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SchoonerRat
06-22-2013, 11:19 PM
At least it's almost like riding a bike.


http://schoonerrat.com/wbf/rans.jpg

On my first ride, the grips were way too high and way too close to my chest and the bike was way too twitchy.

Now, the grips are a little too high and a little too close to my chest and the bike is a little twitchy.

I've collapsed things down as far as I can without cutting or swapping out tube.

I figure that some of the twitch is just me not being used to the geometry of this thing. I need a little more time behind the wheel before I try to tackle the So Cal freeways.:d

There used to be a shop in town where you could take this thing and not get laughed out of the place. He's not around anymore. This is the first place I could think of for advice.

Gerarddm
06-23-2013, 02:41 AM
I think recumbents are dangerous as hell.

SchoonerRat
06-23-2013, 03:47 AM
I think recumbents are dangerous as hell.

I think bleached blonds with big knockers are dangerous as hell. I think mescal is dangerous as hell. And don't get me started on chocolate.

Are your fears as rational as mine? Care to expound a bit?

The Bigfella
06-23-2013, 05:52 AM
Sp, what's the question again?

Bobby of Tulsa
06-23-2013, 05:53 AM
I think bleached blonds with big knockers are dangerous as hell. I think mescal is dangerous as hell. And don't get me started on chocolate.

Are your fears as rational as mine? Care to expound a bit? Chocolate yes, the others not so much.:)

Ron Carter
06-23-2013, 07:08 AM
It's twitchy because on a vertical bike you instinctively pivot at the waist to balance. Leaning back on the seat you lose this. You have to steer to get the same effect. Seat time will make it second nature and the "twitches" will be much reduced in amplitude.

Rich Jones
06-23-2013, 07:54 AM
Twitchy could be because of the small diameter wheels. Bigger wheels, better stability. Centrifical forces, physics, all that stuff.

Flying Orca
06-23-2013, 09:25 AM
I think recumbents are dangerous as hell.

Lots of people do. They tend to be people who haven't ridden them. Have you?

Flying Orca
06-23-2013, 09:27 AM
Twitchy could be because of the small diameter wheels. Bigger wheels, better stability. Centrifical forces, physics, all that stuff.

Centrifugal forces make some difference, but I'd hazard it's mostly a longer inverted pendulum that makes balancing easier on bikes with larger diameter wheels. Smaller wheels can cause other problems, though - they don't take potholes as well, for example, particularly when you can't "jump" the bike or even your own weight over the holes. That's why I stopped riding my 'bent in the city - the streets here are too rough for comfort on an unsuspended 'bent.

SchoonerRat
06-23-2013, 09:30 AM
It's twitchy because on a vertical bike you instinctively pivot at the waist to balance. Leaning back on the seat you lose this. You have to steer to get the same effect. Seat time will make it second nature and the "twitches" will be much reduced in amplitude.

I really notice this trying to start out from a stop. It's tough resisting the instinct to lean forward, up out of the seat. Ending up pointing 270 from my intended trajectory is helping to hammer that point home.


Twitchy could be because of the small diameter wheels. Bigger wheels, better stability. Centrifical forces, physics, all that stuff.

I'm thinking that the smaller wheels would reduce the gyroscopic effect making balance more difficult, especially at low speeds. I believe that the geometry of the front end is giving me most of the feel that I'm not used to. The recumbent bike puts the front wheel way out in front of the handlebars on a long lever arm. You don't just turn the front wheel around a vertical axis. The steering seems much more sensitive to small movements of the handlebars.

Paul Pless
06-23-2013, 09:32 AM
clearly you just need to ride faster . . .:D

Rich Jones
06-23-2013, 09:33 AM
I'm thinking that a centerboard might help!:D

Paul Pless
06-23-2013, 09:34 AM
maybe a small mizzen:d

SchoonerRat
06-23-2013, 09:40 AM
Centrifugal forces make some difference, but I'd hazard it's mostly a longer inverted pendulum that makes balancing easier on bikes with larger diameter wheels. Smaller wheels can cause other problems, though - they don't take potholes as well, for example, particularly when you can't "jump" the bike or even your own weight over the holes. That's why I stopped riding my 'bent in the city - the streets here are too rough for comfort on an unsuspended 'bent.

My first impressions are that this bike absorbs shock better than any upright I've ever ridden. The main attraction is that I can ride it more than a half block without my back screaming bloody murder.

Paul Pless
06-23-2013, 09:42 AM
My first impressions are that this bike absorbs shock better than any upright I've ever ridden. perhaps mostly attributable to that big ass seat. . .

SchoonerRat
06-23-2013, 09:50 AM
clearly you just need to ride faster . . .:D

A new pair of legs will take care of that.


I'm thinking that a centerboard might help!:D

It's too late to build a c/b trunk on her. It'll have to be a leeboard.


maybe a small mizzen:d

Paul?? A MIZZEN?????? You do know who you're talking to don't you?????
Bad enough that the poor thing isn't wood...but a mizzen...what are you thinking?

Keith Wilson
06-23-2013, 09:52 AM
Smaller wheels have very little to do with it. "Twitchiness" is almost entirely a function of steering geometry. You can build a recumbent twitchy or very stable, irrespective of wheel size. Trust me on this one; I'm a mechanical engineer who worked in a bike shop for quite a while, and I've build a couple of very odd bikes myself, including a long-wheelbase recumbent in 1981 - when driving a purple metalflake Lamborghini would have attracted less attention. FWIW, the one I built had a 16" front wheel and tracked like it was on rails. Unfortunately, you can't change steering geometry without bending or cutting metal. If it's not just a matter of getting used to it, a little less fork rake might improve things.

As far as safety, the only way a competently-designed recumbent is more dangerous is because it's less visible to cars. Their huge safety advantage is that falling 18" is far less likely to cause injury than falling six feet.

SchoonerRat
06-23-2013, 09:53 AM
perhaps mostly attributable to that big ass seat. . .

HEY!!!

This big ass seat has been with me for decades. I'm not going anyplace without it.

The bike's seat might help a little bit too.

SchoonerRat
06-23-2013, 10:09 AM
Smaller wheels have very little to do with it. "Twitchiness" is almost entirely a function of steering geometry. Trust me on this one; I'm a mechanical engineer who worked in a bike shop for quite a while, and I've build a couple of very odd bikes myself, including a long-wheelbase recumbent in 1981 - when driving a purple metalflake Lamborghini would have attracted less attention. Unfortunately, you can't change steering geometry without bending or cutting metal. If it's not just a matter of getting used to it, a little less fork rake might improve things.

OK Keith, you seem to be the guy with the answers I'm looking for.

While the bike was gifted to me, I'm looking at it as a long term/permanent loan. I'd like to be able to return it without any alterations that can't be altered back to original with the turn of a wrench. Changing the angle of the fork is out. Shortening a couple of tubes by an inch or 3 would give me a more comfy feel, but if it won't help the twitch, I can get used to it if I can keep the bike original.

Keith Wilson
06-23-2013, 12:18 PM
Less fork rake, or offset (that forward bend in the fork) for a given head angle and wheel size gives you more trail. Trail is the distance between the tire's contact patch and the point at which the steering axis intersects the ground. Generally more trail = less twitchy steering, albeit with somewhat reduced maneuverability. Two possibilities: bend the fork a little straighter, or replace it with one that has less rake. Switching forks isn't hard if you can find one that's the right size.

Another possible reason for a twitchy feel might be the very long bars, hence very light steering effort? Nah, maybe not. That would just be something you'd have to get used to. Can you rotate the bars a bit further forward? I can't tell from the picture.

Here's a more complete discussion of two wheel vehicle steering geometry. (Link (https://en.wikipedia.org/wiki/Bicycle_and_motorcycle_geometry))

A picture showing what I meant in the first paragraph:

https://upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Bicycle_dimensions.svg/563px-Bicycle_dimensions.svg.png

Garret
06-23-2013, 12:31 PM
Where else would you go for bicycle advice besides the WBF?

Ain't this place great?

My limited experience with recumbents says that it's more getting used to it than anything. I rode one with the bars under the seat & it took me forever to get the hang of it.

Those who are worried about being seen can put up a whip with a flag on it. Maybe a nice burgee?

LeeG
06-23-2013, 12:38 PM
$.02 it's twitchy also because there's very little weight on the front wheel.

reddog
06-23-2013, 02:49 PM
SchoonerRat, this is one of my rides:
http://i426.photobucket.com/albums/pp346/killick/Bents/DPSCamera_0029.jpg

When I first started riding it I fell off numerous times. I found the steering twitchy and the balance weird. I found the steering takes a light touch. A small input yields large results thus the steering tends to be twitchy. It's a matter of practise. Starting is never pretty, I tend to wobble until I get some headway on then it smoothes out. Also when peddling recumbents don't respond well to stomping. Try concentrating on spinning circles and the ride will smooth out noticeably. Finally, I find the balance is weird being more in the arse area. Good practise for core strengthening. Keep at it and your technique will improve and you'll be flying.

Earl

Flying Orca
06-23-2013, 03:24 PM
Earl, I don't think we got onto the topic when we met, but I ride a RANS Rocket... with the same bag, even.

SchoonerRat
06-23-2013, 04:58 PM
Where else would you go for bicycle advice besides the WBF?

Ain't this place great?

My limited experience with recumbents says that it's more getting used to it than anything. I rode one with the bars under the seat & it took me forever to get the hang of it.

Those who are worried about being seen can put up a whip with a flag on it. Maybe a nice burgee?

WBF The Font of all Knowledge.

My buddy has a Ryan with underseat steering. Other than giving him easier access for scratching his butt, I don't see it. This bike was his wife's. A bad hip keeps her from riding.

The handlebars are just a bent T that fits into the straight tube that connects them to the fork. I can adjust the length of the straight tube; and I can slide the center of the T in the handlebars in and out of the straight tube, both adjustments moving the grips higher and closer to the rider (or versa visa) at the same time. I'm bottomed out on both of the adjustments but I think I'm happy enough that I don't need to cut any tubes to go further.

I haven't fallen over yet, but I have managed to look pretty silly in front of a covey of young lovelies. Starting from a dead stop seems to be the easiest way to generate chuckles from bystanders, but the mere sight of this contraption does a pretty good job on its own.

Practice seems to be the answer to the twitches. First time out I was lucky to keep her inside the bike lane. This morning, with a lot of concentration, I was able to ride a white line for brief periods of time.

Definitely gonna go with the whip and flag before venturing into traffic. I was thinking either a flag proudly declaring that "My Other Bike is a Schooner" or "It's More Fun Lying Down".

This is the ultimate geezercycle. None of my worn out and pain ridden joints seems to be adversely affected. I need to rebuild a lot of muscles that were torn down a long time ago, but I can already feel that happening.

SchoonerRat
06-23-2013, 05:07 PM
Earl, I don't think we got onto the topic when we met, but I ride a RANS Rocket... with the same bag, even.

I guess if you're gonna go to a wooden boat forum to talk recumbent bikes; it's only natural to go to an aircraft company to build your bike. I can find no fault with the workmanship on my Tailwind. It feels rock solid but the frame seems to have just enough give to soften the ride a bit.

Keith Wilson
06-23-2013, 05:36 PM
The more I read the more I think that there's nothing wrong with it that a couple of weeks practice won't fix. "If it ain't broke . . ."

Weight on the front wheel doesn't have much to do with it either. The one I built had geometry more or less like this and it wasn't twitchy in the slightest.

http://www.legslarry.beerdrinkers.co.uk/images/mags/large/Avatar01.jpg

I kind of like the under-seat steering; it was weird at first, but you get used to it very quickly. The major disadvantage is that there's not much airflow over your armpits, and they get seriously sweaty.

Here's a larger picture of a Tailwind (with an ugly boat in the background). I can see now there's nothing you can do with the handlebars that doesn't involve a hacksaw or a torch.

http://laytek.net/bentbiker/wp-content/uploads/2008/04/Tailwind1.jpg

reddog
06-23-2013, 06:15 PM
Earl, I don't think we got onto the topic when we met, but I ride a RANS Rocket... with the same bag, even.

Ha,ha that is so cool. The V-Rex is a great ride, very comfortable. From all reports it can climb fairly well, with the proper technique and fitness level. I also have a bent trike which is a blast to ride and no worries about twitchy steering or falling off. :D

Earl

SchoonerRat
07-01-2013, 08:56 AM
Time in the seat is the answer. Every time out I feel more comfy on the recumbent. I'm really getting to love this bike. There are lots of bad roads and R/R tracks around the hood here. The Tailwind just eats 'em up. Just a couple of negative comments on the recumbent. When beating into a stiff sou'wester, you can't hunch over the handlebars to reduce your windage, and you can't drop your head to look through your armpit for traffic behind you. The latter problem is easily handled by mirrors, and the former I'll just learn to live with.

I'm trying to work myself up to a 15 mile crosstown trek. The 15 miles are doable now, but the route includes a couple of fairly major bridges (and a number of smaller ones). Recently rediscovered muscles are not yet up for the task. The local park includes a bike path that's about a mile long and includes a nice sized practice bridge. I haven't needed the lowest of my low gears since my first attempt, another week and I might be ready to tackle its big brothers.

reddog
07-01-2013, 08:12 PM
Time in the seat is the answer. Every time out I feel more comfy on the recumbent. I'm really getting to love this bike. There are lots of bad roads and R/R tracks around the hood here. The Tailwind just eats 'em up. Just a couple of negative comments on the recumbent. When beating into a stiff sou'wester, you can't hunch over the handlebars to reduce your windage, and you can't drop your head to look through your armpit for traffic behind you. The latter problem is easily handled by mirrors, and the former I'll just learn to live with.

I'm trying to work myself up to a 15 mile crosstown trek. The 15 miles are doable now, but the route includes a couple of fairly major bridges (and a number of smaller ones). Recently rediscovered muscles are not yet up for the task. The local park includes a bike path that's about a mile long and includes a nice sized practice bridge. I haven't needed the lowest of my low gears since my first attempt, another week and I might be ready to tackle its big brothers.

Definitely uses a different muscle group, especially climbing. By all reports the best climbing bents have a fairly upright seat with a 'closed' cycling position. I changed out both the rear cassette and front chainrings on the V Rex to help with the short but steep hills we have here. Keep at it man!

Earl

SchoonerRat
08-10-2013, 09:08 PM
Thanks for all of the wisdom and encouragement. This bike has just made the transition from really cool toy to basic transportation. "Practice makes perfect" was indeed the answer. It took about 25 miles of riding before I felt comfortable enough to venture out into traffic. Traffic, around here, is Mack trucks and freight trains. Even the Hummers have feelings of inadequacy.

I'm being much more careful with R/R tracks since I got eaten by one. I'm certain that if I'd been on an upright, there would have been a significant amount of pain involved. As it was, when I realized I was going down I put down my left foot, put my weight on it and stood up, letting the bike spin out under my raised right foot. When the dust cleared, I was standing next to the front wheel, handlebars in hand, looking over the rear wheel, facing in the direction I was intending to travel. I now have a much better idea of what is too shallow an angle to cross these things at.

Now that I have a couple hundred miles logged on this thing I have one question that still needs to be answered. Why in the world does anybody still ride an upright bicycle? There is no aching back from being hunched over the handlebars on a bent. There is no stiff neck from looking up from the hunched over position. no "Atomic Wedgie"! You've got a comfortable seat with excellent back support, and if you do fall, you don't fall far.

I love this bike.

PeterSibley
08-10-2013, 09:33 PM
Smaller wheels have very little to do with it. "Twitchiness" is almost entirely a function of steering geometry. You can build a recumbent twitchy or very stable, irrespective of wheel size. Trust me on this one; I'm a mechanical engineer who worked in a bike shop for quite a while, and I've build a couple of very odd bikes myself, including a long-wheelbase recumbent in 1981 - when driving a purple metalflake Lamborghini would have attracted less attention. FWIW, the one I built had a 16" front wheel and tracked like it was on rails. Unfortunately, you can't change steering geometry without bending or cutting metal. If it's not just a matter of getting used to it, a little less fork rake might improve things.

As far as safety, the only way a competently-designed recumbent is more dangerous is because it's less visible to cars. Their huge safety advantage is that falling 18" is far less likely to cause injury than falling six feet.

Bending and cutting metal is easy .

Here's my next build .

http://www.ab-bike.com/image/photo_azub-bike-azub_269.jpg

MiddleAgesMan
08-10-2013, 10:51 PM
https://upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Bicycle_dimensions.svg/563px-Bicycle_dimensions.svg.png

I'm surprised the "trail" on the OP's new bike hasn't been mentioned. It's obvious from the two pictures that there is no trail. His front wheel contacts the ground out in front of the projected fork angle. Seems to me that would be a major factor in twitchiness.

Stiletto
08-10-2013, 11:42 PM
Bending and cutting metal is easy .

Here's my next build .

It looks heavy, what will it weigh?

pila
08-10-2013, 11:43 PM
X2, or is it X3 ? on too much rake....or caster...

SchoonerRat
08-10-2013, 11:49 PM
I'm surprised the "trail" on the OP's new bike hasn't been mentioned. It's obvious from the two pictures that there is no trail. His front wheel contacts the ground out in front of the projected fork angle. Seems to me that would be a major factor in twitchiness.

Just a bit of an optical delusion in the pics. I checked when Kieth first posted. I didn't actually put a tape on it, but there is about 2" of trail. I suspect that the long wheelbase also contributes some to directional stability.

The twitch was all me. The riding experience on this bike is so different from an upright that it took some getting used to. You can't balance by bending at the waist, and the tiller effect on the steering was a completely new experience on a bike. My muscle memory needed a pretty complete retraining.

The twitch is gone. I still get a little wobbly when pumping hard uphill in low gear (damn this thing has some low gearing)! Once again, I don't think I can blame the bike, cuz that is also getting better with time in the seat. I'm finding this bike to be pretty flawless in design and construction.

PeterSibley
08-10-2013, 11:57 PM
[QUOTE=PeterSibley;3869997]Bending and cutting metal is easy .

Here's my next build .

It looks heavy, what will it weigh?

It WILL be heavy, about the same as my mountain bike ... which will be supplying most of the components. If I was equipped to weld aluminium it would be 6 or so pound lighter... but I'm not.

edited to add, it will also be quite small so not as heavy as the photo suggests.

skipper68
08-11-2013, 01:10 AM
First off, thank you.
I thought the OP was a commercial for Viagra! :D
Originally Posted by Gerarddm
I think recumbents are dangerous as hell.
I think bleached blonds with big knockers are dangerous as hell. I think mescal is dangerous as hell. And don't get me started on chocolate.

Are your fears as rational as mine? Care to expound a bit?
I thought the INCUMBENTS were the true danger! ;)

SchoonerRat
08-11-2013, 10:37 AM
First off, thank you.
I thought the OP was a commercial for Viagra! :D
I thought the INCUMBENTS were the true danger! ;)

First off, you're welcome. (what am I being thanked for?)

Sorry Skipper, I don't see the Viagra connection. This bike doesn't seem to ever go limp, and I haven't had a need to perform for years.

That INCUMBENTS crack would have gotten a pretty good chuckle from me a month and a half ago, but I'm afraid you were just a bit slow on the uptake. You've gone way beyond the statute of limitations on this one. Sorry, not even a grin from me.

wardd
08-11-2013, 10:51 AM
i just fell off my bike, it hasn't come back fast enough

SchoonerRat
08-11-2013, 11:18 AM
i just fell off my bike, it hasn't come back fast enough

OUCH!!!

How far did you fall? From a "step ladder" (upright bike)?
Trying to get back into cycling after a long layoff?
Able to get "back on the horse" after the fall?
What was your gotcha?
Any serious damage to your bike (or you)?

I hope "All the King's horses and all the King's men" aren't just standing around scratching their heads!

wardd
08-11-2013, 11:46 AM
OUCH!!!

How far did you fall? From a "step ladder" (upright bike)?
Trying to get back into cycling after a long layoff?
Able to get "back on the horse" after the fall?
What was your gotcha?
Any serious damage to your bike (or you)?

I hope "All the King's horses and all the King's men" aren't just standing around scratching their heads!

it's a cross trainer 700c wheels

it's stiff joints


no damage to the bike i'm sore as h

when i was in my 40's i rode about 200 miles a week, kinda miss it

when i recuperate i'll try again

SchoonerRat
08-11-2013, 02:40 PM
it's a cross trainer 700c wheels

it's stiff joints


no damage to the bike i'm sore as h

when i was in my 40's i rode about 200 miles a week, kinda miss it

when i recuperate i'll try again

Stiff joints...not so bad. I'm sore as h from riding, and I haven't fallen.

200 miles a week. Damn. I think I'd pass out if I tried 200 a week in a car. I did almost 20 yesterday. My longest yet. Calves and thighs are screaming bloody murder. Back is a little stiff, just a notch worse than normal. Getting a little complaining from my good knee - my bad knee is good. And I'm feeling what I hope isn't the first sign of a bum hip. I might go for a short little cruise this evening, just so my bike doesn't think I've forgotten about her, but I'm taking the day off.

On the plus side, the calf and thigh thing is a good hurt. I can feel my heart getting stronger. All of that extra LA smog that's getting pumped through my lungs is doing them a world of good. I've had to pull up a couple of notches on my belt to accommodate the loss of about 20 lbs.. I'm going in for my 3,000 mile checkup next weekend, and I expect to beat down my score on the sphygomomanometer by a few points.

Exercise is good for you. You can quote me on that!

wardd
08-11-2013, 05:30 PM
it's arthritis and just getting out of the hospital a few weeks ago

when i did ride like that it was painful to walk any great distance, my muscles became conditioned for a circular motion not walking