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Discussion Starter #1
Hi, Just joined to hopefully learn more about home built Electric cars for a little of marketing research on my home built Trike project that I hope to be building and selling in the next year are so.

Thanks
 

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Discussion Starter #3
I assume that this is the Magnum S6R (and YouTube: Magnum S6R Body Plug Build). Are you considering a electric version of this design as an alternative for builders, or switching from the bike engine to electric?
Yes, the way I have it designed it could be done with any of them.I am sure a FWD electric car motor like from a Leaf or Volt will fit right in and probably take this thing for a ride. It is designed for FWD transmission bolted to a BMW inline 6 engine.I did a design study several years ago when Yasa first came out with their in wheel motors but found out that they would not be selling to the public so I had to let it go and went back to the gas version.
Recently I came across some info on a couple of Electric car motors and was impressed with the numbers enough that I started thinking about the possibilities and then realized that I didn't have to change my design to do it because I'm already set up for the same style layout.
I am trying to stay away from the bike engine stuff with this design because I fill like the car would be to big for any bike engine.
 

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I am sure a FWD electric car motor like from a Leaf or Volt will fit right in and probably take this thing for a ride.
Yes, the motor and transaxle from any common production EV will be more than powerful enough to be sufficient for a vehicle of this size.

The Leaf is a common and rational choice.
The Volt is a plug-in hybrid - are you considering a hybrid (which would present a huge problem packaging everything in) or thinkin of the Volt transaxle as an electric-only drive unit? The Volt transaxle is overly complex to use without an engine. Or perhaps you mean the Bolt; strangely used the most "electric" name for a hybrid, and used "Spark" for an interim EV, leaving "Bolt" for their first mass-production EV.
 

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The details of the eventual electric drive design can be left for separate discussion threads or a build thread, but just to satisfy my curiosity (and perhaps help us understand your approach), I was wondering about the original configuration with the engine...
It is designed for FWD transmission bolted to a BMW inline 6 engine.
This is an unusual choice. Inline-6 engines run smoothly and are generally very desirable, but they are long and heavy. They are almost never used in a transverse configuration due to the length; the Volvo SI6 engine is the notable exception, but it was designed specifically to be as short as possible and any BMW engine is not. Any transaxle stuck on the end of a BMW inline-6 makes a very wide package; placed where it is in the Magnum 6SR it doesn't need to fit between front wheels and suspension, but it's still wide.

There are motorcycles with inline-6 engines mounted transversely, but they use a transmission behind the engine, driven by parallel gears from the engine, not a transmission in line with the engine.

There's also the small challenge of finding a transaxle with the same bell housing bolt pattern as the BMW engine, but perhaps BMW uses the same pattern on their rear wheel drive cars and the Mini or front wheel drive 1-series.

Presumably the plan is (or was), assuming a transverse transaxle that places the engine on the right-hand side, to run a chain or belt from the right-side transaxle output and to lock the differential.

The rendering at KitCarLinks shows what looks like a dual rear wheel, perhaps even with a control arm and belt or chain drive to a hub between the wheels. Is that really the plan?


And on the subject of suspension... Riley's Tri-Magnum uses a Beetle suspension with the occupant's legs over top of the suspension crossmember and springs - what's the plan for this design? I assume it is a modern suspension ahead of the occupants' feet.
 

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I am trying to stay away from the bike engine stuff with this design because I [feel] like the car would be to big for any bike engine.
I generally agree that bike engines - and transmissions - are unsuitable for cars. On the other hand, the engine and transmission from a heavy bike isn't far off matching a very light car like this. Riley's choice of the Gold Wing powertrain for the Tri-Magnum wasn't unreasonable, and companies such as Compagna still use large bike engines for their trikes. I assumed this was a BMW K-bike engine when first saw "BMW", and I think that (a 1.6 L which drives a 320+ kg bike) wouldn't have been a bad choice.

As an EV, salvaging a motor and transmission from an electric bike might seem obvious, but existing EV bikes are not heavy and their components would probably not be suitable. There's nearly no supply of them to salvage, anyway...
 

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Discussion Starter #8
Yes, the motor and transaxle from any common production EV will be more than powerful enough to be sufficient for a vehicle of this size.

The Leaf is a common and rational choice.
The Volt is a plug-in hybrid - are you considering a hybrid (which would present a huge problem packaging everything in) or thinkin of the Volt transaxle as an electric-only drive unit? The Volt transaxle is overly complex to use without an engine. Or perhaps you mean the Bolt; strangely used the most "electric" name for a hybrid, and used "Spark" for an interim EV, leaving "Bolt" for their first mass-production EV.
Thank you for your interest in my project Brian. And yes the Leaf or the Bolt motors make the most sense I just said Volt by mistake.
 

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Discussion Starter #9
The details of the eventual electric drive design can be left for separate discussion threads or a build thread, but just to satisfy my curiosity (and perhaps help us understand your approach), I was wondering about the original configuration with the engine...

This is an unusual choice. Inline-6 engines run smoothly and are generally very desirable, but they are long and heavy. They are almost never used in a transverse configuration due to the length; the Volvo SI6 engine is the notable exception, but it was designed specifically to be as short as possible and any BMW engine is not. Any transaxle stuck on the end of a BMW inline-6 makes a very wide package; placed where it is in the Magnum 6SR it doesn't need to fit between front wheels and suspension, but it's still wide.

There are motorcycles with inline-6 engines mounted transversely, but they use a transmission behind the engine, driven by parallel gears from the engine, not a transmission in line with the engine.

There's also the small challenge of finding a transaxle with the same bell housing bolt pattern as the BMW engine, but perhaps BMW uses the same pattern on their rear wheel drive cars and the Mini or front wheel drive 1-series.

Presumably the plan is (or was), assuming a transverse transaxle that places the engine on the right-hand side, to run a chain or belt from the right-side transaxle output and to lock the differential.

The rendering at KitCarLinks shows what looks like a dual rear wheel, perhaps even with a control arm and belt or chain drive to a hub between the wheels. Is that really the plan?


And on the subject of suspension... Riley's Tri-Magnum uses a Beetle suspension with the occupant's legs over top of the suspension crossmember and springs - what's the plan for this design? I assume it is a modern suspension ahead of the occupants' feet.
The reason the in BMW engine was chosen is because I like the way the way it leans away from the firewall allowing me to move it further forward ( in theory) to help with the center of gravity and also their cheap and plenty full.The FWD transaxle would have to be adapted to the engine.

Yes it is wide but it does fit where I have it placed within the Cars frame there is a critical dimension on the transaxle placement that can only moved to the left so no matter which power train is used the transaxle stays in the same place.

Yes the engine will point to the right and the spider gears welded or a spool.

I decided to put two wheels close together for economic reasons, when I started looking at tires and wheels I realized that a 20x13 rim are very expensive plus a 345/25/20 tire at this moment are close to $1000.00 each so that was going to and being like $1200 to $1500 just for the rear. So I changed it so all of the now 4 wheels are the same size and a whole set is $1200 to $1500, plus another interesting thing is what I call spare on the ground if theirs is a flat on front you take one of rears off put on the front to limp home that way I can leave the cargo space up front usable for other things.

The rear drive on Kitcarlinks was designed to use the transfercase chain from a full size Chevy 4wd and is a usable design and would be very robust even to upwards of 500 hp.
I am currently considering a different design that would be lighter and easier to build, I currently have 24 rear control arm designs and have put 7 of them on the ground on my other car which is a Tri-Magnum.

I have several front suspension designed for this car to which some tilt slightly to cam the back tires in the correct direction I can't figure out how to make it reacted fast enough ( I saw where Audi is working on this also using a split swaybar and an electric motor to tilt the car into the turn.The design I am using on the prototype is base on the Ferrari F355, I found a paper discussing the hows and whys plus plotted all the pivot points for control arms steering linkages shock position everything, so I pulled the drawing into my cad program and cross bred it with a C5 Corvette Bearings calipers. I figure that would be good enough for me.
 

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Discussion Starter #10
I generally agree that bike engines - and transmissions - are unsuitable for cars. On the other hand, the engine and transmission from a heavy bike isn't far off matching a very light car like this. Riley's choice of the Gold Wing powertrain for the Tri-Magnum wasn't unreasonable, and companies such as Compagna still use large bike engines for their trikes. I assumed this was a BMW K-bike engine when first saw "BMW", and I think that (a 1.6 L which drives a 320+ kg bike) wouldn't have been a bad choice.

As an EV, salvaging a motor and transmission from an electric bike might seem obvious, but existing EV bikes are not heavy and their components would probably not be suitable. There's nearly no supply of them to salvage, anyway...
This car would weigh approx 1800 LBS ( 816 kg) It has a full interior with the cockpit measured from a 1989 Ferrari Mondial T I had in my shop for two years.
There are two full seats dash console and is designed for AC.
The biggest problem with bike engines is not enough low end torque so when you use one you have to ride the clutch a lot to get it moving but after that they are OK. But the lack of a good way to do reverse is really the part I don't like, the electric reverse is to jerky for me because the back of these cars taper a lot so when you look in your side mirror and you see nothing and the seats are holding your body so you can't turn around very well so basically your driving blind when in reverse.Its a weird feeling but no different than any small sports car.

If you would like to discuss the design further I guess I will start a thread in another part of the forum.
Thanks Brain

Greg
 

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Sorry, somehow I missed these replies to my comments...

The reason the in BMW engine was chosen is because I like the way the way it leans away from the firewall allowing me to move it further forward ( in theory) to help with the center of gravity and also their cheap and plenty full.The FWD transaxle would have to be adapted to the engine.
The BMW engine choice is not relevant to the EV version, so I'll try not to dwell on it, but in my part of the world nothing with "BMW" on it is cheap. That transaxle adaptation is not trivial; you could probably buy an engine with a manual transverse transaxle attached for about the same price as a BMW engine plus an adapter... and still need to pay separately for the transaxle.

With an electric motor you don't need a multi-speed transaxle, and can use whatever single-speed transaxle comes with the motor that you choose, if you choose one salvaged from a production EV.

Yes it is wide but it does fit where I have it placed within the Cars frame there is a critical dimension on the transaxle placement that can only moved to the left so no matter which power train is used the transaxle stays in the same place.
This appears to be an exceptionally wide body.

Yes the engine will point to the right and the spider gears welded or a spool.
Thanks for the confirmation.
 

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I decided to put two wheels close together for economic reasons, when I started looking at tires and wheels I realized that a 20x13 rim are very expensive plus a 345/25/20 tire at this moment are close to $1000.00 each so that was going to and being like $1200 to $1500 just for the rear. So I changed it so all of the now 4 wheels are the same size and a whole set is $1200 to $1500, plus another interesting thing is what I call spare on the ground if theirs is a flat on front you take one of rears off put on the front to limp home that way I can leave the cargo space up front usable for other things.
This will not work the way you are hoping.

The dual set in the rear is far too wide, due to the extra sidewalls and the space between them, which you have apparently made very wide by putting the suspension are between them. When the vehicle leans, this tire pair will lean with it, and the tire on the inside of the turn will not be in proper contact; dual tires are never used on independent suspensions, for good reasons.

There was actually a classification for this arrangement, at least in the old days of European microcars, which considered a four-wheeled vehicle like this to be a three-wheeler for regulatory purposes if the rear track (tire spacing) is narrow enough. They were not built this way because they worked well, only to be cheap and to dodge the rules for proper four-wheeled cars.

"Limp" is certainly the word in case of a failure. In any dual tire setup the tires never share load equally, because they are never perfectly matched. If you look at light and commercial truck tires, they have two load ratings: one for use as a single tire, and a lower one for use as part of a dual pair. When a tire in a dual set fails, the other one is instantly overloaded and is likely to subsequently fail.

A spare is unnecessary, even with just three wheels and no runflat tires. Just carry an air pump and a credit card - flats in modern tires are so rare that it's not worth worrying about.
 

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This car would weigh approx 1800 LBS ( 816 kg) It has a full interior with the cockpit measured from a 1989 Ferrari Mondial T I had in my shop for two years.
There are two full seats dash console and is designed for AC.
Ah... heavy for a sport trike, and so too heavy for bike engines.

... the lack of a good way to do reverse is really the part I don't like, the electric reverse is to jerky for me ...
I agree that reverse is a problem with bike transmissions in general. The electric reverse is only jerky if it is just on-off, and I can believe that bikes have something that crude. With an electric vehicle reverse can simply be running the motor in the reverse direction, with normal power control, so that concern goes away... although in this case that just means that you don't need a reverse gear, not that you would consider a bike transmission.

If you would like to discuss the design further I guess I will start a thread in another part of the forum.
Yes, definitely start a build thread when you're ready to start the electric vehicle design, or technical discussion threads for specific design issues or questions that you might encounter.
 

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I have several front suspension designed for this car to which some tilt slightly to cam the back tires in the correct direction I can't figure out how to make it reacted fast enough ( I saw where Audi is working on this also using a split swaybar and an electric motor to tilt the car into the turn.
Do you mean camber the vehicle into the turn, as in slightly leaning into the turns? Yes, automated control of that would be difficult; you would probably need to respond to lateral acceleration with feedforward control, not react to lean angle with feedback. The split swaybar idea has been around forever - it would take a lot of torque and significant power.

Leaning in would not be desirable with the dual rear wheels anyway - for that I think you just want to corner flat.

In the active suspension experiments of the 1980's (yes, this was all done long ago, as soon as computers were compact enough) drivers found that rolling (leaning) into corners was disconcerting and allowing slight outward roll provided the best feedback to the driver.

The design I am using on the prototype is base on the Ferrari F355, I found a paper discussing the hows and whys plus plotted all the pivot points for control arms steering linkages shock position everything, so I pulled the drawing into my cad program and cross bred it with a C5 Corvette Bearings calipers. I figure that would be good enough for me.
Just to be clear, this would not lean into the turn, or actively control roll. I'm sure that the F355 design is good; the C5 design would be similar... why not just use it?
 

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Discussion Starter #15
Sorry, somehow I missed these replies to my comments...


The BMW engine choice is not relevant to the EV version, so I'll try not to dwell on it, but in my part of the world nothing with "BMW" on it is cheap. That transaxle adaptation is not trivial; you could probably buy an engine with a manual transverse transaxle attached for about the same price as a BMW engine plus an adapter... and still need to pay separately for the transaxle.

With an electric motor you don't need a multi-speed transaxle, and can use whatever single-speed transaxle comes with the motor that you choose, if you choose one salvaged from a production EV.


This appears to be an exceptionally wide body.


Thanks for the confirmation.
Hey Brian sorry for the delay, you have so many questions I don't know where to start, so here we go. BMW engines are plenty full in America, My theory on that is it is due to the income tax structure in America. If you have any children and whether you have an income or not when you file taxes the government will send you a very large check so lower income families get a blast of cash most times in February or March and most people use that money to buy a a car that they can't afford such as a BMW and usually it will break down on them and end up at a mechanic shop where they get the bad news about how much the repair is going to be so they basically abandon the car till the next tax season and start the process all over again. Now these cars will sit at a shop for a while until they haul them off for scrap and some of them end up at a pull it yourself type yard where the car may have a bad transmission but engine is ok so in my area I can the get the whole motor with accessories and wiring and computer for about $250 take it out myself. I have a Bodyshop, Fab shop and Machine shop. I do it all. And yes I understand the e version will not need a trans axle accept for maybe reverse ( this is really why I'm here is to gain a much better understanding of the different concepts and possibilities. I'm really open to anything. My design is the same width as a H1 Hummer. I had one in my shop that belonged to my local Police department and as looked at I thought if this thing is legal to go down the road I should use it.
 

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The transaxle isn't needed for reverse, because the motor can be reversed electrically.

This design is very wide. I don't know why anyone would want that width, but it does provide room for a long transverse engine.
 

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Well, what it mainly does is create room for your feet and pedals plus master cylinders because they are located inside the wheels and I didn't want to be twisted sitting the car. If you check the specs on a Bugatti Chiron you'll find that its 2038mm wide and a Aventador is 2030mm in the front and I would believe that they did this to create room for the feet and the pedals and to kept the driver from being twisted while driving and for the stability, as I remember this a problem in the Diablo. So I thought wider is better, in America I can actually be 2438mm (96 inches ) wide and be legal to drive on the highway.

I searched for a front suspension that would work straight off of a car that someone could buy cheap and be done it just didn't exist, mainly because of the steering racks are all in the wrong place for my design.

Thanks Brian
 

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Well, what it mainly does is create room for your feet and pedals plus master cylinders because they are located inside the wheels and I didn't want to be twisted sitting the car. If you check the specs on a Bugatti Chiron you'll find that its 2038mm wide and a Aventador is 2030mm in the front and I would believe that they did this to create room for the feet and the pedals and to kept the driver from being twisted while driving and for the stability, as I remember this a problem in the Diablo. So I thought wider is better, in America I can actually be 2438mm (96 inches ) wide and be legal to drive on the highway.

I searched for a front suspension that would work straight off of a car that someone could buy cheap and be done it just didn't exist, mainly because of the steering racks are all in the wrong place for my design.

Thanks Brian
Racks are commonly in front of the axle line (the configuration called "front steer") for front-engine designs, particularly those with the engine set back and low (so the rack can be in front of the engine rather than under it). Of course most passenger cars now have front transverse powertrains, in which the engine is ahead of the axle line and so the rack is always behind it (rear-steer) and even front longitudinal engine designs can have a rack mounted behind the axle line if the engine sits high enough. The Corvette is the most obvious wide-track front-steer double wishbone suspension, although it isn't quite this wide (to get more track width, people widen the front subframe or build their own mounts on the frame for the control arm pivots); the Mazda Miata is the common example at the small end of the size scale.

Yes, putting the occupants feet between the wheel housings causes this packaging problem (of needing a lot of width, and a front-steer configuration). It is only common in vehicles which place the engine behind the occupants, as the designer attempts to manage the lack of sufficient wheelbase to package both the occupants and the powertrain.

The problem with the width isn't legal - it's frontal area and sheer inconvenience when driving. The frontal area doesn't matter so much when you have several hundred horsepower and the owner doesn't care about fuel consumption.
 
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