Direct drive recumbent.

[ayanmullick]

Does anyone know of a direct-drive recumbent ? Is there a way to convert an normal recumbent to one ?

This is what I could get from StackExchange.

http://bicycles.stackexchange.com/questions/21003/does-anyone-sell-a-direct-drive-recumbent-with-no-handlebars/21005?noredirect=1#comment37055_21005


?Re-posting it here as discussed with John ?Tolhurst

 

[Andrew 1973]

This...

 

[ayanmullick]

This has a non-geared hub.

This has a non-geared hub. You couldn't possibly make a Vandetta-like high-racer on similar principles.

 

[John Tolhurst]

The Garnet paper that claims

The Garnet paper that claims this is a good idea is based on a misunderstanding of bicycle ergonomics. The paper begins with the assumption that involvement of the upper body to control the transmission structure is dysfunctional. We know that is not the case - the whole body engages the frame, not just the legs. That means that the entire mathematical construct that is developed in the paper is irrelevant, seeking a solution to a problem that does not exist. At least, a problem that does not exist if you are looking to maximise performance. To my mind, effective conversion of effort into forward motion is the essence of a bicycle, no matter what kind you ride or who you are.

 

[ayanmullick]

But wouldn't a chainless

But wouldn't a chainless system be much cleaner, wire-free and easier to maintain.

 

[John Tolhurst]

Go ahead and make one if you

Go ahead and make one if you like the idea. To get you started the conversion kit includes brackets that allow you to put a drive wheel in the narrow front fork.

 

[richa]

Ayanmullick, 
The green

Ayanmullick,

The green machine is direct drive. Putting a transmission in the hub, as you are suggesting, makes it not direct drive.

So it seems to me that you're simply proposing replacing sprockets and a chain with gears. Which would indeed be much cleaner, wire-free and easier to maintain. And very much more complicated (internally) and expensive. Internal gear hubs are already expensive, and putting the pedal drive in the middle will likely add even more to the cost. So unless some kind of 3d printer technology gets invented that allows such a sophisticated transmission to be manufactured for cheap, I don't think we're going to see this in our lifetime.

But in the unlikely event we do, I want a penny farthing with this setup. The roadies will already be accustomed to recumbents (cruzbikes) passing them on the uphills but a penny farthing would be a whole different deal.

Rich

 

[Charles.Plager]

On BROL (but I couldn't find

On BROL (but I couldn't find it when I looked) somebody make a direct drive (the pedals were centered on the hub of the wheel) trike. I believe it was an 8 or 11 speed hub. So it's definitely possible.

I agree with John that this doesn't really make much sense. And I still think Andrew nailed it with his first post.

 

[ayanmullick]

Rear-drive recumbent bicycle

I am not looking to convert my bike though.

@Richa, I wrote to them to confirm if the NuVinci N360 could be made or modified to be directly pedal-driven. No response yet. Let's see. And the front wheel will have to be much bigger than the rear one anyway just so the rider's feet are near the front hub.

And it would have to be a rear-wheel drive like this.

 

[ayanmullick]

The recumbent mode is exactly

The recumbent mode is exactly what I am talking about. May be a little shorter. I hope they find an IGH to go with it.

 

[Eric Winn]

I grant you this looks cool

I grant you this looks cool but that Transform and Lock system looks huge and reminds me of a railroad car coupler - no offense intended. I also wonder about how it will behave under load and traversing rough surfaces.

Additionally some of those renderings of the different configurations beg to have a rider shown in place. Some of them don't look like a human would fit them correctly.

Hard to find a good website reference. It did win a design award. See toward the bottom of this page:

http://www.ifdesign.de/presse_detailseite_e.html?pmid=706

-Eric

 

[Gromit]

IGH - Schlumph Unicycle Drive

For an IGH maybe a Schlumph Unicycle Drive would work? Though I notice that the new owners of Schlumph, Haberstock Mobility, don't seem to list the Unicycle drive on their website.

 

[ayanmullick]

Just the recumbent mode.

IGH - SCHLUMPH offers a maximum overdrive ratio of 1.5. Highly inadequate for a recumbent. They will need one that allows a maximum overdrive ratio of 4 or 5. I can't find an IGH that has that; neither one that paddels can be attached to.

The transforming concept of the Mc2 might be overambitious. But I am just talking of the recumbent mode. Just that looks like a good clean design to me. But even a recumbent like that isn't available. May be becuse the unavailability of a suitable IGH.


I think a recumbent like that with a suitable IGH can become hugely popular. It'd be chainless, clean and low-maintinence.

 

[Gromit]

Pinion?

Maybe the folks at Pinion could be persuaded to build something? 18 gears - 636%

Off-topic. JT. Have you considered building a Pinion bottom bracket 18 speed gearbox into a Cruzbike?

Chain drive.

 

[Andrei Petrov]

Check out this internally-geared fwd mbb recumbent

The page has pictures of an internally-geared fwd mbb recumbent at the bottom. This company developed their own variator hub and claim that gear range of up to 4x is feasible. I saw a video of the bike in motion as well but can not find it at the moment.

http://www.profit2000.ru/variator/

Hope google translate does a reasonable job with this one.

UPD: a bit more info on the hub, the bike and a video are here:

http://www.velomobile.org/forum/viewtopic.php?f=1&t=5340

 

[Joakim Nilsson]

It's an absolute pleasure!

Lets see if someone still following this thread, and thanks Cruzbike for the opportunity to discuss!

The advantages that Ayan is talking about made me consider Garnets design together with the Pinion a couple of years ago. After about a years work the geared, MBB, crank-wheel concentric (and so on) bike was ready.

It is an incredible pleasure riding it, so ergonomically I dont find anything wrong in Garnets paper.

The handling is good, even in loe speed, once you get use to a MBB, guess it "feels" like a cruzbike in that respect. The upper body is indeed engaged when cycling! I expected the pedal force feedback to steering to be much worse than it is. In this respect I think Garnet has nailed the correct "angle" of the fron fork. I can ride it with one hand pedalling, even no hands when not applying much power.

The steering takes place about 30 cm behind the fork, but no wobbling in high speed observed. And talking high speeds - its a rocket, in 18th gear watch the swedish speed limits!
The lowest gear of practical use is something like 7, which I think is about one to one, one revolution of the wheel for one revolution of the cranks.

Traction: No problem (I expected some!) even uphill on gravel. Wheelbase is about 160 cm.

Frame rigidity: It's built of broken ice-hockey sticks (carbon!) so it was to soft to begin with. Now ok with a stiff carbon seat connected to the rear hub.

The people at Pinion have been asked about the "development" but they where to busy with introducing traditional use of the gearbox.

 

[Charles.Plager]

Wow!  That is fantastic!
I

Wow! That is fantastic!

I want more pictures! And videos! And more stats! (Weight, etc.)

(You should post over at BROL, too).

 

[Rampa]

Check out that bottom bracket headset!

Looks like it needs the offset of the crank-arms there to get the front hub in a usable location, and for wheel clearance. The riding position actually looks pretty good, but don't let that tire hit your leg. I like that on a Cruzbike your legs are above the wheel. Much easier on the calves!

Looks heavy, but might be a great commuter/winter bike.

 

[John Tolhurst]

Its interesting isn't it? I

Its interesting isn't it? I like how clean the structure is.

 

[Joakim Nilsson]

Thanks for your interest and

Thanks for your interest and positive comments! The Pinion gearbox weighs 2,7 kg (they have an interesting new "range" coming and I'm excited to see fewer gears and/or weight reduction. I think the front hub in total comes up to 5 kg, wheel total is maybe 7 kg, sorry for not having exact measurements at hand.
The bearing-holdings are made from high strength aluminium, whereas the casing (with spoke-holes on the mantle-surface) is an old kitchen pot!
In this design its good to have weight in the front - then the lenght of the recumbent can be shortened!

A good thing with the Pinion is that it has an "internal" freewheel. Actually I dont know why? They recommend for normal use to have freewheel at other end of the chain (in the back wheel hub).

One necessary item in the hub, (can be seen on the photo) is a "thin section" ball bearing, with inner diameter 17 cm and outer diameter 18 cm. Ordered from the US as it costs three times as much in Europe! If Pinion would someday become cooperative I think they could easily make this detail differently.
Total weight I estimate to about 15 kg.

The fact that the crank arms are lowered below the hips was an important POSITIVE feature for me. My feet tend to get numb on normal lowriders. It´s possible that this more upright riding position puts a little bit more strain on the hips though. I always use SPD, its more comfortable, and pulling the foot towards you feels natural, more so than on a normal bike. Both pushing and pulling the legs also stabilises the ride.

No clearance problems except when turning sharply in slow speed (as with all MBB:S?). I cant recall the tire having even touched my legs.

Some drawbacks are: weight, friction in the hub (maybe its the supersize bearing - although it was spinning quite smoothly on its own), price tag of the Pinion and the hazzle of mounting the Pinion in a wheel-hub.

There is a short film at instagram/hubcycle