AWD Quad build in planning: "Satanic Panic"

The Toecutter

100 kW
Joined
Feb 8, 2015
Messages
1,478
My parts to convert a trike into a quad arrived over a week ago.

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I really like the KMX as a build platform. I've made an EV out of one already and would like to keep it operational. I have a kit that would allow for me to convert it into a quad, but I'd rather build another one than change a good, functional one thus removing it from use for an indeterminate period(I have limited time to work on it, yet use it regularly for transportation and thus want to avoid taking it apart).

My overall plans for this quad are as follows,

AWD streamliner with the seat reclined as far back and as low as possible while still being able to see over any bodywork that would be around my pedaling area is the goal. With the seat reclined far back, it will force my boom in as far as it will go, as if I was a very short rider. I'd need short 110mm crankarms that allow fast cadence to assure proper ground clearance for my heels over the road(I want at least 5"). I'm thinking I will have the top of my helmet somewhere around 800mm off the ground, which will keep this very low with a racecar-like center of gravity, and keep the frontal area low in spite of being a quad. The goal is a weight distribution somewhere around 45F/55R.

Regarding shape, it will be much like an Auto Union Type C streamliner viewed from the top and front, except with a big front bulge in the center of the front to accommodate my pedaling. Unlike the Type C, the front wheels will likely be fared on top and exposed for the bottom 2/3 of the wheel(think 1953 Alfa Romeo Disco Volante Coupe), since I need to be able to turn. The rear wheels are going to be fully faired on the outside and mostly fared inside(inside, there will be clearances cut to allow differential and subframe assembly to move up and down with the rear suspension, and spandex boots will be made to maintain aero while allowing movement). The rear of the vehicle will be a downforce increasing Venturi tunnel doubling as a rear diffuser(see 2025 Renault Folante concept for what this could look like from behind), which accepts air from the vent holes in the rider cabin, air initially entering the vehicle through the stagnation point air intake used to cool the rider as well as any open windows or raised windscreen. Part of the plan would include a full rollcage and a gullwing door, with crumple zones. 16x1.5" DOT rims and 16x2.25" Mitas MC2 tires all around.

Gearing will be a 11-34T DNP Epoch in the back with a Schlumpf HS triple up front, with a cadence sensor for PAS. The limited required chainwrap capacity should allow for me to get away with using a short cage rear derailleur in order to minimize ground clearance issues while retaining a wide gearing range.

I'm considering making a rack-and-pinion steering for it, where I can turn the wheels maybe 20-30 degrees in each direction with a 50-70 degree turn of the steering wheel in either direction, using a butterfly steering setup, with brake levers and trigger shifters placed on this system. This will facilitate allowing most or all of the front wheels to remain fared by the shell design while keeping frontal area low, at the expense of having a larger turning radius.

The EV system would be a 6kW Cyclone middrive running 10kW peak driving the rear wheels, with Grin All-Axle 3T wind front hub motors at 6kW peak in each front wheel. This would be powered initially by a Phaserunner for each motor at reduced power(maybe 4 kW each, 90A to rear motor, 45A to each front motor) and later by an ASI bac2000 for each motor at full power, the three controllers all run by a CA3 with a high current shunt. The battery would be a 20S6P pack of Molicel P50b or whatever are the most energy dense cells I can find that make the requisite power by the time I am ready to make the pack.

Solar panels would cover as much of the body as possible. Maybe up to 400W worth of them.

Since KMX are no longer being made, and since the spindle is the weakest mechanical part of the design, I am heavily considering an alternative front suspension to the one I used and Adam Roy designed:

UTCustom KMX Front Suspension Upgrade
UTCustom Ackerman Compensator Steering Upgrade
UTCustom Revolution EC34/30 Headset for Sunseeker Trikes (each)

This alternative design uses spindles from a Sunseeker, which are readily available. Only 1.25 inches travel, not as wide of a front track(advantageous in my case for aero, since by going quad I don't need a massively wide front track to corner at high Gs), but unfortunately they are not gas shocks ad I will lose the 3 degrees negative camber.

I think they are still compatible with these brakes, however:

https://kmxsuspension.epizy.com/Trike Twin hydraulic disc brake.html

And I'd install a gas shock in the rear also, so that I have a full-suspension quad.

All I have to do is find another KMX to butcher.

It will cost me about $5k all in just to build the functional but unmotorized quad, and $7k to complete it to the aforementioned specs.

I'd prefer to have replacement OEM 3rd gen KMX spindles and Adam Roy's front gas suspension, but it doesn't look possible to obtain spindles at the moment. If I can find a KMX with the proper spindles, find a source for the right kind of spindle, or find someone who can make replicas of the spindles I have in my possession, I will go this route instead of the Sunseeker suspension. No matter which I choose, front track will be wider than rear track, which will help facilitate a more teardrop-shaped shell.

In either case I'll keep my existing 3-wheeled KMX with full suspension, 3rd gen spindles, hydraulic front brakes, AVID bb7 rear brake, and 10kW to the rear Leafbike 1500W 3T motor as it is, and pursue no AWD upgrade for it. I'd rather have AWD in a quad if having to choose between the two. The trike will then be my RWD machine.
 
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I think about Quads all the time. It would be a better hauler or more room to carry items and more room for batteries.
My sticking point is the rear suspension. Would like more an independent rear suspension not a bike rear suspension.
 

The gas shock version of this is my preferred suspension choice, but it is not usable without compatible spindles.

I think about Quads all the time. It would be a better hauler or more room to carry items and more room for batteries.
My sticking point is the rear suspension. Would like more an independent rear suspension not a bike rear suspension.

I'm thinking less of a utilitarian vehicle, and more of a race car disguised as a "bicycle". I want to be very reclined with my mass almost entirely within wheelbase. It will have improved trunk space over my 3 wheeled velo, that being said.
 
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The gas shock version of this is my preferred suspension choice, but it is not usable without compatible spindles.



I'm thinking less of a utilitarian vehicle, and more of a race car disguised as a "bicycle". I want to be very reclined with my mass almost entirely within wheelbase. It will have improved trunk space over my 3 wheeled velo, that being said.
If you move the front tires out to far you will not have enough weight on them.
 
If you move the front tires out to far you will not have enough weight on them.
Depending upon what my weight distribution looks like, I will move my battery and controller placement accordingly to mitigate that if need be. Plus I plan to have hub motors in the front wheels.
 
The gas shock version of this is my preferred suspension choice, but it is not usable without compatible spindles.



I'm thinking less of a utilitarian vehicle, and more of a race car disguised as a "bicycle". I want to be very reclined with my mass almost entirely within wheelbase. It will have improved trunk space over my 3 wheeled velo, that being said.
I'm not going to drive cars anymore once I drag my trike out and start riding it again. BUT, want a short range trike with power and speed to ride to the bank, Post Office and anywhere in the Neighbor hood. That is why I was looking at the KMX frame would be a good place to start, maybe two rear wheels don't need but one gear and three or four motors. Lol. Yes, motors on the front wheels will help and two rear wheels.
 
I'm not going to drive cars anymore once I drag my trike out and start riding it again. BUT, want a short range trike with power and speed to ride to the bank, Post Office and anywhere in the Neighbor hood. That is why I was looking at the KMX frame would be a good place to start, maybe two rear wheels don't need but one gear and three or four motors. Lol. Yes, motors on the front wheels will help and two rear wheels.
If I could get all of the other parts needed to make it work including spindles, I'd have bought that frame.

I am trying to find options to have the spindles in my possession replicated. If I can succeed at that, then I know a used KMX would be a worthwhile purchase.

A lot of components for this have to be available at once for this to work, and each of them is vital to the vehicle's purpose. A KMX allows both adjustable seat angle and mounting location for instance, and has an adjustable boom, which cannot be said for virtually any other trikes on the market. This is important for keeping height, center of gravity, and frontal area down. Full suspension is also required. I need to retain control at high speeds over bad roads.

Basically trying to make a one-seater car prototype with as low CdA and mass as possible while having enough solar panels on it in order to stay moving with minimal need for grid electricity. A 20S6P pack of Molicel P50B would be 2.16 kWh, and if its efficiency was half as good as the Milan SL, I could be looking at 100+ miles range at 60 mph. And it needs to have a ridiculous and dangerous amount of acceleration capability so I can troll expensive/fast cars.

That said, most of its use case will be around 30 mph at low power with pedaling. It will be usable as a "bicycle" for this prototype. Range could be 250+ miles in this use condition, not considering solar. With solar, it might run indefinitely without drawing down the battery as long as the sun is out. Pedaling lightly plus sunlight is all it would need in most cases. This type of layout and the streamlined but flat body shell that can be made for it has a lot of room to fit solar panels without them adding drag. 400W of solar panels making half that for most of the day and another 150W of pedaling would allow one to cover hundreds of miles during the daylight, THEN have a full battery pack ready for night riding. This is a vehicle that might be able to realistically cover 400+ miles in a day on public roads as a "street legal" 28 mph 750W ebike, and then have power left over to run an electric blanket or fan inside as you sleep in it in a Walmart parking lot or similar place.

If this works, I may build an actual car off of the idea without any bicycle parts, and improved over/more robust than anything KMX ever offered. A 250 lb monocoque microcar that could play with supercars at launch in a straight line and out-corner practically everything at speeds low enough that downforce doesn't matter would be sweet. It would be something like a racing kart, except with appropriately sized wheels for street use, full suspension, and electric AWD.
 
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Good luck, would wonder about your projects but I don't. Have been watching you build trikes for 7 years now. Bet your the fastest street rider outside of the motorcycles on here. Your current KMX if more than I need. Can ride less than 4 hrs that limits me to about 50 miles a day. Could get on the out of town roads and fly but that would invite interest from Texas Hwy Patrol. I don't like to get much above 30mph it hurt last time I flipped my trike below 30.

Covered trike with a body shell like the Milan does not need much power to cruse. It's so hot here, could only ride it during late fall to early spring. Unless a AC unit can be used in it. Maybe a cool suit?

Four wheels will give you more stability. My trike is about 4" off the ground this seems to be enough for me. Don't have full suspension, only rear.
 
Good luck, would wonder about your projects but I don't. Have been watching you build trikes for 7 years now. Bet your the fastest street rider outside of the motorcycles on here. Your current KMX if more than I need. Can ride less than 4 hrs that limits me to about 50 miles a day. Could get on the out of town roads and fly but that would invite interest from Texas Hwy Patrol. I don't like to get much above 30mph it hurt last time I flipped my trike below 30.

Covered trike with a body shell like the Milan does not need much power to cruse. It's so hot here, could only ride it during late fall to early spring. Unless a AC unit can be used in it. Maybe a cool suit?

Four wheels will give you more stability. My trike is about 4" off the ground this seems to be enough for me. Don't have full suspension, only rear.
As long as I'm moving, the Milan is cooler than a naked trike anywhere between 80 degrees and 95 degrees Fahrenheit. It's an oven when stopped in these conditions, and even when in motion above body temperature heat. I prefer being enclosed because I don't get sunburnt. It's very comfortable during winter riding.

I mostly cruise around 30 mph in town, but on state highways in rural areas I go faster.

I want to make something that can accelerate from 0-100 mph in 8 seconds or less using full power, while still being (barely)pedalable as a "bicycle" with a dead or disconnected battery.
 
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Lol, right now it's 93 deg F and later in summer will be 110 deg F. We hit 103 deg F two weeks ago. If it did not get above 95 I could live with a torpedo. Always want something like a Milan but i'm too tall and they are to short for me. Think I will get a wind wrap. I'm not in the long distance riding like 5 years ago. Wanted to go see Chalo now he will need to ride down here, lol.

Build a way I will watch!
 
Lol, right now it's 93 deg F and later in summer will be 110 deg F. We hit 103 deg F two weeks ago. If it did not get above 95 I could live with a torpedo. Always want something like a Milan but i'm too tall and they are to short for me. Think I will get a wind wrap. I'm not in the long distance riding like 5 years ago. Wanted to go see Chalo now he will need to ride down here, lol.

Build a way I will watch!
Do keep in mind that I wear a hoodie with long sleeves, leather gloves, long pants, and sometimes a cloak, even when it's 100+F outside. I need gloves so my hands don't slide on the grip shifters with sweat, long sleeves keep the bugs off, and the hoodie or cloak covers me from the sun. With exposed skin, any cooling airflow below the wet bulb temperature should allow some cooling via sweat. I am acclimated to heat. You'd have to try a velo yourself to see if you are comfortable in high heat conditions.
 
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