Forester has no problem speaking against recumbents.
 

I just re-read the part of Effective Cycling, (I decided to do this prior to burning it), about recumbents. He states he test rode some, liked the long wheel base better then the short, but still does not recommend a recumbent for urban road riding.

John speaking out against recumbent probably comes as no surprise considering all of the other things he speaks out against. But he did not ride one long enough to even attempt to make any sort of opinion about it.

He did test ride both long & short wheel base recumbents & states he had an easier time with control & stability on the long wheel base vs. the short. But some of his comments & opinions about the short wheel base recumbents & about any recumbent is false.

I ride a recumbent, it is a Vision R40 Short Wheel Base, or SWB with Over, or Above Seat Steering, or OSS/ASS. I have no problems riding it in any urban, sub-urban or open road conditions. I have been doing so for the past 6 years. Everything Forester says about riding a recumbent & the problem associated with one is for the most part a myth or false. I can get started while on a hill if I have to stop on one. Yes it is harder, but possible. Yes it is slower to ride up a hill, but it is possible.

The issue with remaining stable on descents is totally false. I almost fell out of my chair laughing so hard at it. I have gone downhill at almost 50 mph & remained perfectly stable. And keep in mind my bike is a SWB. Of course, like with ANY other bike you ride, road bike, mtn bike, etc., you ride according to what the conditions permit. There are downhill sections in my town I feather the brakes while riding & there are sections where I am balls to the wall pedalling as hard as & as fast I can & remain perfectly stable while doing so. The reason is I know the roadway & what the conditions are & what I can & can not do.

When I first started riding mine I would not have ridden it in the manner I describe above. Why? Well I did not have the experience I do now with it. It took me time to learn how to ride & control it. It took a whole week of riding it on a high school track, then an empty parking lot to learn how to control it enough before I took it out onto the roadways. A recumbent is just not the type of bike you jump on & expect to handle like a diamond frame bike. I think John expected this when he rode the ones he did.

With all of these myths & false hoods John wrote about recumbents it makes me wonder what else he has written, commented on or stated & has no proof, other then temporary exposure to it, like with riding a recumbent.

The bottom line John is experience is everything when it comes to riding a bike. You did not then, at the time you wrote Effective Cycling, & I doubt you have anymore experience with riding recumbents even now to form any kind of opinion about them, they way they handle & are controlled, etc.

Before you make such comments again on recumbents try owning & riding one for at least a year. Then maybe we'll listen to you because you'll have a solid bases for your opinions on such things. This goes for anything you write about for that matter.

I wouldn't worry about it NC. He gave recumbents as much thought as he gave his bike path "study".

I wouldn't worry about what anybody has to say about recumbents. Lots of people disparage them and have all kinds of pre-conceived ideas and stereotypes, but lots of people also like them and know from experience what they are all about. Focus on the latter group and ignore the rest.

Never throw anything away like that. There's always something we can use, even from sources we are in conflict with.

How does your Vision R40 SWB/OSS handle during a steering displacement test at speeds of over 40 mph?

WTF is a steering displacement test? Never heard of it, it is not in Effective Cycling, nor on wikipedia. If it is steering the bike on a curve to maintain control, it handles very well & very stable.

One of the hills I go hard & fast down is Singing Hills Blvd. I have hit 45 mph on it. It is a divided 4 lane roadway, the hill section is about 3/4 of a mile long & has some 2 very nice sweeping curves, very smooth concrete for the surface. I am able to maintain control at the the higher speed & stay in one lane while I am doing so. If this is steering displacement, then it handles quite beautifully.

If not, then I have no idea what steering displacement is, nor have I ever heard of a test for it. It sounds like another term you created to make yourself sound legitiment that you can use to legtimize your propoganda & if we do not perform these tests with our bikes & can not control our bikes while in a steering displacement situation then we are not riding in accordance with your style & doctrine. But before I make a decision on that do tell, what is steering displacement?

Almost too late. It is in the grill waiting to be used as starter fuel for the charcoal briquets for tomorrow, provided it does not rain. If it does rain the moisture will certainly damage the book even from inside the grill as it is sitting on my back porch. Even with the porch being covered if the wind blows hard enough tonight it will probably knock the grill over, as it does every time we have severe thunderstorms, & that will cause serious damage to the in-effective book. When I say covered porch I mean roof only. There is nothing between the supports that hold the roof up, very easy for the wind to blow onto & around the porch. It has blown so hard my grill has ended up in the middle of the back yard & the tet-a-tet as ended up on the patio. With any luck the wind will blow the grill over, catch the book as it falls out & it will disappear somewhere carried away by the storm. I'd wish for a tornado to take it away but I don't want my house damaged in the process, though we are under a tornado watch, which could turn into a warning at any moment.

Very true! It's great to put you to sleep with. If you're not into reading absurdly boring tomes to get to sleep (natch, nightmares!), then it makes great hamster bedding.

Personally, I find the smooth pages to be the perfect camping toilet paper.

EDIT: To stay on topic: it's a pity he has a problem with recumbents. I think they're wonderful devices.

So what the hell is steering displacement? My search on the internet has yielded no results for a definition. Sounds like another bull**** term made up. Anyone can answer, not just HH & JF.

Hmmm, I'm also wondering what steering displacement is. I tried searching for it at Sheldon Brown's site, and didn't seem to find anything.

Maybe its what makes a bicycle turn. Maybe HH or JF can start another new thread on this thrilling and crucial subject.

I use a recumbent for urban road riding, round trip to work and back, about 30 miles. I don't have any problems with it. In fact, I slipped on a wet curve a while back (my error, wet and oily curve,) and I got a little rash. But on my upright bike a few years ago, I went over the handlebars after a pedestrian intentionally knocked me off my bike. The "rash" was on my face, not pretty, and I spent the afternoon/evening in the emergency room. Today, I still have to wear a mustache to cover an ugly scar above my lip.

Based on my experience, my recumbent can be safer than my upright for that reason. But I can't say I've done any other kind of testing to prove my belief. It just seems safer because I am not likely to land on my face by going over the bars.

However, when I started riding my bent, I had significant handling issues to overcome (my bent is a short wheelbase, tends to have a longer learning curve.) But I've read about some of the more stable long wheelbased bents having some quirks in the steering, too.

I can easily imagine anyone riding a bent and deciding it was not good for commuting. On the other hand, I love mine so much, I was willing to ride it long enough to master the differences. Now, I'm fine. (Keep in mind that bents have many designs and vary in their handling characteristics.)

Hey, I remember when I was little, I had just as much trouble learning to ride a regular bike, probably even more so.

That said, this thread seems to be less about recumbents than about attacking John Forester.

War makes strange bedfellows, does it not?

Your search - "steering displacement test" - did not match any documents.

One wonders where the civility has gone. Just because you are ignorant of some rather basic control system theory does not mean that my mention of it has been expelled from the anus of a cow.

A displacement test, in control theory, consists in inserting a sudden displacement input to see how the system responds. The system may recover into stability, or it may not, and the time durations or oscillations may be significant. I described this as steering displacement, which means that the sudden displacement consists of a blow or jerk to the handlebars. That's all.

In the particular case being discussed, the conditions were at high cycling speed, as on a descent.

Basic control system? Really? How many of us have looked for a definition of Steering Displacement or a test for it & found nothing? Well more then one, at least more then one of us has posted about it anway. I have a feeling others have searched for it & have not posted about it, yet. I encourage them to post about their findings on this topic, what ever they may be. It would seem we are all ignorant of something this basic control system, because until now it seemed to not have existed until John Forester created it, or at least created the name for it. But maybe it is described under a differant name.

John, if this term you came up with is described under a differant more familiar name then please post it. Otherwise it sounds like something you made up out of the blue, for what ever reason. Whether you created the term in the past or just recently I don't know & the timing of it is irrelavent. But you need to come up with a bases for this theory or it is nothing more then just bull**** at this point. Please read below.

First I have no reason to test such a thing with the bike I own now nor have I ever had to on any bike I owned in the past. I mean why would one need to do this? What would it prove anyway? Other then potentially putting myself at risk of a crash. Why the need to do this on a bike? I have never even heard of such a test nor the need for an end consumer like myself to conduct one.

If you are talking in terms of swerving to avoid a hazard in the roadway I have never had to give the handle bars a sudden jerk to avoid anything like that. I either know the roadway ahead of time & for things that may have changed since I have ridden on it last I have enough control of my bike to be able to steer around a hazard or take the best path through it & still maintain control.

John, you have explained what steering displacement is. I have stated I have never had a need to do this & ask why is there or would there be such a need, other then idle curiousity, to conduct such a test at a high speed on a bike.

Now that you have explained the what, it is time for the why. Also explain your own findings with this test on a bike, any bike, but more specifically a recumbent. I would like to see some sort of statistic on the differance, based on your experience alone, of how a diamond frame road bike handles when you conduct this test compared to a recumbent.

I have called you on this, it is time to pony up & show your proof of why steering displacement is even needed.

NC, your animosity is absolutely overwhelming.

The steering displacement test is a means of evaluating the stability of a bicycle, any bicycle, that is not obviously already unstable. I have no reason to expect that diamond-frame bicycles and recumbents have any class differences in this. Each one is different.

I don't know about "steering displacement" but I can say for certain that I can go much faster down a hill on my Lightning recumbent bicycle than on my upright bicycle, and as I'm going down the hill at the highest speeds I can muster I feel exceedingly more stable and in control than I do on an upright bike. I've had to brake at the bottom of some hills where I've gotten into the high 30s on curves and the bike brakes beautifully, too. Even if I can get a skid going with my rear wheel I feel in control.

The trike is a little different. I have gotten up to 40 on my tricycle. When I first was trying to imagine riding a tricycle I could not imagine how they could possibly go fast without flipping over at the drop of a hat. In reality, my trike feels extremely stable at high speed. With the trike, however, the steering gets a little scary at high speed as does the braking. My particular trike requires a very light touch for braking and steering. No panicking is allowed!

At low speed, both of these recumbents pose their own individual problems with turning. At low speed the recumbent bike can have wheel interference with the pedals. This is not unlike how some road bikes can strike your toe with the front wheel in low speed turns.

The trike on the other hand has its own peculiar problem in that at very sharp low speed turns you can get a bit of wheel flop and then the trike will flip.

You can avoid both these things just like you can avoid hitting the front wheel of a road bike with your toe, or avoid hitting your panier with your heel. Neither is a big deal that makes the bike dangerous or impossible to operate safely.

Stability test are the norm when designing any vehicle, be it bicycle, motorcycle, car, truck, boat, ship, plane or rocket. Some of these stability test include the effects of an instantaneous perturbation to the steering control system or the steering surfaces. Some of these test include the operator as part of the steering system in the test, while others only test the vehicle without the operator actions. Different industries use different terms for these stability test. JF’s term “steering displacement test” is a reasonable description of some of these test. Even if it does not show up in google searches, so what.


JF states “I have no reason to expect that diamond-frame bicycles and recumbents have any class differences in this. Each one is different.”
I agree with this provided the test does not include the operator as part of the steering system.
When the operator is included as part of the steering system, there is at least one factor which differentiates a bent from a diamond frame. On a diamond frame, the cyclist can lift his butt off the saddle and disconnect the center of mass from the lean of the bicycle (in other words - the cyclist can significantly change the lean of the bicycle without significantly changing the center of mass). On a bent, I do not, and know of no other bent rider who lifts their butt off the seat and then leans the bicycle independent of the center of mass.
The lack of this tool is one reason a bent requires more cyclist skill and more practice to ride with the same precision.

Was your testing performed on a smooth road without any steering displacement; or did you intentionally insert an equal steering displacement into the handlebar for each bicycle you tested or was steering displacement inserted by riding on an uneven potholed road?

I hope you are being sarcastic there.... if not, do you guys really think we all should do insane tests on the stability of our bicycles to make claims like "my bike handles better then that bike for me"? :eek:

Well, from an engineering standpoint, it would be a test to failure mode type of experience. I agree that the DF is more stable under certain circumstances because the ability to shift the center of mass is far greater. Shift the C of M and you alter the whole equation,after all. This doesn't mean I think bent = bad, all it means is a different tool for a different application: eg: I wouldn't use a hammer to set a screw.:p

AN example: I could not imagine in my wildest dreams doing some of the stuff done offroad on a mountainbike on any recumbent, whether it be long wheelbase, short or a trike!:eek:

Among diamond frame upright bicycles many varying geometries are possible; steering rake and other design parameters can be wildly different from bike to bike. With recumbents the range in designs is even greater. I don't know how anyone, especially an engineer, can make the types of sweeping generalizations about these two classes of bikes that AJ has made here.

You still haven't answered the questions as to why this is even needed. Or at least why an end consumer would want to or even need to do this. I can see if the manufacturer would need to perform such a test & then only when they are trying to produce a new line of bicycles.

Can anyone answer as to whether or not manufacturers perform these types of tests on the bikes they produce? Can anyone also answer as to why an end consumer would want or even need to conduct such a test?

This is kind of like asking the pilot who purchases a new air plane to test it the same way a test pilot would. Why?

Or better yet suggesting that someone who purchases a new car to perform a safety crash test the same it is done in the test lab. Only instead of test dummies the person who bought the car is the one behind the wheel when they crash into the wall ro what ever.

I would rather rely on the test data the manufacturer provides me with then conduct the tests myself, if I want to read & study it I have a good idea on where to find it.

Of course you have no reason to expect the class differance between DF's & 'bents. You know very little if anything about recumbents. At least you finally admit a fault in something. But as a former DF bike rider who has ridden a recumbent for the past 6 years I assure you there is a huge differance. I know Diane & other recumbent riders can back me on that one. Especially if they still ride a DF bike.

The thing is on a bicycle the operator is part of the steering system, a major part of it. But let's give the benefit of the doubt here. Has anyone ever heard of a test lab similar to how cars are safety tested? Where the bike could be rigged to a device that propels it along a track to test steering displacement with a test dummie to simulate a humans weight, etc.?

Though it is hard to shift the center of mass & center of gravity on a recumbent, keep in mind it already much lower then on a DF. In every case where I had to make an emergency manuver on my 'bent I have never had a problem maintaining control because of this. Where if it was a DF I would have had to do something in addition to steering control to lower my C of M & C of G.

Ahh, Google...the new Encyclopedia Brittanica.

:)

If it's not on Google, does it exist? Philosophically speaking, like the proverbial tree falling in the woods, if nobody hears it, did it make a noise?

I'm gonna try Chinese Google first chance I get. I'm gonna see if I can pull up anything significant about Tiennamen Square. My guess is no.