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Streamlined Lunatic Fringe

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Recumbent bicycles
Published
1 August 2003
Last activity
15 August 2003
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Dogboy
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  1. "Jeff Wills" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    "Mark Leuck" <[email hidden]> wrote in message


    news:<rE0Ya.50992$cF.18738@rwcrnsc53>...

    Quoted message said:

    <snip>

    Quoted message said:


    I would think the slow speed of the climb wouldn't be enough for any


    gain by

    Quoted message said:
    Quoted message said:

    aerodynamics?

    It depends on what you mean by "slow speed", "climb", and "aerodynamics". There's a paper
    written by Daniel Kirchner in a 1985 issue of Bike Tech magazine titled "Aerodynamics versus
    weight". In it, he describes a method of calculating the relative value of reduced drag versus
    greater weight for various power levels. The formula for determining speed at any one instant
    has ten variables- to determine the duration of any ride requires specifying distance, slope,
    and any stops and starts.

    The author compares a conventional upright (25 lbs- 195 lbs with rider) with a faired trike (50
    lbs- 220 lbs with rider over a "commuting" route: a couple stops, gentle slopes, modest rider
    power (100 watts). In this simulation, the faired trike comes out 10% faster.

    It may be that in the "real world", streamliners can't use their speed to their advantage- they're
    just too fast on downhill slopes.

    For instance: I used the HPV speed simulation at
    recumbents.comHPV Simul.asp I used a rider power of 200 watts, a vehicle
    weight of 50 pounds, a rider weight of 170 pounds, a CdA of .055 (the Barracuda streamliner) and
    an altitude of 2,000 feet *and* a slope 5 percent. The calculations show that the vehicle is doing
    close to 85 miles per hour at the end of a 5 minute descent. The ascent tops out at 8 miles per
    hour. There's plenty of rides around here that allow an 8 mph uphill- but 85 mph going back down?
    *I* would be riding the brakes all the way.

    Jeff

    I was referring to uphill only but interesting data anyway

  2. Mark Leuck said:


    "Tom Sherman" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:


    S. Delaire \'Rotatorrecumbent\ said:


    we have a solid pro level bike club in town and hills as steep as 21% ,


    many

    Quoted message said:
    Quoted message said:

    tour riders come here to train. I haven't seen anyone make any major time on dogboy on any
    climbs Coyote is 45 pounds he usually stays right on their heels going up (a mind game he
    plays on


    them)

    Quoted message said:
    Quoted message said:

    and then coasts away on the other side. local guys all know his abilities which is why dogboy
    is so frustrated,


    no one

    Quoted message said:
    Quoted message said:

    to play with any more. Someday others will see and understand

    Speedy,

    I can certainly believe that a strong rider on a streamliner could stay with upright on
    reasonably steep grades (such as those on major highways), since the aerodynamic drag on an
    upright rider in a climbing position is very high. Going fast enough on a 45 pound bike on a 21%
    grade for aerodynamics to make a significant difference does not seem within the possibility of
    most (all?) riders, however.

    Tom Sherman - Quad Cities USA (Illinois side)

    I would think the slow speed of the climb wouldn't be enough for any gain by aerodynamics?

    I climb the short ~20% grade in town at about 4-5 mph on my Sunset. The aerodynamic drag at these
    speeds is negligible, so I would certainly be slower in a heavier Rotator Coyote. Short rolling
    hills and shallow grades would be a different matter entirely, where the Coyote would easily be 50%
    or more, faster overall.

    I would love to have the Coyote on one of the invitational rides in the rural areas just outside of
    greater Chicago.

    Tom Sherman - Quad Cities USA (Illinois side)

  3. Quoted message said:

    Many people who take up cycling recreationally do so for social reasons,

    Bill is right, streamliners are not as condusive to social interaction as an unfaired bike. I feel
    his point is probably one of the many drawbacks streamliners will have for alot of folks. Judging
    by the responses here in this group, that IS interested in recumbents but probably only represents
    .00001% of the biking population, it sounds like streamliners will continue to be a very hard sell
    indeed. Also, those downhill speed calculations aren't too far off the mark. Jeff said he would be
    riding the brakes all the way down. I did that and lost both front and rear Magura hydrolic brakes
    at 60 mph on a desent from 6000 ft. to Salton Sea. I had to throw the COYOTE down on a two lane hwy
    with quite a bit of semi truck traffic. Stupid me,....venting the brakes IS CRUCIAL !!!!!!

  4. Jeff Wills said:

    It depends on what you mean by "slow speed", "climb", and "aerodynamics".

    And by "mean" ;-)

    However, it's also worth noting that for distances as varied as the 37.75 miles of the Isle of Man
    Mountain Circuit, and the almost-but-not-quite 900 miles from Land's End to John O'Groats, Andy
    Wilkinson's faired Windcheetah was faster than the stick bikes. By about five minutes on the Island
    (over some bloke called "Boardman", who was alleged to be quite handy against the clock) and three
    hours for LE-JOG. Consider also Ymte Sybrandy's Paris - Amsterdam record which, according to my best
    attempts at research, is SEVEN hours faster than a group of three upright riders managed, over a
    distance of 540 km...

    Dave Larrington - legslarry.beerdrinkers.co.uklegslarry.beerdrinkers.co.uk
    ===========================================================
    Editor - British Human Power Club Newsletter
    bhpc.org.ukbhpc.org.uk
    ===========================================================

  5. Warren Beauchamp is always looking for fresh meat to slaughter at Northbrook, Tom. C'mon, do it!
    "Tom Sherman" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:


    S. Delaire \'Rotatorrecumbent\ said:


    Tom Perhaps that's true. Dogboy is "above average" in power and handling skills. But not a
    pro or


    paid

    Quoted message said:
    Quoted message said:

    cyclist. Smoothest person I've ever ridden with on a tandem. Bike is pretty damn fast too. Makes
    for a "hard to beat" combination. You would benefit from a good streamlined bike just as much as
    Dogboy


    does.

    Quoted message said:
    Quoted message said:

    That is if you like to be the first in on the local club rides, or pass


    pacelines,

    Quoted message said:
    Quoted message said:

    or scream down hills.....change Clark Kent into Superman Which I think, is his main point

    Speedy,

    I have been seriously considering getting a streamliner at some point (maybe a custom titanium
    alloy Sunset clone as a chassis built by someone such as you).

    However, I see one problem with such a bike - it would be too fast. Club rides would require no
    real effort and it would be impossible to ride with others unless they also were riding with a
    full fairing. Even my unfaired Sunset is too fast in some situations.

    If I get in a situation where I am regularly riding with uprights, I would consider a bike such as
    an EZ-1 SC. The speed handicap would make me work harder so I would become a better rider.

    Tom Sherman - Quad Cities USA (Illinois side)

  6. Bill Bushnell <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:
    Joseph Kochanowski said:

    One way that streamliners will become popular is if their speed on the road becomes
    breathtakingly fast.

    Speed may make streamliners popular with some people, but convenience, versatility,
    controllability, and sociability will be just as if not more important to most.


    I guess I am not like most other riders. I do not care about how sociable my bike is. I only care
    how well it works on real roads. Most of the commuting I do is alone. When I am riding with other
    riders, I prefer passing them anyway.All my other bike riding friends do most of their riding alone.
    I do not know anyone who mostly rides for social reasons in groups of other riders. This post
    started by asking if there will be more streamliners in the future. I think there will be more
    streamliners if someone just builds and sells them. Right now there is no place to get a good two
    wheel streamliner. I am not interested in turning this into a discussion about bent vs UCI approved
    and which one is better. I am very angry that there are few builders like me who own fast roadworthy
    streamliners and want better ones. I get really mad when I have to build and hoard a lot of
    streamliner junk by myself. I notice that when streamliner builders get together and exchange stuff
    like fairing moulds and used vehicles, that it gets more people riding streamliners. Another
    comparison between car and bike people suggests to me that bike people do not have the technical
    skills that car people
    do. While there are many car people who do extensive work on cars in their own homes, bike riders do
    not seem to like working as much on their own bikes. It seems to me that bike riders do not like
    to collect a lot of stuff like car collectors do. I know a lot of car collectors but no bike
    collectors. I seen to notice that a lot of bike riders are neo-luddites who abhor technology.
    Guys like Speedy Rotator are good bent builders as well as good car mechanics. Airplane
    afficionados usually like streamliners also. I usually do not have to explain the importance of
    areodynamics for fast speed to airplane people. Speed does make a big difference. When I showed
    up at a local time trial with an average bent nobody noticed. The next time when I had a fast
    streamliner and beat everyone, this got their attention. To a lot of bike riders "Winning is the
    only thing".

  7. I would love to ride a streamliner or velomobile, 2 or three wheeled. Unfortunately I don't have the
    time or technical skill to build one. The couple of velomobiles available are very rare and
    expensive and you pretty much have to take a trip to Europe to even try one. Craig

    [email hidden] (Joseph Kochanowski) wrote in message
    news:<[email hidden]>...

    Quoted message said:

    Bill Bushnell <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:
    Joseph Kochanowski said:

    One way that streamliners will become popular is if their speed on the road becomes
    breathtakingly fast.

    Speed may make streamliners popular with some people, but convenience, versatility,
    controllability, and sociability will be just as if not more important to most.


    I guess I am not like most other riders. I do not care about how sociable my bike is. I only care
    how well it works on real roads. Most of the commuting I do is alone. When I am riding with other
    riders, I prefer passing them anyway.All my other bike riding friends do most of their riding
    alone. I do not know anyone who mostly rides for social reasons in groups of other riders. This
    post started by asking if there will be more streamliners in the future. I think there will be
    more streamliners if someone just builds and sells them. Right now there is no place to get a good
    two wheel streamliner. I am not interested in turning this into a discussion about bent vs UCI
    approved and which one is better. I am very angry that there are few builders like me who own fast
    roadworthy streamliners and want better ones. I get really mad when I have to build and hoard a
    lot of streamliner junk by myself. I notice that when streamliner builders get together and
    exchange stuff like fairing moulds and used vehicles, that it gets more people riding
    streamliners. Another comparison between car and bike people suggests to me that bike people do
    not have the technical skills that car people
    do. While there are many car people who do extensive work on cars in their own homes, bike riders
    do not seem to like working as much on their own bikes. It seems to me that bike riders do not
    like to collect a lot of stuff like car collectors do. I know a lot of car collectors but no
    bike collectors. I seen to notice that a lot of bike riders are neo-luddites who abhor
    technology. Guys like Speedy Rotator are good bent builders as well as good car mechanics.
    Airplane afficionados usually like streamliners also. I usually do not have to explain the
    importance of areodynamics for fast speed to airplane people. Speed does make a big
    difference. When I showed up at a local time trial with an average bent nobody noticed. The
    next time when I had a fast streamliner and beat everyone, this got their attention. To a lot
    of bike riders "Winning is the only thing".

  8. Often these discussions point to uphill speed or downhill speed by someone who has already made up
    their mind on the subject but hasn't had the "hands on" experience A good streamliner often carries
    enough momentum to coast half way up the hill before the rider even needs to pedal. No way to know
    that unless you try it. There is air friction at 3 mph though a good streamlined bike wouldn't be
    going that slow. 50 pounds is a good weight for a full streamlined bike, even on climbs! Dogboy
    knows all this Joe Kochanoski knows the same Speedy has the knowledge because we have the bikes sure
    wish more people did too Speedy

    Gary Fritz said:
    (Jeff Wills) said:

    calculations show that the vehicle is doing close to 85 miles per hour at the end of a 5 minute
    descent. The ascent tops out at 8 miles per hour. There's plenty of rides around here that allow
    an 8 mph uphill- but 85 mph going back down? *I* would be riding the brakes all the way.

    And even if you are brave/crazy enough to scream downhill at 85mph, you're still at a disadvantage
    to somebody who can keep a higher sustained speed.

    Let's say we use those figures for a 1 mile climb followed by a 1 mile descent, and assume the
    average speed is actually half the maximum speed. In other words I'm assuming the uphill AND
    downhill runs start at 0mph and increase linearly to the maximum speed. (Or, more realistically,
    the uphill speed starts at the maximum and peters out to zero at the top!!) Not very precise, but
    close enough for discussion.

    Going uphill takes the streamliner 1 mile / 4mph = 0.25 hour = 15mins. On the downhill run it's 1
    mi / 42.5mph = 0.02353 hour = 1.41mins = 85 sec. So you go 2 miles in 16 mins 25 secs. Your
    *average* speed is only 7.31 mph, because you spend so little time going 85mph. That's the killer.

    Now let's say you have an upright rider who can stand on the pedals and maintain a decent speed
    uphill, but can only do 30mph on the downhill. Even if we assume he only averages 15mph downhill,
    it still only takes him 1 mi / 15mph = 0.0667 hour = 4 minutes to go downhill. If he can get
    uphill in anything under 12 mins 25 sec, he will beat the streamliner to the end of the downhill
    run. That's an average speed of 1 mi / 12.41 mins
    = 4.83 mph, or a max of 9.67 mph on the uphill stretch.

    So even though the streamliner's max downhill speed is 2.8x faster than the upright's, the upright
    only has to go 21% faster on the uphill run to beat the streamliner's time.

    Personally I think an upright cyclist beating a streamliner by 21% going uphill is a lot more
    likely than the streamliner going 85mph OR the upright cyclist going 30mph on the downhill.

    And that's assuming the poor guy in the streamliner doesn't die of heat stroke while he's churning
    away on the 15min uphill grind. :-)

    Gary

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  9. S. Delaire \'Rotatorrecumbent\ said:

    A good streamliner often carries enough momentum to coast half way up the hill before the rider
    even needs to pedal.

    If you're on rollers, sure. If you're on the kind of hills you usually find around here (Colorado,
    just east of the mountains) -- e.g. the 2mi uphill run from the local bike trail to my house, the
    last mile of which must be at least a 4-5% grade -- there ain't any momentum. The only coasting yer
    gonna do is backwards. :-)

    Gary

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