Three wheeler Cabin Scooter Design

[911hillclimber]

I was trying to think of such a shape that was 'one person wide' so to speak, and some fancy gliders are just that. Continuing the curves to the canting roof/door will be a prob, but could be in clear plastic.

For me, the biggest issue is reverse gear. For the vehicle to to 'real' for anyone it must have reverse. Bike engined cars have overcome this, but with a twist-n-go powertrain it gets far more difficult. This is the biggest hurdle technically. Could this be done via the front wheeels using a drive shaft to one wheel and an electric 12V motor (think disabled scooter technology?)
This would be great in aluminium tube construction and the twist throttle as a conventional accellerator pedal for public appeal and acceptance as opposed to a kit car.

Maybe when my Lola is all done I will get bored and think harder about getting a tube bender and some more welding wire! A front shunted big engined scooter would be cheap, and two matching/disc braked front wheels/hubs cheap too (I mean those feet-first scooter/bike machines with the long wheelbase, not a Vespa)

[stig mills]

Huge potential Italo with this one. Glider canopies tend to be placcy though and would only be allowed on a moped. Beyond that laminated glass is required. Its not cost prohibitive though to have one made, £1350 spent with pilkington and they made the tools for the Sonic7 screen. That included silk screen print for the black band and logo. Shame to have to limit the design to whats out there already. Curved glass with sides approaching parrallel like the "plane car" are to be avoided though but yours looks doable.

[911hillclimber]

The screen/canopy is really the stating point of such a project, the rest being easy to form (relativly) would have to come off the screen shape.
Still think the reverse gear will be tricky.

[Davi]

stig mills said:

Huge potential Italo with this one. Glider canopies tend to be placcy though and would only be allowed on a moped. Beyond that laminated glass is required. Its not cost prohibitive though to have one made, £1350 spent with pilkington and they made the tools for the Sonic7 screen. That included silk screen print for the black band and logo. Shame to have to limit the design to whats out there already. Curved glass with sides approaching parrallel like the "plane car" are to be avoided though but yours looks doable.

That's a hell of a lot less than they quoted me - was there a minimum order on those?

[fuoriserie]

I'm glad you all liked ....., in reference to the canopy, I was really thinking about a polycarbonate Glider canopy, than real glass due to cost reasons.

But if Stuart says that pricing could come down, or be lower than expected, if more units were manufactured , then I'm all for the glass canopy.

I agree on the scooter engine option, eventhough this idea started as the Mev Etrike rebody, and that is electric.

Reverse gear should be investigated, maybe a small electric motor ?

Cheers
Italo

Edited by fuoriserie on Wednesday 4th February 13:44

[mrmaggit]

Something like a 250 or 400 Suzuki Burgman as a base, perhaps?

It needs to have enough power to push it along 50mph dual carriageways at ease, against headwinds. I doubt 125cc would be powerful enough?

[stig mills]

Hi Davi, the tooling cost is not amortised by the quantity of screens made. The Sonic7 screen is not a difficult shape to form though. Anything with a depth of curve greater than 150mm starts to become more expensive as the tooling would then need to be counter balanced to hinge at a certain temp. The glass is curved up (not droop formed) in single sheets and is bonded together in pairs once shaped. You can imagine what happens if the curve is too strong, the sides are likely to fall in!
No reverse required for MSVA which covers "motor tricycles" not exceeding 1000kg unladen.
Plastic screen can be used on "3 wheeled moped" not exceeding 270kg unladen and not exceeding 4kw of power.
Thats about 5.5 hp. Weight of batteries are not included in the unladen weight which is quite handy!

[911hillclimber]

Sorry for the crappy sketch, but you could put a 'cubist' look to this:

[fuoriserie]

911hillclimber said:

Sorry for the crappy sketch, but you could put a 'cubist' look to this:

That is a good sketch.......

[fuoriserie]

Will post a few more sketches in the days to come.....

[Fat Richie]

mrmaggit said:

Something like a 250 or 400 Suzuki Burgman as a base, perhaps?

It needs to have enough power to push it along 50mph dual carriageways at ease, against headwinds. I doubt 125cc would be powerful enough?

Mrs FR has an Aprilia Habana Retro scooter, 125cc 4-stroke, quite capable of 75mph with 16-stone of fat boy sat atop.

[911hillclimber]

Where is the radiator for the engine on the scooter, at the front or under the 'floor'(I assume it is water cooled.
These details lend credability to this single seater as the occupant can enjoy warmth off the rad controlled simply by a vane. Screen de-misting is also easy.
With all that glass the thing will need serious cooling in the summer, but the Smart can have A/C too so that must be easy to plumb-in.

Really fancy doing this project when my racer is done this year.

I also have a 1968 Lambretta to restore...hence the scooter interest.

[Davi]

stig mills said:

Hi Davi, the tooling cost is not amortised by the quantity of screens made. The Sonic7 screen is not a difficult shape to form though. Anything with a depth of curve greater than 150mm starts to become more expensive as the tooling would then need to be counter balanced to hinge at a certain temp. The glass is curved up (not droop formed) in single sheets and is bonded together in pairs once shaped. You can imagine what happens if the curve is too strong, the sides are likely to fall in!

Cheers Stig, that would explain it - my requirements were for something along the lines of a stratos screen only wider.

[Chequred Demon]

I have thought of the problem of reverse on this kind of light weight/electric vehicle and came up with the simpe idea of a pair of folding pedals which turn the rear wheel by chain using a suitable reduction ratio. I realise this would not be suitable for everyone.

[mrmaggit]

How about a small motor (starter motor?) on an eccentric, operating onto the tyre?

[stig mills]

mrmaggit said:

How about a small motor (starter motor?) on an eccentric, operating onto the tyre?

You dont need a reverse gear for this type of vehicle. Please see my previous post.

[911hillclimber]

Agree you do not technically need a reverse, but if the idea was to be a commercial 'slant' then I think a smooth easy to use system would be needed. Imagine having to reverse up a slope and having to put a brake on, get out, release the brake and push and still be in control.

I'm sure in the 50's someone did a micro car where you stopped the 2 stroke engine and could restart it in reverse rotation to reverse it(!)

Anyone like to guess a gross weight for this kind of thing?
About 300Kg?

[mrmaggit]

stig mills said:

mrmaggit said:

How about a small motor (starter motor?) on an eccentric, operating onto the tyre?

You dont need a reverse gear for this type of vehicle. Please see my previous post.

We have a Grinnall Scorpion, which had Grinnalls own reverse. I removed it because we had to have a new gearbox shaft. I agree you don't NEED a reverse, and we manage quite happily without one, but it would be a massive boost for people not used to big bikes who park the wrong way round, and then can't shift the thing.

Imagine your mum going to the shops in one, putting the shopping in, and then having to get some people to help push her out of the parking space.

[911hillclimber]

Exactly, a commercial turn off.

I've been looking at this idea as a mass market, not a one-off build.
The Smart car is very close to the idea except for a few things (imho)

Too big: a single seater is a good idea, admittedly 2 seats adds versatility for the odd commutor occation.
Price: Far too expensive as a commute vehicle only.
Transmission: cronic gear change performance irritates.

I have friends with Smarts, a Brabbus and a racer and hired one for an Italian holiday. All are blighted by the gearchange, but the size and compactness were great, but for a going to work car, you can go smaller.

[stig mills]

I feel that cost will play an important roll here. What sort of figure would they sell for?
Obviously a reverse would be an advantage unless you remember to park facing up hill. A full screen will require a demister/wiper and a heater would be great. Locks on doors, wind up widows, decent interior trim to appeal to the shopper/commute market and we have a car with a price tag that could be more than an Aygo. Its only £35 to tax an Aygo too and thats coming down next year. Drive those 150cc scooter motors hard and they drink fuel and sound horrible. Sorry, that all sounds rather negative.
However make it electric and comparable vehicles are few and far between not to mention rather expensive. Swop 2 wires over for reverse but limit the luxuries and include weather protection and there maybe takers at the right price. But can a small vehicle be built by a small firm that would compete with the big boys or should the big boys be making one? I reckon they have all had their bean counters look at a single seat car and realised it doesnt cost much more to add significant value by adding an extra seat or 2 and a bespoke power plant.

Edited by stig mills on Monday 9th February 14:24