Let's Talk Cyclecars

EVERYTHING goes better with wicker!

 

At that weight, you could say it's quicker with wicker...

 

That is a very interesting car. Too bad it didn't make it into production. Maybe FN wouldn't cooperate.

 

@edfueler Wicker!

 

https://theoldmotor.com/?p=183323
Have a nice Sunday

 

https://www.showroom.gunnandco.co.u...I6nJf8rr7eGAruiYFBmZvJxxnRqHhSEawrjf6MyksF8fM

 

I love it so much I have two copies!


Sent from my iPhone using H.A.M.B.

 

darmont factory image

 

WOW! Hot Rods & Cyclecars meet. Bob

 

IFAIK, the JAP motors the 500cc F3 guys used/use were the ones JAP made specifically for speedway motorbikes, open valvegear on a loose cinder racetrack wouldn't be a great idea.

However, from watching old film of speedway riders elbow to elbow whizzing round a racetrack, one foot skimming the cinders, all the bikes with near permanent opposite lock, none of it seems a great idea from the perspective of the riders' continuing health

 

It's like dirt track sprint cars on two wheels, if you're going straight you're doing something wrong.

 

A couple of nice cyclecar videos.

 

most excellent!

 

This car will be offered at auction later this month.https://www.prewarcar.com/322044-de...UMttyp4mKxN-QnZFoa762qzDeldeKMdlys_bM#group-1 .In the article it mentions that these cars were originally manufactured to use the surplus harley motorcycle engines.

 

1926 Salmson GP

 

Fantastic this videos!
Thank you

 

I know Dave( Bigcheese327 ) is kinda disappointed in the direction this thread has taken.Here's the kind of car he was trying to showcase with this thread when he started it.

 

I could argue that the 1914 Dudly Bug in Post #1, being a bona-fide cyclecar typical of American and European practice at the time, did presage the direction the thread took. Perhaps Dave was hoping for more speculation as to modern builds in the same broad idiom? That would certainly interest me. I have speculated about what might result from, say, a recent 600cc liquid-cooled motorcycle four in an Austin Seven chassis.

The perennial problem there is a reverse gear. Arranging one practically and affordably is an interesting problem, especially as I believe motorcycle-powered cars really need a wider ratio spread via an overdrive or two. Speculation about that could have added something to the thread?

 

On a philosophical point, it could be said that "small car" meant something different to the designers of the Edwardian cyclecars as for the the designers of, say, the Smart Fortwo. For the former, a small car is a light car; for the latter it is a short car. I don't know about anyone else, but to me the former approach feels a lot saner than the latter. In a sane world, a light car is something worth achieving; a short car only makes sense if the world we inhabit is so encumbered with imposed structural encrustations as to throw everything else out of whack. A world which needs to fill all the roadspace it has with an ever greater number of overweight cars is not a sane one.

A Smart Fortwo is less than 9' long and weighs anything from 1600lbs to 2000lbs. Compare this to the Jappic racer, such as @UKAde has been replicating, at about 12" long and 450lbs. Those figures also pretty much describe the definitive cyclecar, the Bedelia. In between we find for instance the original Fiat 500 (10'/1100lbs) and original Mini (10'/1400lbs) — both of which were already coming to be designed for space-efficiency rather than lightness.

I for one would love to see some investigation of extremely light cars out of a hot-rodder's mindset.

 

Dave expressed his disdain and disgust in post not long after the thread took off.

 

There is a youtube video where a company swapped an hyabusa engine into a Lotus Elise. they fabricated a gear box to get the power to the axles from the cycle transmission. The box also incorporated a reverse feature.

 

Here are a few threads:
https://www.jalopyjournal.com/forum/threads/ultralight-cars-how-low-can-you-go.246587/
https://www.jalopyjournal.com/forum/threads/lightweights-1500.660285/
https://www.jalopyjournal.com/forum/threads/thinking-small-–-baby-cars-with-motorcycle-engines.799543/

 

Any news as to winning bid?

 

It still seems like the Morgan three wheeler concept is one of the best lightweight ways to build a fun car with a motorcycle engine.

 

Here's a cmpany that makes some forward- reverse gearboxes for bike engines.
https://www.rpmgearboxes.com/

 

I've done a bit of research and crunched a number or two, and it confirms my suspicion that the ratios in a typical motorbike gearbox are really unsuitable for use in even a light car. Middleweight motorcycles typically have a ratio spread of about 2.2:1. A typical small modern car with a 5-speed manual might have a ratio spread of around 4.5:1. I'd submit that with the high torque-peak RPM and narrow power band which a motorcycle engine offers we'd need an even wider ratio spread if it's used in a light car.

I'm thinking of an auxiliary gearbox, mounted amidships between a motorcycle engine and gearbox turned 90° at the front and an axle or other final drive at the rear, providing three forward ranges and reverse. The first instinct is to go for an early 3-speed from a light car, but they tend to be wide-ratio, and there are fewer options to choose from than one might imagine. The Crosley 3-speed is really tiny, but its ratio spread if added to a motorcycle 'box would provide an overall ratio spread of about 7.5:1, which is perhaps too wide. The Ford 103E Anglia/Popular 3-speed is worse at almost 9:1. Lightweight 4-speeds from between c.1950 and c.1980 are much more common, especially as so many have been removed in favour of 5-speeds. With first gear removed they might provide far better options, if giving reverse ratios in granny territory. A sample suggests that overall ratio spreads of 4.5:1-5:1 are likely.

This approach also obviates the need for ridiculously short final drive ratios to accommodate the high-revving nature of a motorcycle engine. With a power peak at an engine speed about 50% higher than that of a conventional car engine, an overall first-gear ratio of about 5.5:1 is probably desirable, using a final-drive ratio within the conventional limits around 3.5:1. A motorbike first-gear ratio of say 2.67:1 times a low-range ratio of say 2.02:1 would give an overall first-gear ratio of 5.39:1.

Because the ratio intervals of the motorcycle gearbox would be far tighter than those of the auxiliary gearbox, you wouldn't drive this as a splitter arrangement. You'd use the auxiliary gearbox as a pair of overdrives above 6th. The sequential motorcycle 'box is likely to shift far more quickly and slickly than the H-gate auxiliary 'box, so you'd upshift through the former and then, once comfortably at speed, select higher ranges at relative leisure. When downshifting, however, you might stay in a high range and downshift through the motorcycle 'box.

 

I built a JZR 3 wheeler with a MotoGuzzi drive train and I find the gear ratios to be quite suitable. First gear is a bit tall and requires a little clutch slipping to get going but the rest works very well and the car will go up to 95 mph.
Having overdrive ratios isn't all that it seems to be unless you have enough HP and torque to push the car. Eventually wind resistance becomes and issue too.

 

It's about the spread, not the highest overall ratio. In your case, an extra gear would have allowed you a shorter first gear. Which Guzzi engine are you using? Lower-spec ones develop their peak power at a car-like 6000rpm, and have a relatively wide ratio spread.

The speculations which led to my previous post****umed stuff which develop peak torque at 11000rpm and peak power at 13000rpm, and rely on very low overall weight to allow a tight ratio spread: quite a different kettle of fish.

 

people loose sight of that issue when installing an overdrive box in place of their direct drive unit.not understanding that it also needs torque to move the vehicle along in overdrive.

 

A light but aerodynamically relatively dirty car should need about 20bhp to cruise at 60mph. For how much of the power curve does the engine make more than 20bhp?