Bicycles

Front-wheel-drive KerVelo bike eliminates the chain

Front-wheel-drive KerVelo bike...
The KerVelo's pedals – and its 18-speed transmission – are in its front wheel
The KerVelo's pedals – and its 18-speed transmission – are in its front wheel
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The KerVelo's pedals – and its 18-speed transmission – are in its front wheel
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The KerVelo's pedals – and its 18-speed transmission – are in its front wheel
The KerVelo utilizes an existing Pinion transmission
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The KerVelo utilizes an existing Pinion transmission
According to Le Borgne, the KerVelo offers a seating position that combines the comfort of a fully-recumbent bike with the visibility of an upright
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According to Le Borgne, the KerVelo offers a seating position that combines the comfort of a fully-recumbent bike with the visibility of an upright
Le Borgne has already built two KerVelo prototypes, and is also interested in applying the design to a tricycle
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Le Borgne has already built two KerVelo prototypes, and is also interested in applying the design to a tricycle
View gallery - 4 images

Recumbent bicycles may offer a more comfortable riding position, but they typically also have pretty long chains. After all, power has to be transmitted from the pedals at the front to the drive wheel at the back. Norway-based inventor Marc Le Borgne, however, has created an alternative. His KerVelo recumbent has an 18-speed gearhub transmission built into the front wheel.

The KerVelo utilizes an existing Pinion sealed gearbox transmission. Although these are designed to be housed within the bottom bracket on upright bikes, Marc has put his in a custom aluminum shell that doubles as the front hub. It's sort of like a penny farthing, although because it's a multi-gear system, no huge front wheel is required in order to gain momentum – the pedals don't necessarily turn at the same rate as the wheel.

According to Le Borgne, the design offers a seating position that combines the comfort of a fully-recumbent bike with the visibility of an upright. And, of course, there's no long, greasy chain getting riders dirty, requiring maintenance, or decreasing pedalling efficiency once it starts to stretch out.

According to Le Borgne, the KerVelo offers a seating position that combines the comfort of a fully-recumbent bike with the visibility of an upright
According to Le Borgne, the KerVelo offers a seating position that combines the comfort of a fully-recumbent bike with the visibility of an upright

Needless to say, the big question is whether or not the front tire will rub against riders' legs in the turns. Marc tells us that at higher speeds, the turning radius will be wide enough that it won't be an issue. At lower speeds, he says, riders can just move their legs out of the way. It's probably something you'd have to try out first-hand to know for sure.

Le Borgne has already built two prototypes, and is also interested in applying the design to a tricycle. He's currently looking for commercial partners to manufacture the KerVelo. That name, by the way, is apparently derived from the Breton-language "ker" (house) and French "velo" (bicycle), as in "the best house to engineer the best bicycle" – although the Cervelo bicycle company would likely have something to say about that.

The more recent of the two prototypes can be seen in action, in the video below.

Source: KerVelo

View gallery - 4 images
16 comments
von Sea
it looks nice, but one of the reasons why chains replaced first bicycles' fixed pinions were the problems to fix the mechanism when it broke.
Shohreh
> He's currently looking for commercial partners to manufacture the KerVelo. That name, by the way, is apparently derived from the Breton-language "ker" (house) and French "velo" (bicycle), as in "the best house to engineer the best bicycle" Yes, "ker" means "house/home" in Breton. From his name, Marc Le Borgne is most likely from Brittany. Besides, the houses in the video look awfully from Brittany.
bhtooefr
There's gotta be a better way than using the Pinion (which isn't even a planetary hub), but I really like that bike's design overall for a city commuting bike. Not too long wheelbase, inherently low bottom bracket height, good height for visibility, lots of room for underslung luggage.
LakeeshaGobeatcha
Imagine it's a bit dicey starting off ... I find recumbants act that way, tho this one isn't extreme. The trike would be more to my liking ... then add a motorized rear wheel, and NOW you're talking! For us old guys, comfort, stability, and some help up the hills is all we ask.
Dziks
don't forget to raise your leg when turning or it will be sweeping the tire... That is why we use rear drive on fixed wheel, not the turning one.
Bob Stuart
I'm confident about tolerating the leg clearance in turning, but I'd not want to be always countering the effect of legs on the steering, and only the hands are available to resist the off-center pedal forces. It is rideable no-hands, but not at least effort.
wanderkip
In only 120 short years, we've come full circle to the Penny-Farthing!
Phoghat
the big question is whether or not the front tire will rub against riders' legs in the turns. no question at all
bergamot69
I wonder if this bike design would be better with a form of hub steering whereby a virtual wheel hub was further forward than the centre point of the gearbox (ie the centre of the pedal crank arms- the bottom bracket on a conventional bike), and the wheel would be spokeless yet connect with the drive chain via some kind of reduction gearing that also located the wheel, possibly also allowing for a degree of suspension movement also. That way, the wheel would be free to turn without fouling the rider's legs, or risking getting the feet in the spokes. I'm no physicist- I'm sure an engineer would be able to express what I am trying to say much more succinctly- I hope all this makes sense!
unklmurray
I want one of those wheels....just the wheel I don't need the rest of the bike.....