Quad build.

Plans change by the day, but finally made a decision.
My first Trike will be the bace for a quad.
Indipendend suspension in the rear.
20 inch all around.
Motor will be, behind the seat.
Underseat steering.
I will be using the seat from my second build and make that I also can mount the HP velotegnic seat.
Rear will be longer with a plate on top, so I can transport stuff.
Also Ada big solar roof. It will be heavy, but the quad gets a 48v 500w controler with a self build battery. It will be possible to connect 48 and 36v batteries.
Then there will come a trailer. The trailer will be in 2 parts. Bottom to carry stuff and a part that will replace my bicycle caravan.
Bigger and more luxery.

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I start the coming weeks with designing the rear of the quad.
All behind the seat will be gone and front will stay as it it with some changes to the steering and seat.
Also new wheels in front.

I wanted to build again and I wanted a quad. 2 trikes and a quad is a bit to much. This is a nice solution and I will also be able to build a new caravan. I will probably cell the one I have now after I get back from my holiday.
 
Here is a sketch of my plans.
Front stays the same as my trike has now, but the rear will change a lot.
Hub motor with a one way sprocket on it. I turn the wheel around, so the one way is on the other side. This way it gives power and as I am out of battery, I will not have any resistance of the motor.
An other advantage is, is that I can use a different size gear, so it isn't 1 on 1. As I put a smaller gear on the axle, than on the motor, then I get a bit less top speed, but the quad will be able to pull more.

Rear wheels have indipendend suspension.

On the ends of the long shaft, are 2 one way's. This makes that I don't need a diff and also keep power even as one wheel goes of the ground.
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The motor further behind and the batteries behind the motor, make that I keep some pressure on the rear wheels as I have no load.

Controller will be a 500w that can run on 36v and 48v.
Motor will be a tesla motor that is on a bike I have stsnding here. I can easily go to 800w with this motor, but 500w is more than enough. Especially as I gear it differently.
The quad doesn't need to go as fast as my trike. It must be able to carry a lot.
 
Emeil

These may have some good ideas ?

SH32 from Finnish forum

Pedal powered 2CV Finnish forum again

Both Quads with suspension

Paul

Hi Paul,

I like the first one. Nice design, only not for me.

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Mine will be different, because I will sit lower and the rear suspension will be different.
But the concept is about the same.

The rear has the option to Cary stuff, or just like this one, pull a trailer/caravan.
I also want to build a new caravan, but I start with the quad.
 
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Made the first sketch in fussion360.
Tomorrow I will work it out further to a 3d model.

Yellow is what I have. That is why I kept the front out.
Purple is seat mount. I dezide the location with the seat. Light gray is arm where the wheel is on.
This way I have indipendend suspension.
Small dotted circle is gears and big one is the hub motor.

This design has now a wheelwase of 1116mm.
From one side nice, but the plate is now only 60cm long. I want this longer. I can more to the front, but I think I ad a bit more wheel base length.

I will post the 3d model as I worked it out further.
 
Emeil

Which bit do you call the ' plate ' ?

Is longer bad ?

What about making the seat mount stronger and suspending the wheels from there ?

Paul
 
As I put a smaller gear on the axle, than on the motor, then I get a bit less top speed, but the quad will be able to pull more.

Other way round Emiel. Does the motor itself have a gearbox? I'm not familiar with a tesla motor for a bike and the internet throws up no matches either.
 
Emeil

Which bit do you call the ' plate ' ?

Is longer bad ?

What about making the seat mount stronger and suspending the wheels from there ?

Paul

The plate is the line that is on top of the red part.

No longer isn't bad. I didn't expect to have such a short wheel base. I will make it 150mm longer.
I can make the wooden plate on top longer in both directions. I can fix it to the back of the seat mount and let it stick out over the wheels. That will give me a bigger luggage space.
 
Other way round Emiel. Does the motor itself have a gearbox? I'm not familiar with a tesla motor for a bike and the internet throws up no matches either.

Tesla motor is the type of motor. It is a motor without internal geering.
It has 3 wires and some have also sensor wires.
You can change the direction of the motor, by switching 2 of the 3 wires. It doesn't matter wich 2 you switch.

This is a rear hub motor. I can mount a single geur to it. Because I can change the direction that it runs, I can turn the motor around, so the f gear is on the other side.
 
Here some renders of te concept I made.
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Things will change, but this is the concept.

The gray front stays as it is. I will use that from my old Trike.
The blue is the mount for the seat.
The grean is the mount for the plate that comes on top.
The yellow parts are the arms for the rest wheels.
The red is the part that holds the back together.

There come some extra parts to strengthen the frame. The back of the seat mount, will be connected to the plate that comes on the grean parts.
Aldo there come some extra parts to connect the gray to the red. Just to make it more stable.

Motor comes behind the gears that are in line with the rotation point of the arm.
The battery will come behind the motor.
48v 2kwh battery is what I want to build.
The controler will come behind the seat.
I will probably cover everything, so it looks cleaner in the back.

It seems that this will work.
It will not be the lightest quad, but with the relatively short wheelbase and the low center of gravity, it will be fast.
I will slow it down, by using an other gearing on the motor. This way I get more power and less top speed.
But I can always change that if I want.
 
Emiel

Nice

Why not rotate the blue seat part through 90' and weld it to the red suspension mounts ? make the rear area behind the seat more useful without that backwards facing stay ?
What lives between the red horizontal rear frame and red plate , ie around the green mounts ?

Paul
 
Emiel

Nice

Why not rotate the blue seat part through 90' and weld it to the red suspension mounts ? make the rear area behind the seat more useful without that backwards facing stay ?
What lives between the red horizontal rear frame and red plate , ie around the green mounts ?

Paul

I as trying to make the connection between red and gray strong, but I can look ad that way also.
I didn't think of that, but I surtenluy look in to it.
It will make that part also stronger.
 
These interesting posts remind me of when I became an AZ member about a year and a half ago.
The three of you were in the habit of creating- trouble shooting-and providing alternatives. Good stuff.
Nice to see you posting your build ideas again Emiel.
Cheers
 
If the forward platform mount in green is joined to the blue seat mount some triangulation is achieved. Same with extending that same forward platform mount to the top of the rear suspension mounts. Very little extra chassis would be needed to add a lot of strength in those two points. From the point where the seat mount then touches the green I'd add two diagonals back to the rear of the lower red. That cargo platform is all currently cantilevered and those diagonal braces will triangulate it substantially. They would be in almost perfect tension so could be relatively light.
 
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Thank you Velocoupe.

I lower the plate Popshot and do that. I probably combine the seat and the front green mount.

I will use trespa as plate. It is heavy, but my quad stays outside, so it needs to handje the weather.
 
I took some measurements from my trike and I need to change the wheelbase. It is now 1m, but it will be 1,2m.
I also made a concept caravan. Just to see how it works.
I made it so I can make 1 or 2 seats with a table in between.
The rear of the caravan will not be rounded. This way I vcan mount 2 solar panels I have on top and one will come on my quad. Then I have 300w and better aimed ad the sun as I have now.

The quad with sind small changes. Lower plate and mounting changed.
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The quad with the caravan.
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The nice thing is, us that this combo is about the same length as what I have now. Even a bit shorter and still I have more space incide.
A bed that will be about 90cm width VS a 60cm and I can sit with 2 people in it and have a table.
 
Wow so much to discuss , now we can see your excellent renderings.

Can I ask about the rear suspension ?
How do you plan on implementing it ?
e.g is there a rule of thumb for how long to make the swing arms ?
What are you using for suspension units ?
how will you cope with the huge differences in weight between the quad on lt's own and with the caravan mounted ?

On the caravan where is the sleeping area the floor or the seat bases with the table between them ?

Paul
 
Wow so much to discuss , now we can see your excellent renderings.

Can I ask about the rear suspension ?
How do you plan on implementing it ?
e.g is there a rule of thumb for how long to make the swing arms ?
What are you using for suspension units ?
how will you cope with the huge differences in weight between the quad on lt's own and with the caravan mounted ?

On the caravan where is the sleeping area the floor or the seat bases with the table between them ?

Paul

I mount the springs as the Trike is almost finished. I ad more mounting options, so I can adjust it.
The length of the arm has influence on what strength spring you need, but with the lengths I do, it isn't that big of a deal.
You want the springs go in about 20 to 30% as you sit on it.
For me the suspension is for comfort. It isn't for off-road. Here the roads are smooth, so it is for the small bumbs. Therefore I don't need mutch travel. By making the arms longer, I also get a bit more trafel for the wheels.

The weight of the caravan isn't that much that pushes on the quad. The caravan will be heavier than what I have now, but it will only be heavier to pull. I put my stuff on the axle of the caravan and so that it is slightly heavier in the front.
That is why I also didn't put the wheel al in the back.
It will add some extra weight, but if needed I can adjust the tebtion on the springs a bit and as it is really needed, I can get heavier ones.

The table will fill the gab in between the seats.
Just like the big caravans have. The back of the seat that is above the wheels, will fold down.
Then I have about 2m in length and just under 90cm of width, to sleep on.

I only put luggage onder the seat that is above the wheels. My sleeping stuff will be behind x that seat.
I will also put some stuff on the quad. There comes a plate where I connect my caravan to, that sits on top. So under it, I have a small space to put my clothes and water.
 
Plans keep changing. Front will also be new. I will build 2 quads together with person where I build my quad. He wants one to and as they both are ready, we probably build 1 or more quads. It seems that more people are interested here when they had seen the renders.

The front will be new to. It gets front suspension. I didn't want to do this, but because it is a quad, it is better. This way, the 4 wheels stay better on the ground.

The front gets triangle arms. 2 on each side and a dampener in between each side. Simple construction, but it works.

Other thing that changes us the motor. The man with who I build them, has 2 1000w motors that are the same, so we use them.
The quads get a 500w on 48v controler and is geary in a a 1 to 2 ratio. This makes that it gets more power to the wheels and uses a bit less of the battery. The top speed will be lower, but it isn't a racer. Comfort and power to pull my caravan is what it needs to do.
 
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