tBear

Here lately I have been thinking on,building a recumbent bike. I am a good welder. I have a tubing bender and extra bike parts so why not. Never built one before,mostly I have been in the automotive field. But Seeing lots of pictures,I know I can. With that said. I have one question. Like most thats what brought me to this forum. Besides learning other stuff guys are doing. Being this is going to be a chain pedal driven bike. Has anyone ever seen,known of anyone,or have you ever put a small set of extra gears built into your bike acting like a single or more gear driven "block and tackle." Why because,it seems like we could run a higher gear ratio,with less efford. I think I have it designed in my mine,but if it will work that will be another thing. Building a recumbent with rear wheel drive,I will have the room. It just be designing,and adding more gears and chain. I have lots of diffrent bike parts diffrent brands. But most The gearing is going to be from a old Peugeot 12 speed touring bike. What you think guys ? Is it a crazy idea ? Think it will work ?, Any ideas ? Ever tryed it ?
It will be at least a 3 wheeler,or maybe a 4 wheeler. Another reason for this " Block & Tackle" in the future I may build a body for the trike. And even thought it will be out of light metal or fiberglass. It will be added weight to the bike. So it should ease the pedaling.
One said ad a gas or elect. motor. Yes I could, but then It would take away from being pedal powered. THANKS !

Asi

A close friend of mine made his recumbent out of an MTB frame (with 26" wheels)

The fork is a fixed MTB fork with disk mounting, spread to 135mm (he heated it with a propane torch, and after all welding was done he reheated it an oven to relieve the stress from spreading and welding). Also the front wheel is with disk brake as V's or calipers are not possible anymore if you need to weld on the crown of the fork.
Also welded a hanger on the fork dropout.

The frame was cut and bent (hot bend, not cold set) downward the downtube and seatstays, and re-welded to a much shorter seat-tube.

Parts attached to the fork comes of another bike frame cut to remain only with the seat-tube and chainstays attached to the BB shell. The rest was cut. The steer tube is attached by a clamp at the BB shell in a remainder of the downtube.


Hope it inspires you.

Dan Burkhart 

Here is the site you should check out for ideas and support from like minded people.
https://forum.atomiczombie.com/forum.php
I think what you are referring to as a block and tackle is what is commonly known as a mid drive, and it's done all the time on recumbent bikes and trikes. A multi speed freewheel with the pawls removed is the usual configuration.
My Quetzal recumbent used this design to make 105 speeds out of a 21 speed drive train.
I've since renovated the drive train, and the mid drive is now used as a speed step up and as a chain routing component.

dabac

A well designed 'bent has the possibility to be more aerodynamic than a regular bike, so, on the flat, a rider may expect to be somewhat faster on a 'bent than on a regular bike.
The span and range of gears is not a hindering factor for regular bikes. Ultimately limiting is aerodynamic drag and rider fitness - which goes for 'bents too.

'Bents frequently use a mid-drive, but that's usually mainly to route the chain efficiently. Small wheeled bents may also use them for a bit of extra gearing to compensate for wheel size.
Even on a 'bent it'll take a bit of doing to outride a regular road bike gearing, assuming you've compensated for wheel size.
For urban riding, there'll be external factors determining sensible speed anyhow, so adding an extreme range probably won't be much of an improvement.

Trikes can use a couple of crawler gears to deal with really steep climbs.
It's not that hard to add plenty of gears to a bike, just keep in mind that the number of possible combinations isn't the same as the number of usefully different gear ratios.
Whenever you're hooking one bike drive train to another you tend to end up with a lot of repeat ratios.

Bikes with fairings can be fast, real fast. Do a net search of "Varna Diablo" and you'll see just how. Not the most useful of machines though.
Fairings in general can, according to witness statements, fast become uncomfortably hot during summer season.

Kimmo

Recumbents are good for speed records because you can get them down to a really small frontal area, but you can't use your weight to make as much power as on an upright. Most prefer to make more power and use it less efficiently; I know I'm not too keen on pedalling when I'm lying down. Uprights also have other advantages.

Uh, hang on just a sec there, mate... your writing's a bit sketchy so I can't be sure, but are you saying what I think you're saying...?