Talk:Recumbent bicycle

A picture would be helpful. -Frecklefoot

Isn't it possible to exert more force while peddling a recumbent bike, as you are able to brace against the seat, whereas in a normal bike the force you exert can never be greater than your weight? --Neil

I noticed a discrepancy betweent this page and the bike page. The bike page quotes a much higher speed record for a rcubet bicycle set by a Canadian. I don't know enough to determine who is right but maybe the discrepancy should be addressed? -- Fred

Recumbent bikes sound cool! - a guy

Expanded a bit, removed some probable vandalism, structured a bit. More needed on recumbent culture (and, IMO, on the competition scene) Just zis Guy, you know? 12:47, 7 October 2005 (UTC)

Work in progress by Jus zis Guy

I am working on expanding the History section; I will also incorporate some more info from Gunnar Fehlau's "The Recumbent Bicycle" which is a pretty good authority. - Just zis Guy, you know? 11:56, 8 October 2005 (UTC)

Recumbents for Handicap and elderly

I am post polio with strong upper arms but weak legs in need of exercise. I simply need a low cost multispeed ratio to allow both leg and armpropulsion. Is there any available?? jbaum12@msn.com

Standing on hills

82.143.162.72 11:11, 29 January 2006 (UTC) There are references to the 'disadvantage' of not being able to stand when going up hill. Should there be something in these sections that mentions that it is not energy-efficient to stand when riding an upright? Try doing it when there is snow on the ground and you will feel how little of your pedalling is turned into forward movement and how much is turned into wheel-spin.

Think about the question and your example. The reason the wheel slips when the rider is standing, but not when sitting, is because it's pushing harder across the ground than when the rider is sitting. When you're on asphalt, the friction is great enough so that all that extra energy that causes the wheel to slip on ice is used to propel yourself forward. Temple 21:30, 2 February 2006 (UTC)

See the reference in the cycling page to comparative studies on standing vs sitting techniques - more power standing, just as efficient. Standing also move weight off the rear wheel onto the front, and may produce a more pulsing power stroke unless you have pretty good technique. --203.59.191.106 (05:09, 2 March 2007)

While the study did not find a difference in "efficiency", it did report that "heart rate was about 8 bpm higher when standing compared to seated uphill. Ventilation was also higher." "Standing is a bigger stress on our aerobic and cardiovascular system." Not a good idea if one is already close to their maximum exersion level. Standing and trying to maintain the same pace can lead quickly to going anaerobic. -AndrewDressel 19:02, 2 March 2007 (UTC)

Yes, higher heart rate, higher ventilation. (Advisable - who's to say? Riding out of the saddle is a little to common to say its in advisable.) So what we have is actual higher power output, that can take you anerobic quite quickly. Just the thing for getting over a hill and having the recovery over the other side. Nothing unusual there, and very much shows why bents are seen as poor performers on hills. You can't get out of the saddle to develop a short period of very high power, anerobically.

There is a lot of nonsense going about on 'pushing harder against the seat back' than is possible when 'pushing against gravity'. At a 60 or higher cadence, you are not going to push your weight up into the air as you pedal an upright. You will alleviate a little of the weight that is on the saddle is all. -203.59.191.106 (05:09, 2 March 2007)

I don't think anyone is talking about 60 rpm here. The perception is that, for very slow cadance, up a "crank stopper" for instance, one can generate more force by pushing against a seat back than by lifting ones entire body weight. Since I can press with one leg at the gym more than my total body weight, I'd have to agree with this perception, although I have to admit that it is less efficient due to energy lost in the compression of not-perfectly-elastic seat and flesh. -AndrewDressel 19:02, 2 March 2007 (UTC)

If we are talking about getting up a hill, then we must be talking about higher performance, so we must be talking about at least 60rpm. I thought 60 was pretty low, if you are tackling a hill. If you have a 'crank stopper' you obviously don't have the appropriate gearing, and the experience is usually as you come to a stop, defeated by the hill. Yes, you can generate more force at this low crank rate than on an upright, but that is a disfunctional technique, damaging knees, lower efficiency. I don't think this riding mode should be presented as something that recumbent cycling gives you. Is there any advice anywhere that actually says not to 'spin'? is there any experienced rider that would advocate this? Pretty clearly not.

Witness the lack of verticle movement as a road bike rider passes by. Standing up on the pedals does not alter the gravity effect, but allows you to pass some of the pushing effort from the leg alone over to the rest of the body, which it does by rocking the hips slightly to aid the stoke and reduce the legnth of the stroke as experienced by the leg so the knee is less bent at the apex of each stroke and is postioned to handle the extra power.

If you see that logic, then you also understand why new bent riders struggle uphills. It also explains the trend to shorter cranks. Its because the upper body is isolated and cannot be invoked as it can on an upright bike. Bent riders compensate by spining higher (although not higher than other good riders do) and by building more leg mass.

There is a lot of talk of the extra weight of a recumbent accounting for the poorer hill performance - a factor, but not an explanation - if the model I've suggested is right. -203.59.191.106 (05:09, 2 March 2007)

[responding to the para below]'Motionless in the context of not going up and down' and 'isolated from the pedalling activity' are not the same thing. Imagine you are at the finishing line watching a UCI road bike race as the leaders sprint towards you ... now, what movement do you see? You see sideways swinging of the frame, because they are effectively using it to lever the pedal against the foot with each stroke, applying the whole body to the task of generating maximum power. I'm tempted to suggest that no rider can generate more power on a recumbent than they could on an upright. (OFFTOPIC: While many recumbent enthusiasts bemoan the UCI ruling to exlude bents from those races, if you observe the quite different scope for riding technique and the importance of that and aerodynamics and teamwork to the natuer of the cycling sport, you can see that it may have been a decision to preserve the nature of the contest, rather than a spiteful 'I don't want to compete against recumbents' decision.) —The preceding unsigned comment was added by 203.59.185.129 (talk) 01:34, 3 March 2007 (UTC).

I don't understand your last point. First you mention the motionless upper body of efficient seated hill climbers, and then you seem to attribute poor recumbent climbing performance to an isolated upper body. Extra weight seems a lot easier to believe. -AndrewDressel 19:02, 2 March 2007 (UTC)

'Motionless in the context of not going up and down' and 'isolated from the pedalling activity' are not the same thing. Imagine you are at the finishing line watching a UCI road bike race as the leaders sprint towards you ... now, what movement do you see? You see sideways swinging of the frame, because they are effectively using it to lever the pedal against the foot with each stroke, applying the whole body to the task of generating maximum power. I'm tempted to suggest that no rider can generate more power on a recumbent than they could on an upright. (OFFTOPIC: While many recumbent enthusiasts bemoan the UCI ruling to exlude bents from those races, if you observe the quite different scope for riding technique and the importance of that and aerodynamics and teamwork to the natuer of the cycling sport, you can see that it may have been a decision to preserve the nature of the contest, rather than a spiteful 'I don't want to compete against recumbents' decision.)

Safety of Recumbents in MVAs

I would think that this wiki page would be better served by discussing the safety implications of being involved in an automobile accident in a recumbent. While it's important to promote the pros of riding recumbent, it's a disservice to readers to not openly discuss the cons.

When a car hits an upright bicycle, generally the impact will be at the riders lower leg level, 2-3 feet below the riders centre of gravity. This will likely throw the rider up and over the vehicle. However on a recumbent bike, the impact will be at the riders legs, hip, and torso, directly at the centre of gravity. This will cause the rider to absorb more of the impact energy and there is a greater chance of being run over by the vehicle.

Further, it's a valid point to recognize that, with the head closer to the ground, there is less visibility over cars, bushes, newspaper boxes at intersections, etc... Temple 21:36, 2 February 2006 (UTC)

That is entirely speculative. I know of absolutely no credible data to support the suggestion that a 'bent rider is likely to come off worse in a car v bike collision - and one of the common causes of fatal collision is a car pulling out into the path of the bike; in these circumstances hitting feet-first is likely to be a great advantage. No two collisions are the same. I have no idea how comon car v 'bent collisions are, they seem to be very uncommon indeed even given how rare the bikes are (I only know a few dozen recumbent riders personally), but that may be because the kinds of riders who ride 'bents have some idea how to ride properly so they don't get hit in the first place (and they are less likely to ride on footways, which is very dangerous). I think it's almost certainly the case that recumbent safety is neither better nor worse than for "wedgies", but that there are slightly different issues. - Just zis  Guy, you know? ^[T]/_[C] 22:39, 2 February 2006 (UTC)

So why are only half of these issues mentioned in the article? —The preceding unsigned comment was added by 81.235.136.245 (talk) 01:29, 24 February 2007 (UTC).

I know of two stories reported to me where people have come off their recumbent. Each one was fearful of how much worse they'd have been if they had been on an upright bike. But this is an encyclopedia, it does not contain stories.

Userbox

If you like userboxes (userboxen?), you can give recumbent riding some loooove with this one: Template:User bentcycling. - FlyingOrca 14:43, 23 April 2006 (UTC)

# 2.2 Healthy

Pardon me if I am dearly wrong but shouldn't that read 2.2 Health

POV

The article seems very much like it was written from an apologetic standpoint in favor or recumbent bicycling--it refers to upright bicycles as wedgies instead of their traditional name, and in the disadvantage section even tries to explain away at least one quantitative disadvantage (price). There are also several non-encyclopedic phrases, especially the things that appear in parantheses "(Test ride... test ride... test ride...)" -Mance 21:57, 30 June 2006 (UTC)

Well, it's true that bent riders do tend to be an enthusiastic lot... but I think without exception they would say that is because recumbents really ARE superior. Be that as it may, it wouldn't hurt to tone down some phrases. The "wedgie" thing is worthy of inclusion, being quite widespread, but perhaps it should be presented in another fashion? (e.g. Recumbent riders commonly refer to upright bikes as "wedgies" due to the percieved comfort advantages of recumbents and to the perceived comfort and health disadvantages of uprights, such as neck strain and penile numbness.) As for the "Test ride" thing, I agree that it's non-encyclopedic. Care to take a stab at some edits? - FlyingOrca 00:43, 1 July 2006 (UTC)

Biggest problems I see really come down in the Advantages/Disadvantages, which basically seems to be saying that there are many ("too many to list") advantages to a recumbent bicycle over an upright bicycle and that all of the perceived disadvantages aren't disadvantages at all, just misconceptions. Did a rewording and reformatting, but I attempted to keep all factual and NPOV content. Lemme know what you think. -Mance 05:34, 1 July 2006 (UTC)

I'm liking it so far. I'd do some work in this myself today, but I have a client breathing down my neck for some paying work. ;-) FWIW, the health and comfort benefits are probably the most important to recumbent riders, and are often the reason people get their first recumbent; I'd strongly suggest their inclusion in some form. Cheers! - FlyingOrca 11:53, 1 July 2006 (UTC)

Oh, they'll definitely be in there--it's just that the hour was waxing late, so I needed to break it off and get some sleep. I -am- going to tag all of it with needs citation--getting a few scientific (or otherwise) sources in there will significantly reduce the fanboy feeling it gives off now.-Mance 15:17, 1 July 2006 (UTC)

I have made some contributions to the existing injuy sections of the page. I noticed that mention of the "leg-suck" roll-over injury had been removed. I have reinserted it but freely admit that there may be no citable source for information about this type of injury. At most I can vouch as a participant on several recumbent discussion groups, that leg-suck is one of the most often described injury types effecting novice and experienced bent riders alike. The spiral femur fracture injury class which stood unchallenged in the article is much less common. Ironically, I have direct (unverifiable I know) knowledge of at least three cases of this devastating injury. While I am myself a bent fan, I would appreciate it if we could find a way to keep these safety warnings in the article while somehow meeting Wikipedia's verifyability standards. Both injury types come up in periodic discussions on the widely respected Bent Rider Online message forums.--RZech 17:57, 6 July 2006 (UTC)

Inability to "bunny hop"

Are recumbent bikes more difficult to ride over obstacles? On an upright bike you can lift the front wheel over obstacles and redistribute weight for the back wheel, or if you want to clear an obstacle at speed just bunny hop straight over it. I ride a lot around the city I live in and find I am always going up curbs, over ditches, over medium strips etc. Riding a recumbent bike would be very inconvenient for me.

That's a good point. Anyone want to weigh in?-Mance 09:14, 6 July 2006 (UTC)

It's true. It's very hard to unweight either end on a recumbent.

I say, use the right tool for the job. Urban commuting probably does not benefit from a recumbent, but a mountain bike would be useful. A longer ride benefits from the comfort of a recumbent. Walt 11:43, 6 July 2006 (UTC)

I used one every day for some years as my commuter bike, first on a 15 mile round trip then on two short trips with a trian journey in the middle. I now have a Brompton which is more convenient on the train, but the 'bent was fine in every other respect. No, you can't bunny-hop. I can't do that on a wedgie either. Or on the Brom, for obvious reasons. I don't think it's especially relevant. Just zis Guy you know? 12:00, 6 July 2006 (UTC)

Well, it is sorta relevant, because it widens the gap between the recumbent as a recreation vehicle with the upright as a utility vehicle.-Mance 17:08, 6 July 2006 (UTC)

Not really, I know plenty of regular recumbent commuters. Guy 17:33, 23 October 2006 (UTC)

Those darn Humans: File:Trial bent.jpg--RZech 18:22, 6 July 2006 (UTC)

Jim Parker "weighing in" on the "unweighting" issue... There are many recumbent configurations and I am not familiar with all of them. However I am very familiar with the Cruzbike, which is a SWB PBFWD recumbent with dual suspension. At slow speeds, the bike can be ridden up full-size city curbs. I believe having the front wheel under power allows it to "lift" the front end of the bike over the curb, rather than just slamming into the curb as a rear-drive recumbent would do. At higher speeds, the bike can be easily lifted in a fluid motion over the curb. I demonstrate these techniques on video Cruzbike curb climbing [User:jp308| Jim Parker] 21 January 2007

Unsourced

I removed an anonymous addition: "Recumbents are also harder for motorists to spot, making accidental collisions more likely; for this reason many recreational recumbents sport an easily-seen banner on a pole attached to the back (though this increases air resistance)."

This is unsourced. I know of no research basis for this, anecdotal evidence suggests that recumbents are sufficiently unusual that they get noticed very easily (the "wtf? factor"). That siad, as this is WP:OR I think we wait for a credible source first. Just zis Guy you know? 15:52, 7 July 2006 (UTC)

A researcher in the UK found that traffic gave him a wider berth when he dressed as a woman wearing a wig. That study may supports the claim that the way you look influences how traffic in general flows around you. There is no doubt that in the mind of the general public, nearly everyone I meet says this to me "those low bikes look dangerous, someone might not notice you". I think its fair to mention that many people think this, it may be true but there is no clear study either way. Being so low does seem to result in accidents, at least its not hard to find someone report they were hit on the trike by someone who didn't see them. Also not mentioned is the difficulty of riding defensively if you have less information about where the traffic is moving.

Unsourced claims in Advantages section

"Handling. Because of its low center-of-gravity, the recumbent bicycle can handle sharper turns at greater speeds than a traditional upright bicycle."

Any idea how this might be true? If the same physics apply, then a recumbent will need exactly the same lean angle as an upright bike to make the same radius turn at the same speed. True, the combined center of mass of the bike and rider will be displaced from the vertical less, but that doesn't necessarily give it an advantage. The only limiting factors for both types of bikes should be friction of the tires on the pavement, interferance from other parts of the bike touching the ground (pedals or seats), and the riders nerve. -AndrewDressel 04:25, 3 August 2006 (UTC)

Having a low CoG means you can change direction faster, because the mass has a lesser distance to move for a given amount of lean, but also adjustments will be less fine (all things being equal which they never are).

I can't corner at 50 on a wedgie... Guy 17:32, 23 October 2006 (UTC)

"Stability. Because of a lower center of gravity and a more aerodynamic design, recumbent bicycles enjoy greater stability than traditional upright bicycles. In addition, panniers can be mounted low, under the rider, which gives good handling and stability when loaded."

How does a lower center of gravity make recumbents more stable? In fact, J. Fajans [1] claims the opposite, as do Whitt and Wilson on page 232 of Bicycling Science. Even the first advantage listed in the section immediately following contradicts this. -AndrewDressel 04:25, 3 August 2006 (UTC)

Agreed. But lowering the CoG seems to offset the problems with the pendulum effect. Low riders improve ride in a way that high loading does not, don't ask me why. Guy 17:32, 23 October 2006 (UTC)

A longer wheel base brings stability, in that steering corrections more slowly alter that balance. Low racers have longer wheelbases than normal bikes. Bill Patterson's book Lord of the Chainring may be helpful resource. In fact, he might be enticed to help here. Is there a bicycle handling wiki page yet?

External Links

I cleaned up some manufacturers from the External Links section. These shouldn't really be in a wikipedia article. This is an encyclopedia, not a commercial directory. One of them, "Red Rim cycles", has even added themselves back in almost immediately. Before this goes into an edit war, I think there should be concensus from other editors. Wikipedia:External links --Vgedris 17:18, 23 October 2006 (UTC)

Yup, clear them out. Link to one of the directories of manufacturers at a human power club, or BROL or something. Guy 17:30, 23 October 2006 (UTC)

Advantages and disadvantages of recumbent riding position

The current article mentions

• [The recumbent position] reduces the rider's hydrostatic pressure, thus allowing venous blood to more easily return to the heart. This physiological effect of improved circulation suggests an increase in rider endurance and/or increased power output on long rides.
• the [recumbent] rider is unable to stand on ascents
• the [recumbent] rider can push against the seat to generate more pedal force than is possible on an upright bike because on an upright, the rider cannot press a pedal downward with any more force than his own weight
• recumbents have won hill-climb challenges and races with substantial ascents against uprights in mixed fields, and have been ridden over the mountain stage routes of the Tour de France.

All unsourced, of course, and to which I would add:

• While pressing against the seat back may allow for more force, it comes at the cost of losses due to compressing imperfectly elastic material: muscle and other tissue of the back and foam or plastics in the seat. Any energy spent raising the CG of the rider against gravity may be recovered.

On the other hand here are some citable points:

• A study by Bussolari and Nadel (1989) led them to pick a recumbent riding position for the Daedalus flight even though the first English Channel crossing was accomplished with an upright position. This is according to Wilson in his third edition of "Bicycling Science" on page 72.
• He continues on page 86 to cite Drela (1998) who "confirmed that there was no significant difference in power output between recumbent and conventional bicycling."

Anyone else have any data points that can be referenced? -AndrewDressel 17:46, 6 December 2006 (UTC)