Recumbent - University Recumbent Project!

Hi guys, my name is Tremayne Wallis. I am currently a student in Brighton, England studying Design Technology. I am now in my second year and have just started a new project, along with four other guys which consists of designing, developing and building a recumbent bike. We are hoping to make a recumbent that stands out, but the main aim is to optimise everyday userbility. We are currently going through extensive research resources, so therefore we are in the early stages of design and development.

In order to help us with the development of the bike i would like to get some feedback from as many people as possible who are currently riding a Recumbent bike. The most important information i need is any ideas on improvements, areas that always bug you or any innovative ideas you may have. We would like to know what you use your bike for whether it be riding to work or for pleasure, even off roading and the bike you ride. Please dont hold back on anything, all feedback recieved will be greatly appreciated as we are taking this quite seriously. If you have any queries please put it up on the forum or feel free to e-mail me on ttw0416@hotmail.com.

Figure out a way to make a recumbent all-weather, but not necessarily by fully enclosing it in fiberglass. One weakness is that they aren't quite as good as a regular bike in rain/snow, and certainly not as good as a car.

I'd want a bent that is easily portable so I don't have to lock it outside, and light so it's not a pain to carry around. OSS or USS doesn't matter to me. I think the Brompton recumbent conversion was the ideal design, but many said it was heavy to carry, and cumbersome in it's conversion design. At one point, someone made a conversion for the Birdy frame as well.

I ride a RANS Rocket and mainly use it to pedal the kids around in their trailer; much more comfortable that way. But they are getting older, and I would like to take them to the library, but don't want to lock my bike outside. My ultimate desire would be that I would be able to ride to the library, take the kids out of the trailer, fold the bike, stuff the bike into the trailer for storage, and stroll the trailer around with us while we're all in the library. So far, I can only conceive of doing this on my Brompton, but a bent would be nice.

Oh, and while you're at it: a folding tandem recumbent would be nice as well.

Just my two cents worth. I think you need to decide on a TYPE of riding you want to adress, then work from there. Just a blanket (we want to design a bent, can you tell me what is wrong with yours) is way to general. I mean I would like something that is acomfortable as my LWB, can hold a 300 lb engine, is good at the 6-8 MPH speeds with paved and path tires. Could not care less about putting it on a bus, or lifting it. But as you can see from the other posts, their needs and mine would result in completly different bents. Choose a niche, and design for that.

Hi guys, my name is Tremayne Wallis. I am currently a student in Brighton, England studying Design Technology. I am now in my second year and have just started a new project, along with four other guys which consists of designing, developing and building a recumbent bike. We are hoping to make a recumbent that stands out, but the main aim is to optimise everyday userbility.

Build a CLONE of one of these
that can be purchased for $400 - $1,000.
http://www.bacchettabikes.com/b-corsa.htm
I want to buy one for that! I can be your
first customer. :O)

Ned Goudy
Glendora, CA USA

you are correct in saying that everybody has different needs. This is a common factor in all customers for any type of bike whether it be downhill or racing. I ride downhill, jump for example; my friend prefers 24 inch wheels where as i prefer 26 inch. However, what i am trying to achieve is to find a generic problem with existing recumbents, not to put every problem right, other wise i would end up with a rediculous recumbent that is trying to fit every market.

Thanks for your input, all is helpful.

Hi there, myself and my design team are looking at targeting the commuter market so your infrmation on the bike being disadvantaged in the rain/snw is quite interesting. However could you tell me in which way, is it less unstable compared to a upright bike due to tyres, riding postion, or do you get more wet?

There is one measure of security that I would take if I were to build a lowracer recumbent. I would fasten a mast on the frame on top of which there would be no flag but twinkling lights, a white one for the traffic in front of you and a red light for the traffic behind.

I ride one of my recumbents in the winter without any problem. As I rode an upright before even in the winter I can assure you that a recumbent seems to be a better choise even in the winter owing to a better stability and safer conditions in case of a fall.

I suppose one thing that people complain about (though its validity is questioned by seasoned recumbentists) is its ability to climb hills as fast as a DF bike.

Build a recumbent that climbs as fast as a DF, and you'll be a hero!

Hi there, myself and my design team are looking at targeting the commuter market so your infrmation on the bike being disadvantaged in the rain/snw is quite interesting. However could you tell me in which way, is it less unstable compared to a upright bike due to tyres, riding postion, or do you get more wet?

The main disadvantage of bents vs. regular bike, imho, is that you can't throw your weight around, i.e. shift your center of gravity left/right and forward/backward, or lift your weight off the bike temporarily to pass obstacles. I would not ride a bent in slippery conditions (snow) because of that.

If you target the commuter market, I presume you want riders to be at ease on your bent in the city. Here are some design elements I'd want on such a commuter bent for myself:

- Short wheelbase format with a pedal boom that folds up. SWB bents are nippier, and the folding pedal boom would make it ideal to take on a train or attach it behind a car, because it would then become the same length as an upright bike.

- Steel frame with nice powder coating. Forget alu, it's expensive to work with, can't take real abuse, and doesn't age well. A properly rust-proofed steel frame is bomb-proof, cheaper and durable.

- US-style seat (i.e. with a frame and a mesh), but with a European-style back curve and more laid back than a traditional 2-part seat. What I mean is, the euro seat is much better than 2-part seats imho, but the mesh is good enough to ride directly on (no seat padding required) and can take the rain without leaving your butt all wet when you go back home.

- over-the-seat steering: it's narrower than under-the-seat steering, so it's more agile between cars. It also has more turning radius, is more intuitive for beginners and accepts componentry mounted the "right" way (no inverted brake levers and shifters).

- 26" tires, with the seat designed so that everybody can ride the bike. 26" bents are usually quite high, and sometimes too high for practicality. If you can find a way to seat the rider low on a 26" bike, you have a safe, comfy, ubiquitous bike that you can find parts for at any bike shop.

- Suspension front and rear: it's essential in the city on a bike you can't lift your weight off of.

- Mudguards that wrap very low to the ground at the back of the rear wheel. Yes, I know it's silly, but that's the thing that always bugs me on any new bike I get.

- Re drivetrain: derailleurs are a cheap way to provide a wide gearing, but they need maintenance. On a commuter, I'd want a geared hub, but it's more expensive. I think a Nexus-8 hub would be a minimum on a bent (remember, you can't honk on a bent, you have to spin). A Rohloff Speedhub with 14 gears would be ideal, but it would make for a very expensive commuter, unless of course potential customers managed to realize the savings in the long term. For a reasonably-priced commuter, I'd personally like a Nexus.

- A full chaincase, or something equivalent for a bent, which has a long chain. Easy to design with a geared hub, hard with derailleurs. Cleaning the chain is always a chore, but it's especially annoying to do on a utility bike, at least for me.

- Plenty of rack space: commuters always have something to carry, be it the laptop, backpack or briefcase. It'd be nice to have a new bike equipped with enough rack space to tackle real-world usage for once.

- Lights. Please! a bike that comes with lights, that I don't need to add lights to. Multi-led lights, front and rear, are nice and efficient.

- Since you're still in the design phase, perhaps you could design an in-frame python-lock, that is, a strong thick cable that neatly coils inside the frame for stowing, and can be pulled out to attach the bike to a post. I've seen scooters equipped with that gadget, it looks very neat, and you never forget your lock with that.

Well that's it. I hope you find some usable ideas in my wishlist. If you ever manage to do all that for under 1000 EUR, give me a holler, you've got yourself a customer :)

As an engineer for most of my life I have cases there are trade offs between desirable aspects of a design. If you make one thing better something else gets worse. The best design is one optimized for a particular persons tastes. With that said, I have one suggestion.

Long wheelbases suck because the front wheel is so lightly loaded that it slips out in light gravel, wet surfaces, ... The rear wheel suffers because it supports most of the bikers weight. Short wheelbases suck because the steering is too responsive. The wheel base is so short that it is on the fringe of being unstable and inexperienced riders can loose control if they sneeze to hard. There is a fix.

Why does the seat have to be so close to the rear wheel? If the seat is moved forward, the weight distribution on a LWB becomes better. The bad thing is that the already long wheel base becomes longer. On a SWB, if you move the seat away from the rear wheel by lengthening the wheel base, it will make the bike easier to steer. You can make the wheel base comparable to most DF frames. The penalty of lengthening the wheel base is higher stresses for a given tube size and more weight. With traditional heavy weigh steel tubing, the extra weight may not be worth the improved stability. With modern materials, the extra length would add minimal weight and could make recumbent more attractive to first time riders. Imagine new bent riders renting bikes for the first time and not zigzagging on the trails.

Now that this is posted, it is in the public domain. If anybody makes a lot of money off this idea, please remember where you read it first.

Why does the seat have to be so close to the rear wheel? If the seat is moved forward, the weight distribution on a LWB becomes better. The bad thing is that the already long wheel base becomes longer.

If you move the rider forward, you get hard interference between the crank and the front wheel. You can, however, move the rear wheel further back, with the same complications as noted below for SWB.


On a SWB, if you move the seat away from the rear wheel by lengthening the wheel base, it will make the bike easier to steer. You can make the wheel base comparable to most DF frames. The penalty of lengthening the wheel base is higher stresses for a given tube size and more weight.

I think you're behind the times on the SWB issue. The wheelbase of my Trek 7500 is 40.5 inches. Can you name a currenty-produced SWB with a shorter wheelbase? 'Cuz I can't find one. Most are 41-45 inches, with highracers being 45-48 inches and my lowracer at 50.5 inches.

I am translating 'everyday usability' to mean practical for both club rides or commuting. Here's my wish list.
1. no-hands stable
2. 20-24" seat height
3. disc brakes
4. brackets for lights built into the frame
5. brackets for fairings built into the frame
6. room for fenders and 38mm tires at the same time
7. waterproof, lockable hardshell carrying capacity available at a reasonable price
8. no chain marks left on trousers
9. sub-25 pounds (11.3Kg)

I think you're behind the times on the SWB issue. The wheelbase of my Trek 7500 is 40.5 inches. Can you name a currenty-produced SWB with a shorter wheelbase? 'Cuz I can't find one. Most are 41-45 inches, with highracers being 45-48 inches and my lowracer at 50.5 inches.

I am translating 'everyday usability' to mean practical for both club rides or commuting. Here's my wish list.
1. no-hands stable
2. 20-24" seat height
3. disc brakes
4. brackets for lights built into the frame
5. brackets for fairings built into the frame
6. room for fenders and 38mm tires at the same time
7. waterproof, lockable hardshell carrying capacity available at a reasonable price
8. no chain marks left on trousers
9. sub-25 pounds (11.3Kg)


You are right, I am behind the times. I tried several bents 12 years ago and ended up with a LWB. That is all that I have ridden for 12 years. I also agree with your list but would like to add a few things to it.

1. Some way to see behind you. There is no place near your head to mount a mirror except on your head. If the mirror is far from your face then it has to be large to do any good especially for people with less than perfect vision like most older people. If you have USS A big mirror on the frame either sticks way out and gets in the way or you end up looking at yourself. How about an aerodynamic periscopic mirror, or a rear view mirror suspended above your face like in a car that is supported from behind, or a small camera and display.

2. A shifting mechanism that can shift gears when you are not moving.

3. Accessory brackets for quickly adding and removing accessories like a faring, canopy, or extra luggage carrier.

4. Canopy or other light weight low wind resistant covering for protection from the sun and rain along with a fairing. Leave it open on the sides for minimal impact from cross winds.

5. Quick release brackets on the front and back so you can chain bikes together in tandem.

6. Access to the inside of the frame tubes for storing things like pumps, tubes, tools, or batteries.

7. Chain protection so it does not get dirty or wet and rust.

After you get done with your project could you share the results on this web page?

Cheers guys some awesome ideas. Youve covered quite a large area and many topics. Im liking the idea of built in lights or a mast with lights on it. My team and myself have been discussing a drivers ability to see the rider when on a recumbent, this is a major safety issue that we want to address. Mast mounted lights might be the answer, but bringing the riders head height might also be the answer. Personally i reckon it would be beter to optimise visibilty but keep the rider low. There would be more stability if the rider sits lower!?

Personally i reckon it would be beter to optimise visibilty but keep the rider low. There would be more stability if the rider sits lower!?

Actually, low recumbents are known to be twitchy and less easy to get used to. High recumbents are usually more stable and more comfortable (bigger wheels) and as long as the bike isn't so high that putting your feet down at the red light gets problematic, you're better off making a high bike, improving both stability and visibility. The big reason why lowriders exist is speed, and I don't think it's a very important criterion in the design of a commuter.

Actually, low recumbents are known to be twitchy and less easy to get used to. High recumbents are usually more stable and more comfortable (bigger wheels) and as long as the bike isn't so high that putting your feet down at the red light gets problematic, you're better off making a high bike, improving both stability and visibility. The big reason why lowriders exist is speed, and I don't think it's a very important criterion in the design of a commuter.
I've heard this before, but I don't know were it comes from. Perhaps old extremely-short wheelbase models which are no longer made? Recently, a test rider on my Baron was having problems. First-time bent rider doing the typical first-time mistake of trying to push the handlebars around. I told him to take a deep breath, then let it out and relax. It took about another lap of the parking lot before you could see something go CLICK! Then he got this big smile and started tracking perfectly. Low bikes are no harder to maneuver than tall ones; it's all in the geometry. Rake, trail, steering angle, and seat angle are all important factors, and relatively independent of height. Well, trail depends on height, but a proper design will account for it.

I found this bike
http://tinyurl.com/5rrel
shown with its builder, to be pretty easy to ride (but horribly slow.) The difference is the upright seating.

it's all in the geometry. Rake, trail, steering angle, and seat angle are all important factors, and relatively independent of height. Well, trail depends on height, but a proper design will account for it.

Not quite: with big wheels, you get more gyroscopic effect, which goes a long way to make a bike more stable at speed. I rode a friend's Baron in a group ride the other day (we swapped, he rode my Condor) and we both agreed that the Condor was easier to get used to if you come from the DF world, because it behaves a lot more like an upright.

But yes, you're right, after a little while, anybody can ride anything he's gotten used to (heck, people ride Flevos, so anything is possible :) ). The only reason I mentioned this is for first-timers: since Twallis is designing a commuter bike, I reckon it shouldn't have too high a learning curve, as to not scare away potential buyers who have never ridden a bent before.