Three wheeler Cabin Scooter Design

[Steffan]

In reply to KDIcarmaid may I first congratulate him on making the effort to move this topic forward.

Being very old and a complete Kit Car Nut since 1962 I have had a fairly extensive experience of actually driving three wheelers on the road.

I have owned and driven two Morgan three wheelers, three Berkeley's, several Bond Mincars. a Bond Bug, several Lomaxes, the Black Jack Avon, two Grinnall's, several scootercars by BMW, Isetta, three BSA Scouts two with V Twin JAP engines, one with a Ford sidevalve and others.

And two Peels (driven) and umpteen others like the Biota and Stimpson which I prefer to forget

Note: never a Reliant.

One turned over in front of me in 1963 and I never ever drove one in consequence. That incident established my fear of that layout.

Would that I had just ONE of them now!!! Apart from the Reliant.

The layout and low slung safe handling of the Lomax, Morgan, Black Jack, and similar layout cars makes for safe motoring.

The height of the scootacar and the height of the roll centre and tipping point is an inherent downside to that design. A serious problem.

The Berkeley and Morgan and Grinnall and Avon and Lomax can be slid around corners at pretty high speeds. The scootacar types cannot.

That is a major downside to me. I do not trust the cornering, stability and sliding ability.

The virtue of the Berkeley layout is a consequence of very low slung weight and the inherent stability of weight over the driving wheels. With two wheels at the front and a single trailing wheel st the rear.

It slides beautifully with no snapping no sudden break away, is very recoverable and never shows any sign of rolling.

I would happily race that layout on a track even in my dotage. I have rolled many racing cars, mainly sideways, sometimes end over end in my mad days and rolling a scootercar is not going to be fun.

So whilst I do appreciate the efforts to be constructive and move the topic forward IMO the only three wheeler that could actually be enjoyed with some vigour on the roads today is one based on the Berkeley, or more strictly the BSA and Morgan, layout.

Scootacars might work for a city car which never uses motorways of open roads. But on the open road? I do not think so.

The Morgan layout, reproduce by BSA, Berkeley and others is inherently more stable. In an emergency infinitely safer.

My observations are based on my experience with these unusual cars.

I admire you efforts to move the progress on.

We need enthusiasts to experiment and suggest possibilities.

But I am not sure about scootercars in general use.

[Davi]

To summarise my view (without such extensive experience!!!) Steffan said it all!

My one issue with something like the Berkeley is crash strength. I know the best idea is not to get in a crash in the first place but I'm getting too old in my sensible age. Or something like that.

Personally I'd like to see something on the berkeley design but built ala F1 tubs today. Okay not literally, but utilising the same principles so that you'd stand a chance of walking away from hitting an errant leaf.

[skwdenyer]

The Morgan-pattern trike is pretty safe, so long as all is well. But, as with any 3-wheeler, the lack of redundancy is a problem. Back in the day, many Morgan drivers were injured, and many more Morgans perished, due to slow punctures. Due to the inherent stability, the driver didn't notice a slow leak until it reached the point at which the rear tyre could offer no more lateral grip, resulting in an almost-uncontrollable drift, a hard connection with a kerb and, more often than not, a rollover event. Often this was precipitated by a working-loose of the wheel's spokes.

Modern wheels and tyres help a great deal, of course.

[Davi]

I was thinking more from the point of impact protection from other morons on the road! I've been driven into 3 times whilst sat stationary in traffic - I doubt I'd still be here if I'd been in a morganesque!

[Steffan]

Davi said:

I was thinking more from the point of impact protection from other morons on the road! I've been driven into 3 times whilst sat stationary in traffic - I doubt I'd still be here if I'd been in a morganesque!

That is a legitimate concern. I have never rolled a three wheeler. I do not want to.

I have had a Morgan catch fire with a leaking tank feeding by gravity an burst into flames. That was fun. I lived to tell the tale so did the Morgan. Slewed to a halt hopped out and fortunately there was a water container in the back I was going camping. Pure luck. Car was singed but it was a wreck anyway. I got it on the road, wanted a change... cest la vie.

There is a dichotomy in the need for low weight and the need for strength. Side impact in particular on a Berkeley, Morgan, or any other three wheeler for that matter.

Frontal impact could be assisted by the mass of the engine, subframe, firewall etc. Rear impact by the boot and rear frame.

Side impact could be very serious.

Just fibreglass and bracing struts on the Berkeley. Insufficient. Arguably unsafe.

Roll over protection is possible though few cars actually have this.

This is not an easy conundrum.

Which may explain the absence of a modern example.

[skwdenyer]

Steffan said:

There is a dichotomy in the need for low weight and the need for strength. Side impact in particular on a Berkeley, Morgan, or any other three wheeler for that matter.

Frontal impact could be assisted by the mass of the engine, subframe, firewall etc.

Modern materials, or modern techniques with older materials (variable temper on extruded aluminium 'crush' tubes, for instance) can revolutionise frontal impact management, even on something as short as one of these.

Steffan said:

Rear impact by the boot and rear frame.

Hmm, only if you stick with the trad wire wheel and plan for deformation of said wheel against a hard bulkhead placed between wheel and driver. If you put a modern wheel/tyre combination on the end of a stiff trailing arm, those will be essentially non-deformable in a rear impact event.

Steffan said:

Side impact could be very serious.

Just fibreglass and bracing struts on the Berkeley. Insufficient. Arguably unsafe.

The situation isn't noticeably worse than, say, a Caterfield, save for the absence of a rear wheel to take some of the loads. There are essentially 2 problems:

1. Cockpit width. If you must insist upon sitting in a cockpit so narrow that your arm is essentially outside of the body then, sadly, there is little that can be done short of some sort of external airbag.

2. Tub width. Even if the tub is made wide enough to fully enclose the driver, aesthetics and - to a lesser extent - dynamics dictate that a wide 'sidepod' isn't all that desirable.

If the styling is all-new then this needn't be a problem; essentially ape what is done in F1 using side impact structures mounted outside of the tub. Making a Morgan-a-like with decent side impact protection is difficult.

Is it 'arguably unsafe?' Hardly; it is, however, what it is, which is not a modern structure.

Steffan said:

Roll over protection is possible though few cars actually have this.

Agreed; either fixed or Mercedes-like pop-up roll hoops are quite possible if demand exist.

Steffan said:

This is not an easy conundrum.

It seldom is in vehicle design if the aim is to fit within an existing envelope. If one can innovate in layout - such as in the unrelated Murray T25 - then forces can be managed much more effectively.

Steffan said:

Which may explain the absence of a modern example.

That might offer one reason for the lack, certainly. The fact that, as a vehicle to do more than convey 1/2 people down a country road, the pattern is deeply flawed might be another limit upon demand

[KDIcarmad]

Steffan said:

The layout and low slung safe handling of the Lomax, Morgan, Black Jack, and similar layout cars makes for safe motoring.

The height of the scootacar and the height of the roll centre and tipping point is an inherent downside to that design. A serious problem.

Yes the Scootacar dose at first look height. In fact most the weight is low down below the window's bottom edge, the engine is behind and below the rear seats. (If you cut about where the window start and lift the top off, you would find all the weight is in that lower half). This give it a lower centre of gravity than it looks. I will be honest here I have not driven one and only seen two scootacars (one a MK1), so am going on what I have read.

You have owned or driver a lot of interesting cars. I have been a passenger in a Morgan, they are incredibly quick. Out of interest do you know the US Trihawk. A car of similar design that in the 1980's out handle many supercars in magazine test. It is claim to have pulled 1g corning and on the skid pad to have been better only be a few mid-engines.

I still like the idea of MK4 scootacar.

[cazzer]

Steffan said:

KDIcarmad said:

qdos said:

Just to resurrect this thread again and the topic of three wheelers. It seems the Delta is getting noticed more now that Nissan are involved with it too

OK it's not a 3 wheeler as such and barely a scooter either.

http://www.pistonheads.com/news/default.asp?storyI...

This is not going to restart this. The Deltawing as a far moved from this as the moon is from the Earth.



Now this could,...
Do you want a car like this on you driveway? YES! YES! YES!
This is the T60 Berkeley. A 328cc powered 60's sportscar, a cousin to Berkeley's 4 wheeled cars. A very good seller. An update of these with modern styling and a top speed over 80 (needs to hold 70 mph on a motorway) would be very popular. So do you want one now!

Edited by KDIcarmad on Wednesday 14th March 16:27

YES I WOULD. I have been looking for a revitalised Berkeley for years.

NOT with a Mini engine ONLY with a motorcycle engine up front!

The A series is too heavy with all the associated subframes drivetrain etc.

There have been attempts to produce new moulds.

I believe the Berkeley club have the originals.

But no real progress so far as I am aware.

I would buy and build one tomorrow. I cannot find such a project.

http://www.ebay.co.uk/itm/Berkeley-T60-/2709379981...

No need for copious thanks

[Steffan]

Cazzer: Thank you I am onto it now.

[cazzer]

Its also not that far from me if you want me to go have a look for you.

[Steffan]

A very helpful offer: I am in communication with the vendor I will keep your offer in mind. I am due back in Brum shortly and may see my son in law in Leeds so with luck I will be able to look myself.

Thank you once again.

Another one has turned up but it is an uncompleted kit. Still I am onto that as well.

See http://www.ebay.co.uk/itm/Berkeley-Mini-Cobra-Body...

[FlossyThePig]

One of my RSS feeds delivered this link today. I'm sure the BugE has been mentioned on this thread.

[KDIcarmad]

Above is the Moonbeam, a US home built car that I think is what this topic is about. Below this a site about this car and how to build one. I know all this has already been posted, but think about this a lot of new people don't go back and read all the old posting. (Which is very bad!)
http://mysite.verizon.net/vze6omtd/jorysquibb/id20...

For use in the UK I feel this is to slow, you need 80mph for motorway use and a good 45-50 on most fast A/B roads. Clearly at speeds like these you need stronger crash protection than this offers. As the cost of fuel shoots up a cheap to run car like this start to make more and more sense. Has any one build one in the UK?

[Davi]

KDIcarmad said:

Above is the Moonbeam, a US home built car that I think is what this topic is about. Below this a site about this car and how to build one. I know all this has already been posted, but think about this a lot of new people don't go back and read all the old posting. (Which is very bad!)
http://mysite.verizon.net/vze6omtd/jorysquibb/id20...

For use in the UK I feel this is to slow, you need 80mph for motorway use and a good 45-50 on most fast A/B roads. Clearly at speeds like these you need stronger crash protection than this offers. As the cost of fuel shoots up a cheap to run car like this start to make more and more sense. Has any one build one in the UK?

Frankly I'd want more crash protection than that offers just to use it on a cycle path. I think with todays material availability, coupled with the weight and size of modern vehicles, you just don't want to be inside something that would fold like a paper cup if you breathed on it the wrong way.

[qdos]

Davi said:

Frankly I'd want more crash protection than that offers just to use it on a cycle path. I think with todays material availability, coupled with the weight and size of modern vehicles, you just don't want to be inside something that would fold like a paper cup if you breathed on it the wrong way.

And yet many happily belt around in Seven at well over the legal limit without even a thought to it. If you go down the 'Must be big and strong' route we all wind up driving tanks. The truth of the matter is that we can not afford to be going this 'Big and Strong' route and it's actually just marketing hype any way. When did you last total your self when walking down the High Street or at worst ran down it? People have been crashing into one another for hundreds of thousands of years. It's when we get into big heavy steel boxes that the problems really begin.

Look at it this way... Put your children in the school playground and then imagine little Jimmy turns up on it in a Range Rover. Does this mean everyone has to go and get a Range Rover or Volvo to let their kid go on the playground? Now what do think is safe? The reality is that it's how you drive which makes you safe or not.

[Davi]

qdos said:

And yet many happily belt around in Seven at well over the legal limit without even a thought to it. If you go down the 'Must be big and strong' route we all wind up driving tanks. The truth of the matter is that we can not afford to be going this 'Big and Strong' route and it's actually just marketing hype any way. When did you last total your self when walking down the High Street or at worst ran down it? People have been crashing into one another for hundreds of thousands of years. It's when we get into big heavy steel boxes that the problems really begin.

Look at it this way... Put your children in the school playground and then imagine little Jimmy turns up on it in a Range Rover. Does this mean everyone has to go and get a Range Rover or Volvo to let their kid go on the playground? Now what do think is safe? The reality is that it's how you drive which makes you safe or not.

Others may, I don't, in fact impact protection is the key reason I've not had a sevenesque. I did not, however, say anything about big - only strong. A Smart car weighs ~ 700 kg but have a look at it's impact protection. An F1 car is 640kg but look at the driver cell strength on that. I'm talking about making use of the technology and materials available, not just bolting an extra few tons of steel together.

As to how you drive - I do not think I'd have survived either of my last two accidents in that thing above. Both accidents occurred while I was sat stationary in traffic jams and was hit from behind. The limit to what you can do to prevent an accident is governed by just how ste the other drivers around you are.

[KDIcarmad]

Davi said:

qdos said:

And yet many happily belt around in Seven at well over the legal limit without even a thought to it. If you go down the 'Must be big and strong' route we all wind up driving tanks. The truth of the matter is that we can not afford to be going this 'Big and Strong' route and it's actually just marketing hype any way. When did you last total your self when walking down the High Street or at worst ran down it? People have been crashing into one another for hundreds of thousands of years. It's when we get into big heavy steel boxes that the problems really begin.

Look at it this way... Put your children in the school playground and then imagine little Jimmy turns up on it in a Range Rover. Does this mean everyone has to go and get a Range Rover or Volvo to let their kid go on the playground? Now what do think is safe? The reality is that it's how you drive which makes you safe or not.

Others may, I don't, in fact impact protection is the key reason I've not had a sevenesque. I did not, however, say anything about big - only strong. A Smart car weighs ~ 700 kg but have a look at it's impact protection. An F1 car is 640kg but look at the driver cell strength on that. I'm talking about making use of the technology and materials available, not just bolting an extra few tons of steel together.

As to how you drive - I do not think I'd have survived either of my last two accidents in that thing above. Both accidents occurred while I was sat stationary in traffic jams and was hit from behind. The limit to what you can do to prevent an accident is governed by just how ste the other drivers around you are.

I agree with you both. A lot of bad drivers create problems for the rest of us. A small car like the Moonbeam will alway lose in a crash, as will any motorbike. Think of a Moonbeam as a motorbike and you understand the risk.

Yes modren design and materials can improve this designs crash protection. I do wonder if in the US with its 55mph limit they think about crash protection in the way we do?



This is the Roopod. Does this look safer? It still small and light.

[qdos]

KDIcarmad said:

Think of a Moonbeam as a motorbike and you understand the risk.

Exactly. The title to this thread "Three wheeler Cabin Scooter Design" says it quite clearly. All too often people keep harping on about bigger, faster, more accommodation, safer etc etc.

If folk want a car then go and look at a car and simply stop looking at scooters. If we all rode around in scooters though, particularly these sorts then the roads would be far safer places. Would Davi have had as much damage had he been hit from behind twice by a scooter each time?

Edited by qdos on Friday 30th March 21:10

[KDIcarmad]

This is the OZY by Charley Arrieta. Yes it was inspired by the Moonbeam and I love it! Sadly English is Charley second or third language so if you look this up please understand that. Still I wish I could build a car as good! Maybe one day...

[KDIcarmad]

I have been debating what a scooter car is a friend. What defines a car as a Scooter car design?

I added to this question what stops it being a Cyclecar?

It has to be more than the size of engine, as the Smart cars would a scooter design. Clearly a Smart is a micro car. After a hour we came up with this....

A scooter car must use an engine under 650cc (over this it's a Cyclecar/micro).
It should use a scooter gearbox (CVT gearbox).
It must use motorcycle wheels and tyres. (Or go-kart wheels and tyre).
It should be a simple design.
Easy to drive, like a scooter

We had a lot trouble agreeing on the max engine size, instead of length or weight. Gearbox was a given for me, as was easy to drive. Wheels were something I felt was a little limiting, but the use of Go-Kart wheels seems a good idea. Tell me what you all think.

Reading these they look like the first line of the design note for a race series.