Let's Talk Cyclecars

Here is what the swing arm rear end can do. With a locking diff. you would be in real trouble.

 

The epitome of what a car should look like IMHO.
What is the engine in the GN Parker? Looks similar to OX5 valve gear, but has to be aircooled.

Herb

 

Herb ,it is a Cirrus aircraft engine.

 

Isetta

 

It shows why that era is called "Vintage".

 

marc pic...

 

V8 JAP engine in museum mode.Notice the cutaway cylinder...and the cutaway cylinder in the engine behind it.GCL pic...

 

Hello SR100 and Ned, ​

Thank you on information and nice photos of NAMI-1: mistery is solved.
For most of us, USSR and before that old-Russian history of motorisation is quite gray zone, with a lot of interesiting expamples and mechanical solutions...

Ciao, Zoran​

 

1921 Aerocar cyclecar.The Aero Car was the size of a Cyclecar. This two passenger Aero Car weigh in at 150 pounds, wheel base of 60 inch, tread of 30 inches and sold for only $160.00. This automobile was really driven by propeller. The motor could be started from the seat, one lever controlled the engine while a foot lever controlled the brake.
Aero Car
The Sheldon F. Reese Co.
Huron, SD
1921
The thrills of an Airplane, the safety of an automobile and the economy of a motorcycle. All were combined in a propeller driven American Automobile designed by Sheldon F. Reese of Huron, SD.

The Aero Car was capable of 60 MPH and equipped with a twin cylinder engine of six horsepower. Production was unlikely but a protype was built. Image by Marc,text by R.A...

 

Carden Monocar...marc pic...

 

Messershcmitt. I don't think she's going to go for a ride with him.

 

Come to think of it, there were in the Vintage era a number of cars which shared this unusual combination of solid front axle and IRS. Steyr had a few, too, like the Type XII which I believe was the definitive Vienna taxi for many years:



Also available with commercial bodywork:


But we digress, as these are way beyond cyclecar scale

 

... so, just to find similar, but smaller?
Zoran

 

Steer it with throttle, the finish line is in sight.

 

Geo Hamm

 

Amilcar C6,1938 Bol d'Or,driver Georges Grinard. Marc pic...

 

Hello Fred,​

I had nice chance to drive both Herald and Spitfire (for short time), some 3 decades ago... Just to say that in my childhood and early youth in Belgrade, we consider any British car as sporting auto, and anything built by Triumph as true sport cars! So, even being something older, I used to drive both of them quite fast across and around city. They were quite lively at rear around corners and sharp curves, especially on wavy surface. I didn't have too much problems having a lot of experience with swing-axle vehicles: Zastava 750 (FIAT 600d made in Serbia under license) and its faster derivatives , than SKODA 1000mb, VW-beetle 1200, RENAULT 8/10 and NSU 120c. All of them had rear engine and rear power, but something modified according to simple swing-axle suspension. NSU was the best of them (but quite dangerous at high speeds – light front end) and next to it was RENAULT, the worst was SKODA. Never could know how to pass curves with it: beside bad rear suspension, front wasn't better including heavy and imprecise steering...

However, all of them were quite fun to drive, but only when I know and respect limits of autos, road and myself...

I couldn't be sure for differential-less power: never had auto with blocked or limited differential. Maybe lack of differential shouldn't be too bad for NAMI-1: good power on snow and mud, and under-steer at curves that should compensate regular over-steer (???) and keep power at outside wheel while inside one is over ground in the air. Just theory: maybe all that should lead to disaster during nervous and fast driving...

Ciao, Zoran​

P.S.: Our racers from National class (sixties and seventies), solved problems (almost) with swing-axles of Zastava 750, when pressed rear coil-springs so much that run almost without any suspension's work, getting "X" layout of wheels instead of "O"...

 

Hello Ned,​

Theoretically, such different layouts for front and rear suspension should lead to bad road-holding and disasters, but... Probably designers (and industrialists) tried to solve a few problems on the simplest and most practical way. Over (mostly) bad macadam roads of period, they need independent and flexible suspension, so they choose swing-axles for rear, where are passengers and freight. At front they kept solid axles as the most simple type and one that would keep good steering geometry in all circumstances. It would keep wheels in steady (almost) vertical position to ground? Beside, sold axle ares strong and in that period all autos got front brakes... And, they are CHEAPER!)

Swing-axles at front could be used, but could give nervous suspension and steering over bad roads and fast driving trough curves?

Ciao, Zoran​

 

BSA

 

bizarre 3 wheeler

 

Tonight this thread reached a milestone....

One MILLION views
6,236 posts
208 pages
just about seven years and running....

 

Hi Zoran

I suspect that ride quality was the main motivation here. The swing-axles allowed the designer to add the relatively heavy final drive to the sprung mass, which made for a lower resonant frequency for any given spring rate. Given the limited grip afforded by the tyres of the day the favourable camber recovery characteristics of the swing-axles probably outweighed the jacking tendency: the car would likely skid before it found itself in the sort of situation you showed in your previous post. Moreover, because Hans Ledwinka's differential design had the axles swinging about the pinion axis it placed the roll centre at hub level, i.e. roughly the same height as a conventional Hotchkiss drive's. Where U-joints or CV joints are used the roll centre would be a bit higher and exascerbate the jacking tendency.

The camber recovery characteristics would also have offset the spring-base considerations: the reason why the focus was on IFS elsewhere. The effective spring base of an independent suspension is necessarily equal to the track, unless modified by use of an anti-roll bar (which is ordinarily undamped despite often representing a wheel rate greater than the main springing - the reason I dislike anti-roll bars). Usually the spring base of a solid axle is less than the track, though it is perhaps more accurate to say that it is not necessarily equal to the track. I have been able to devise methods of locating a solid axle which give an effective spring base greater than the track.

The spring-base issue dominated early suspension development. Because front spring bases tended to be narrower than rear spring bases, there was generally more roll stiffness at the rear for any given spring rate. This created a general oversteering tendency, so much so that bad handling must have been synonymous with oversteer in the minds of early suspension innovators. The appeal of IFS was a front effective spring base equal to the track and less camber recovery than the rear suspension, i.e. that which makes for understeer. I do not think the theory of tyre loading v. slip angles was quite understood, though. I do not think it was articulated by 1930; it certainly was by 1950. Resonant frequency theory was well-known, though: Dr. Lanchester had used it in a suspension design before 1900.

 

Any IDeas on the convertible and bizarre 3-wheelers?

 

The green one is a Berkeley: 2-stroke motorbike engine and FWD, made by a manufacturer of caravans (i.e. trailers).