutch to set up on the electric motor.
Another idea I came up with is to put the electric motor with a gear adduction to a jackshaft which will have a low stall clutch on it, which then drives to the axle.
So the motor would have a big sprocket going to a clutch mounted on the jackshaft with the 1550 RPM yellow Max Torque spring. So I would have to spin up the electric motor a bit to engage the clutch but otherwise it would stay disengaged. Then the real problem is getting the low gear ratio I want, I'd like to avoid a dual jackshaft system if possible.
So far though I've concluded it has to have a way to disengage both drivetrains separately. So the Raptor will get a 3D clutch, but the electric setup is a bit trickier.
The ideas I have so far for the electric disengage is:
Jackshaft/centrifugal clutch
3D Motorsports clutch on the electric motor
Belt pulley clutch
Not a big fan of having a belt though, and belt clutches aren't the most space efficient, which could pose a problem on the back of a race kart.
 

Functional Artist

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Howdy :)

I've kinda thought about something similar to what your proposing, a while back
...but, ALL electric, of course ;)

I was thinkin' a (2) speed kart (low gear & high gear)
Low Gear
(1) motor would be connected to the axle with a 6:1 GR

High Gear
(1) motor would be connected to the axle with a 4:1 GR

The things that I thought would cause the most were
...like you mentioned the "drive train" part of it (& the associated issues)
...& then also, the controls

Separate controls would be needed
...& then those controls would have to be, manipulated properly :thumbsup:
 

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JTSpeedDemon

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Howdy :)

I've kinda thought about something similar to what your proposing, a while back
...but, ALL electric, of course ;)

I was thinkin' a (2) speed kart (low gear & high gear)
Low Gear
(1) motor would be connected to the axle with a 6:1 GR

High Gear
(1) motor would be connected to the axle with a 4:1 GR

The things that I thought would cause the most were
...like you mentioned the "drive train" part of it (& the associated issues)
...& then also, the controls

Separate controls would be needed
...& then those controls would have to be, manipulated properly :thumbsup:
Yeah the controls are actually the least of my concern right now lol, I'm thinking a pair of clutch levers on the back of the steering wheel and a thumb throttle for the electric. But that's all moot if I can't get the drivetrain set up.
Also what's your recommendation for a good electric kit to use?
 

Functional Artist

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Yeah the controls are actually the least of my concern right now lol, I'm thinking a pair of clutch levers on the back of the steering wheel and a thumb throttle for the electric. But that's all moot if I can't get the drivetrain set up.
Also what's your recommendation for a good electric kit to use?
Yup, the drive train will be kinda complicated :unsure:

Also, keep in mind that you would be doubling your weight adding the batteries & all :eek:

Well, for the biggest & best "bang for the buck", I always go with the MY-1020 48V 1,000W brushed motor kits (~$125.00)
1000 W 48V electric scooter motor kit w BASE+control box key lock & Throttle | eBay

I've used 'em on many karts
...their little beasts ;)
 
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