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I want to build a trike!

280K views 615 replies 40 participants last post by  Woodsmith 
#1 · (Edited)
This project has changed direction due to a change in personal circumstances.
The trike will be a 40mph, 10-15 mile range cargo vehicle for running to local jobs instead of a long fast commute.
It has also changed from a low sleek sports body to a forward control (cab over) layout with a cargo bed.


The new thread is here.
http://www.diyelectriccar.com/forums/showpost.php?p=344007&postcount=616




Having had no time at all to work on either the MR2 or the tractor recently I heard that Duxuk has got his reverse trike (Sparky's garage entry) running and legal.

I went over tonight to meet up with him and to have a chat and a play and boy am I hooked!:D

I had an all too brief drive in it, just up and down a road a couple of times and it is really good fun and with a definate EV grin (though it could have been a grimace against the wind due to not wearing a helmet at speed!;)).

The construction seems to be no more difficult then my tractor and the MSVA (Motorcycle Single Vehicle Approval) inspection seems to be quite straight forward to meet.
I figure that I could build it in my basement, when the tractor is moved outside, and then get it legal and good for local urban driving on the same 48v set up from the tractor but using the 9" motor that I have. I could then move up to 72v or 96v on lead with the option to go straight to LiFeP04. It will cost less to buy lithium for such a light vehicle then it would for the MR2.

I could then sell the MR2 but continue with the 12"motor and MR2 gearbox to make a 4x4 tractor using the diff in the centre to run two Land Rover axles!:D


Anyway, I heard a couple of days ago that I will be teaching again in September so there will be another paypacket!:D
So now I can afford to get my bed room suite (16'x14' bedroom with ensuite dressing room, shower room and bathroom complete with chill out space and laundry) done in the house, design and make the furniture for the bedroom, get the tractor running and ready for body work and then start laying out steel for the trike chassis.:)
 
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#2 ·
Lol, you're a true EV addict Woody! :D I'm going the other way. I sold the D&D motor already, and killed the other street rod project. I am killing the e-bike project as well, and am thinking about selling the 6.7" GE motor. I am considering a small truck for a daily driver, and better tow vehicle for the Inhaler. Trying to get my eggs back in as few vehicles as possible...

So when does this master plan get moving? Why not put the 12" motor in the trike? That would be a great place to do follow up on the art deco theme. I say stick a for sale sign on/list an auction for that MR2, get the tractor finished, and start building the second real Woody EV.
 
#3 · (Edited)
Ahhh, 12" motor in a trike!:D

The motor weighs 114kg, Duxuk's trike weighs 350kg!
To do something similar with the 12" motor wouldn't leave me much to make the chassis with!:D
The 9" motor only weighs 43kg so that would be a saving of 71kg, that's a whole passenger!

I really do think that I would need to go as light as possible just because I only need to move myself and a small back pack to college and the MR2 would just cost too much to get the 70 mile range.
By my calculation I would expect to need 45x200ah LiFeP04 for the MR2 but only 30x100ah LiFeP04 for the trike. That is a significant saving in the pack cost.

If I was to use the 12" I would be really tempted to put it at the front with a shaft to the rear wheel so that the Art Deco comm end cover was out on display. But wouldn't that look great as the front end of a small tractor?


I still have that Yamaha shaft drive rear wheel to play with too.:)
 
#4 ·
I did a bit more weighing of parts last night, just for future records and because I was bored watching tractor paint dry.


The shaft drive motor bike wheel I have weighs 28.4kg
The Lada Niva transfer box weighs 27.4kg

In comparison a rear wheel from the tractor weighs 25kg

So if I were to build a trike, as Jim suggested to me, with the 12" motor, driving the motorbike wheel through the transfer box to get two speeds I would be looking at 170kg just in those parts alone!:D

Now can I build the rest in just 230kg?:rolleyes:
:D

Using the 9" motor would bring that down to 99kg, a bit more reasonable I think.:)

But I think I would be really keen to build under 230kg just to have the option!:D
 
#6 · (Edited)
Why do you need a gear box in a 500lb trike? You're less than half my weight,
Personally I am probably nearly twice your weight!
Oh, you mean the trike.:eek:

You know me and Jim, always searcing for good pulling ratios!;):D

Seriously though it was just a thought that the two speeds of the tbox, 1.2:1 and 2.135:1, would give nice urban and motorway speeds. At 3500rpm I would get 42 and 75mph respectively.
I was also thinking of being able to tow a small trailer, with my tools, to the theatre to save driving the car.

Realistically I wouldn't need gears even if I was using the 7" motor from the tractor. I should have weighed that while it was apart as I could have designed around the 7" and moved one of the other two motors to the tractor.

I have been doing some more weighing (this is going to lead me to therapy!:p) and in a seated position my own weight distribution is 12.8kg at my feet and 72kg at the seat with the remainder of my 86kg in the back rest. Given that I am going to be a significant proportion of the all up weight I figured that this would be useful.

I also want to get my own weight back down to 75kg where it was a couple of years ago. That is going to be harder work then building the trike.

You know, I was more surprised that the motorbike wheel weighed more then the big wheels I have for the tractor. I guess the aluminium rims I found in the scrap steel rims skip at the scrap yard was my benefit.
 
#7 ·
Hi Woodsmith

I had to make the direct drive/gearbox decision for my machine - if you end up with a light weight machine you may find the logic useful

Estimate (guess) motor torque
Multiply through transfer ratio and tire diameter to get force at tire contact patch

Compare to vehicle weight on that tire

If the force is above 80% of the weight you will be able to spin the tire
(super stick drag tires will increase the 80%)

I worked out that I should be able to spin the tires in direct drive - so I did not need to go for a lower gear

Top speed - calculate the motor rpm at you required speed - will it blow up?

I calculated my sort-of-seven would spin tires and not blow up at 80 mph - so no need for a gearbox!
 
#8 ·
Thanks Duncan, that is useful to know.

I guess it will depend on what reduction I have to work with. I must check the ratio on that Virago wheel.
It would be nice to be able to just spin the wheel as I will know I have the max torque available. It is also good for showing others that it 'has some grunt'.:D

I am still dithering over finding the rest of the Virago parts, not knowing which bike the wheel was from, or getting a complete rear swing arm set up in chain or shaft drive from any other bike.
The drive to the wheel will also dictate a lot, chain or shaft. I prefer shaft but will need the whole set up and a means of off setting the drive line or having an angle drive from the motor. Chain is easier to work with, even if I needed a jack shaft.
 
#9 · (Edited)
...Chain is easier to work with, even if I needed a jack shaft.
Chains are messy, but the chain-drive setup would probably be a lot lighter. You can always switch to a belt later, or possibly even find a belt drive setup - though experimeting with different ratios would probably be much more limited and/or expensive.

One thing I always hated about shaft-drive motorcycles is they have a jacking effect. When you get in the throttle, the torque reaction lifts the whole bike. They're quiet and maintainence "free", but I find that to be really annoying.
 
#10 ·
I hadn't thought about the shaft jacking the frame up. I should look at a complete rear end set up anyway as the Virago drive train will include the V twin engine in the same casting.

Here are some photos in the newly vacated workshop to tease Jim with!

12" motor, propshaft tunnel under the seat, transfer box behind to off set the dive to the Virago wheel.:D
Guess who found that the MSVA for trikes allow up to 1000kg!;)



And with propshaft.
 
#11 ·
This is going to be fun! :D

I don't know diddly about reverse trike layout and geometry, so I'll need to ask some possibly dumb questions here. First one:

Won't having the motor that far out in front of the axle center line create funny handling dynamics? I understand that weight is needed on the front wheels, but thought it was always better to keep mass inside the axles.

That being said, the component layout you have there offers the opportunity for really sexy bodywork. It's just begging for a few bumps and curves in the right places! A bomber seat would be awesome. You should make up a mock one with some scrap materials or poster board.

That motor is made for this Woody! I hope the 1000kg limit has created a home for it here.
 
#12 ·
The general idea is to try and get 1/3 weight on each wheel so 2/3 1/3 weight distribution.
All that weight up front would need to be balanced by batteries down the sides putting load to the rear end.

Realistically, as much as I would like to go this route I do want to keep it light so I doubt I will use the 12". Even the 9" is a bit big and weighty by conventional light trike practice.

What I should do is get a couple of Agni motors and fit them at the front pivot of the swing arm.
What I would probably do is fit the 9" sideways to drive a chain, with or without jackshaft, to the rear wheel. I am watching a few chain drive rear assemblies to see if they go for much though I could make my own with a chain drive wheel.
 
#13 ·
Oh well, a guy can dream anyway. Hope you don't mind, but I couldn't resist the temptation to share what I see when I look at your pics! ;) Unfortunately the quality of my chicken scratching is worse than usual. As much as I love my graphics pad it's been really bothering my hand, wrist, and arm to use it and I don't want to end up with carpal tunnel. :eek: I keep experimenting with revised positioning but it throws off my hand-to-eye-to-screen coordination. I feel like I'm drunk trying to draw. :D
 

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#269 ·
That looks damn sexy!

Not that I have any experience in the matter, but is it possable to tip the rear seat back 10° or so. The way the passengers Cg might be lower, and they can tuck their feet in under them a bit, reducing the gap you need between the seats?

This thread has inspired me to add a reverse trike to my long list of things I want to build but never have the time. :D:(
 
#20 · (Edited)
Lol Todd!:D

I have been thinking of the dash board.


This sort of thing would be good with the retro volt and amp meters.
I am considering the possibility of making a wooden version of the engine turned dash panel using small oyster veneers.

I have been measuring the various component possibilities (read 12" motor and transfer box!) to see how things would actually sit. I'd be nervous of too much dead weight and torque with a very light chassis. I might even look at a wood monocoque again.
 
#23 ·
#24 ·
Hmmmm, that transfer box lines up well with the wheel.

The output aligned with the wheel final drive puts the input on the centre line, just right for the motor.:)
Looking good.

It's nice when things fall into place.

I don't know if reason will finally catch up with you, but that 12 inch sticking through the front of the grill with wing fenders on each side sure would look awsome.:rolleyes: Heck maybe even the 9 inch wouldn't look too bad.

We can but dream:D.

Take a real good look at the quad front end I'm using on the Big 13 (i'll send you a hi rez close up if you want). You could widen it very easily. It might not work out for a front motor set up (look at one of the bigger ones if you can find one), but for a rear motor it might just be the ticket.

For a rear motor you could offset the motor to the non drive side and use a chain drive to a drive shaft with a u joint and get a usable ratio.

God I love brainstorming, even at long distance. Most of what I come up with is crap, but I do get a few winners:D.

Jim
 
#25 ·
I was having a close look at that quad front end of yours. It would be difficult with a motor in the centre of it but it may save making wishbones and links.

I was playing with options to keep a rear motor transverse and central with a jack shaft to a chain drive wheel.
I have also thought about the 12" motor at the back with a chain drive to the wheel shaft. The 12" transverse with a jack shaft would be good as it would show off the art deco ends of the motor on both sides.

For weight distribution, and that transfer box, I could place the transfer box under ther seat with the range selector in a 'normal' position either between the knees or cranked off to one side.
I would need to remember not to unlock the diff when the motor is running.:eek:
 
#26 · (Edited)
I did a quick scaled sketch to see how things lay and what the weight distrubution would be.

A number of assumptions had to be made about the front wheel size at 400mm (16") and I left out the other unknown components weight as those can be factored in to retain balance and overall weight later on.

I used a wheel base of 2m (6'7"), a maximum length of 2.9m (9'6"), max width of 1.2m (47") and a height of 1.1m (43"). These constraints are mainly to do with workshop space and trailer space but it may be prudent to increase the length a bit more to get a lower height and better lines.

With a real sized person in and the seat and motor not on the floor the trike profile is a lot higher then the lovely sleek design that Todd came up with.


However, it will surfice for now.
Using the known weights and positions of the rear wheel, 12" motor, myself and 30 100ah cells and a guestimate of about 25kg for front wheels I get a 70/30 F/R weight split. That isn't too far off with the battery pack in two lots of 15 on each side of the cockpit and can change a reasonable amount withthe addition of the rest of the structural and essentail components.

I have removed the transfer box for now as the input is too high and would require me to have a hole in my lower abdomen to let the prop shaft through. It would make getting out a little fiddly if I have to remove the prop first!:D
As it is I have the ground clearence at 4" which is a little low but it is meant to be a tiny vehicle.

I figured a good way to watch the weight is to buy three cheap bathroom scales and put one under each wheel as the build develops. Knowing my own weight distribution and that of the pack will allow me to determine the correct wheel weights as I go.



I am not as impressed with the front view as it looks too small and low with the little wheels and tall seating so that may have to change. I may not be vain about myself but my creations matter.;)


It is starting to look a bit like a Messerschmitt.


Cute but I want more of a...

look about it with a little...

and maybe some...

with a little...


I also found this which is quite cute.

Weigth distribution would work if that was a reverse trike though. But nice lines.
 
#28 · (Edited)
...With a real sized person in... Todd...
I think I might take offense to that statement! :p:D



...then the lovely sleek design that Todd came up with...
Gee, thanks - offense nullified. :) Yeah, it's tricky sometimes to get the proprotions right when real-world considerations are factored. It looked much longer in the first mock-up pics. One of the tricks in the sketch overlay I did was the front fenders are much higher than they need to be for adequate wheel travel. This was done to balance proportions with the much larger rear wheel. It still allowed a nice wedge shape though because of the size difference, and created large pontoon-style front fenders. Similarly, the motor would have been encapsulated in an oversized hump.

One of the challenges with electric, I discovered in designing the Inhaler, is the motor is really small by vehicle standards - even with small vehicles like we're working on. When you attempt to feature it in the overall design it makes it look tiny, or the rest of the vehicle shrunk-wrapped around it. Like it just ate a lemon! :D It takes some experimenting to find a nice compromise. I decided to magnify my motor's visual impact with the forced-air system to balance it with the body. At first I was trying to cut the body down to match it, but it killed the proportions of the T body - unless I were to build a 1/4-scale toy! :D



I played around a bit with the ground clearance and seating position.
I have raised the ground clearance to 6", mainly because I have a ready made platform that height for the motor to sit on, and I moved the seating position forward and reclined it a bit more.

...
I like this setup. It does, however, take a serious bite out of low and sleek. If my wrist and arm are okay I may be inclined to do some chicken scratching over that pic...
 
#27 · (Edited)
I played around a bit with the ground clearance and seating position.
I have raised the ground clearance to 6", mainly because I have a ready made platform that height for the motor to sit on, and I moved the seating position forward and reclined it a bit more.

(Holy cow, Batman! The invisibilty cloak works on the Batmobile!):D



That gave space to put the transfer box back.

The earlier issue of the transfer box was that the input was high up and the output low down. To solve that I tipped the box on its side so the mounts are now top and bottom. It means that the input is now at the lowest point and the output is back at wheel centre height.
The box is resting with a mount on the ground but that can be cut off and new mountings made up to suit.




As luck would have it the input is still on the centre line and running nicely under the seat position.:)
It also puts the range selector lever at the right hand side so I can put a short linkage to it (I'm getting good at them:p) to make it easy to reach.
 
#29 · (Edited)
I



As luck would have it the input is still on the centre line and running nicely under the seat position.:)
It also puts the range selector lever at the right hand side so I can put a short linkage to it (I'm getting good at them:p) to make it easy to reach.
Woody,

It's nice that it's all lining up, you deserve a few breaks.

But before you commit to this layout I would disassemble the transfer case and see just how you are going to lubricate some parts without drowning others and check the condition of the internal parts. When I built my first tractor I had to turn the differential upside down (another story). If I had only just turned it, it would have starved the pinion bearing. I ended up having to make a catch tray that carried splash to the bearing without overfilling the diff. and flooding the axle bearing and seals causing leaks.

I know I'm always the negitive one but better safe then sorry.:p

You and Todd seem to have a hand in each others pocket (across the pond is a long reach):D. The Idesas just jeep melding together.

Wonderful

I like what I'm seeing. Keep it up.

Jim
 
#30 ·
Take two.

I raised everything to match your component and seating layout, but tried to maintain some sexiness. With my previous post in mind, to feature the motor but not make the nose look like a duck's bill, I kept it level and rolled it down to the motor in front. As with the Inhaler, I used the height to make the design a little richer. I also swept the fenders in to the nose with a more convex curve, and some extra detailing (the line/ridge near the bottom). Pulling the nose down to the motor too fast makes it look like a certain sex toy! :eek::D Pulling the lines farther forward, and then diving them in towards the motor, gives a lot of surface to build character with. That's my story, and I'm sticking to it...
 

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#32 ·
I like that, Todd, :) I am going to have my work cut out to try and realise it.:D

I am begining to really get into this project. I might even be able to keep the weight low enough to make it work, never with lead for any real range but with lithium it is realisable and realistic.

I have been debating the practicalities of making a wood monocoque from 2mm birch ply glue laminations or staying conventional with a steel space frame or ladder chassis.
 
#34 ·
I like that, Todd, :) I am going to have my work cut out to try and realise it.:D

I am begining to really get into this project. I might even be able to keep the weight low enough to make it work, never with lead for any real range but with lithium it is realisable and realistic.

I have been debating the practicalities of making a wood monocoque from 2mm birch ply glue laminations or staying conventional with a steel space frame or ladder chassis.
I think a steel chassis with Woodsmith skin. It would capture the essence of Woody, with awesome steel structural fabrication, covered by organic, artistic, wood craftsmanship.

Piece a cake for the Woodster! :D
 
#39 · (Edited)
I added a bit of colour and shading. It needs to be a different colour but it shows up best like this.


Needs bigger front wheels I think.

I have been clearing out the unused files on my old desk top and de bugging it so that I can use the autocad package on it. It is giving me a chance to block out the drawings quickly and accurately while my drawing board is stored away and difficult to access.

Haven't got my head around the 3D of google sketch up yet, stuff I draw there doesn't look right and I am spending more time moving, adjusting, measuring and messing rather then drawing.

I am working on reclining the seat to near 45deg like on my KMX trike. It brings my head height down to around 42" and my eyeline to around 6' from the front of the trike. That is about the same as on the MR2.
 
#42 · (Edited)
I think I have found just the rear wheel I need.
http://cgi.ebay.co.uk/BMW-K75-100-R...em&pt=UK_Motorcycle_Parts&hash=item255c84586b
A complete set up from the BMW gearbox backwards. All I would need to do is to connect a motor to it and a suspension.:)

I think I will check my budget.

ETA:
Well, I bought it.

The gear ratios are a little low though. With the highest ratio final drive, 2.81:1, I can just get 69mph at 4000rpm. Best make sure that motor and propshafts are well balanced. :D
 
#44 ·
That's what I was thinking, Todd, simplifies everything.
I just need to find a way to make sure that I have enough rpm to get up to 70+mph, easy with a nice modern 9" series motor or an Agni but I'm not sure if my 12" motor will do it safely.
I could fit something to gear it up but it is more complication, weight and expense. Something like the old VW axle drop box from the camper van would do, compact and run backwards.

I am going to pick up the K100 unit today and hopefully get the brake caliper and maybe the clutch disc from it at the same time.

I was thinking last night, I could run a motor direct into the transmission and move the driving seat forward so my feet are ahead of the front axle. That would leave a space behind the seat and over the motor for luggage.
I also missed out on an auction for two 8" motors and fork lift controller They looked like wheel motors both with a disc brake on the tail shafts but I didn't figure on having a need for them. I could have run them siamiesed under the seat straight into the transmission.
Oh well.
 
#45 ·
Hi Woodsmith

I don't understand your rpm/speed calculation,

Wheel diameter (with tire) 23 inches- or there-about BMW 17 inch wheel + 6 inch tire
= approx 2m/ revolution
4000 rpm = 66 rps
2.8:1 drive = 66 x 2 divided by 2.81 = 47 m/sec
47 m/sec = 170 km/hr = 106 mph?
How do you get 69 mph
 
#46 · (Edited)
Hi Woodsmith

I don't understand your rpm/speed calculation,

Wheel diameter (with tire) 23 inches- or there-about BMW 17 inch wheel + 6 inch tire
[h1] approx 2m/ revolution
4000 rpm [/h1]
66 rps
2.8:1 drive = 66 x 2 divided by 2.81 = 47 m/sec
47 m/sec = 170 km/hr = 106 mph?
How do you get 69 mph
Gear box ratios.

The gears work out at:
1st---4.5:1
2nd---2.96:1
3rd---2.3:1
4th---1.88:1
5th---1.61:1

Then the bikes had final drive ratios of 2.81:1, 2.91: or 3.0:1

Not sure which I have yet.

This is it.




I also thought of putting the motor behind the seat, moving me to the front and all in the same wheel base and length, to direct couple it to the gear box. It would also give me luggage space over it.

(dodgy panoramic photo)
 
#47 ·
I will need to get a new tyre, this one has splits around the side walls. Also it doesn't look as nice as the Virago one. A big fat tyre is what is needed so I will need to see what the options are.
Pity the final drives are on different side or I would have had a look at swapping the two and having the Virago wheel.

Something else I could do is to make an adaptor plate to bolt on the hub and then have a stud pattern to match a wide wheel with a bigger tyre. That might just give me the extra diameter I would need to bring the 4000rpm speed up past 70mph.
There is a limit to how wide I could go though as the wheel is offset from the input shaft and that will only increase with width. To keep the wheel centred I will need to mount the motor off centre and that is a lot of 'off centre' weight with the 12".

Or I could just use a smaller motor with a higher rpm I suppose.:rolleyes:

Or off set with a step up gear train, chain or pulleys.
 
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