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  • Recumbent Bicycle Project

    One of the part-time instructors at the school is interested in recumbent bicycles, and he approached me about helping him build one from an old sketch that was in Popular Science (?) years ago. With several donor bikes, a little scrounging, and a bit of TIG-welding and machining, this is the result:



    We've added a chain support, brakes, a shifter, and a safety flag since the picture was taken. He's ridden it several miles in vacant parking lots to get used to it. It's a bit long at 97 inches overall, and a bit heavy at 45 pounds, but he's only spent $40 on the project.

    It was really supposed to look like this, but we made a few mods.

    http://www.rqriley.com/imagespln/xr2-1.jpg

    Roger
    Last edited by winchman; 12-07-2007, 04:57 AM.
    Any products mentioned in my posts have been endorsed by their manufacturer.

  • #2
    cool... I like it.

    Comment


    • #3
      I see dead people ---- esp. in a head on collision, first your gonna rack the twins and if thats not enough to add insult to injury youll be wearing the steering stem 3 to 4 inches inside of your forehead, Winchman I think your cool but im giving this one a thumbs down, I also think it needs to be printed with Evans disclaimer underneath it

      Lets have fun out there -- but for the love of god give a guy a fighting chance

      Comment


      • #4
        I have a real recumbent (he he), and I tell you it was wild when I first got it few years back. I got chased by girls (believe me very unlikely under any circumstances), I got chased by teens in truck, I have never been so famous.

        I nearly got nailed by this guy waiting by the side of the road. He was next to a large appartment building but not really near any useful exits, he might have been waiting at the stop sign just ahead... I came out into the oncoming lane because something didn't seem right, next thing, he steams right past me going as fast as he can in reverse without even rotating his head from the dead straight ahead postion. People don't see you in these things. And mine is bright yellow. Also, mine is right twitchy. I thought it would be at least as stable as a regular bike, but no such luck, I'd rather ride a unicycle

        That said, I think that is a great project!! Lots of interesting plans over at atomiczombie, and there is a nice wood model online also.

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        • #5
          Pedaling effort

          Do you lose the advantage of using your weight to push the pedals down with these bikes. If so, I can't see any gain that offset that loss. what am I missing?

          Comment


          • #6
            Originally posted by jstinem
            Do you lose the advantage of using your weight to push the pedals down with these bikes. If so, I can't see any gain that offset that loss. what am I missing?
            Not if you stand up and pedal.
            Jonathan P.

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            • #7
              I ride a Rotator Pursuit, sort of like the design pictured. Mine has
              a mid drive with a six cog cassette under the seat and a 9 cog cassette
              on the rear wheel and has 54 'speeds' not all different but the real
              advantage is the drive ratio is 7:1 (gears from 22 to 144) compared
              to regular bike ratios in the 4:1 range (30-110 give or take). Recumbents
              are always a bit to a lot more squirrelly than standard bikes but a few
              hundred miles on the bike takes care of most of this. Generally speaking
              the bent is safer for the rider than regular bikes, since you are closer to
              the road/ground and kinetic energy of impact is significantly less in a
              fall, and it is impossible to do a header over the bars.
              Steve

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              • #8
                winchman their is a yahoo group dedicated to recumbent bikes -- called GETBENT
                I have been thinking about building one for one of my grand son's.
                They seam to have some good plans.
                snoopy

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                • #9
                  Originally posted by jstinem
                  Do you lose the advantage of using your weight to push the pedals down with these bikes. If so, I can't see any gain that offset that loss. what am I missing?


                  Its claimed that you can actually "out pressure" a typical bike because your not limited to just your wieght above the wheels and can utilize your backrest therefore the push-power is only limited to what your legs can deliver, however -- its not how it works in the real world, regular bikes have your feet attached to the pedals therefore are not just limited to the riders weight, by pulling up on the rear pedal while pushing on the front you can now add all your weight plus the amount your pulling up with, they are as powerfull as all the different muscle groups that are powering them , and i might add its much better to rely on many muscle groups as if your just counting on one you will toast them very fast... recumbants are slow and very poor aerodynamically.

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                  • #10
                    Since you can walk, you can pick up your body mass with each leg at least.
                    So You have two x weight at least to press on the pedals with both feet. With standing over the pedals you can only push down 1x or you lift yourself.

                    Some of us, can pick up twice body mass. (okay, not anymore) See a young kid squatting with weights and you will see.. a 160lb kid pressing 400lbs.

                    I was clocked at 35mph with UT's funny bicycle. Older brother was a teacher there and brought it home. Not sure how fast I could have went. Less air to break too. My hair was flopping in the wind, the spokes were humming.

                    Who posted the 120mph bicycle? it had a car with a sail breaking wind for him.
                    Neat project, but like someone said, the onlookers and chasers to look are hazardous.
                    Excuse me, I farted.

                    Comment


                    • #11
                      I share your concerns about the safety of the design, and I certainly don't want to ride it myself for those and other reasons. I no longer ride my regular bike on the open road or even city streets, just around the subdivision or on vacant parking lots.

                      I was mostly just the fabricator, with some input on how to accomplish what he wanted to do. It was a good project in that respect. He had built one himself several years ago that was quite a bit heavier. The seating position was not as low, and it had the traditional steering setup. This one is much better than that one, especially in the welding.

                      I make no endorsements or apologies for the design.

                      Roger
                      Any products mentioned in my posts have been endorsed by their manufacturer.

                      Comment


                      • #12
                        Originally posted by sch
                        and it is impossible to do a header over the bars.


                        If the bike looks anything like the one pictured you would be wishing for the most minute possibility in the impossible... Crashing is an art --- iv been in more than id like to recall, Having cat like reflexes while in mid-air is a blessing and something you dont take for granted, removing all the possibilities of how its going to go down by being "locked in" to a death trap is a recipe for disaster --- actually having protrusions in from of you that will kill you is just plain stupid...

                        Have we learned nothing about the cars in the 50's that had massive chrome bullets in the center of the steering wheel or does someone need to dig up some pics?

                        The reason why im still tearing it up at my age is because Iv recognized along time ago that crashing is a part of riding, you want to be around you got to know how to do both... Not cocky, it could catch me tomorrow, I just realize I need all the help i can get...

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                        • #13
                          Recumbent??

                          Geez, I knew a few guys in college with these, then later in life engineers and other various odd individuals with them.

                          In my experience people that ride these are a little different and not in a particularly interesting way, it's more that they're a bit strange.

                          Comment


                          • #14
                            Bents seem to be ridden by old hippy types around here. strangely if there are a few 'normal' bikes and a bent anywhere, I'm the one most people assume to be riding the bent, must be because I normally wear sandles, cutoffs, tee shirt and have a foot long ponytail.

                            Bents have more effective power transfer than a regular bike because you have the seatback to provide leverage, with regular bikes you tend to lift yourself off the saddle. clipless pedals help to an extent, but since your legs don't 'lift' as well as they push, you just move the power band up a small amount. I know if I carry a 20lb backpack, I move my max speed up a ways because of the extra weight I have to push against.

                            Some bents are pretty fast, I've had a few go past me like nothing when I'm going all out.

                            Ken.

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                            • #15
                              One thing that you cannot see in the picture might make a difference in a crash. The steering shaft between the upper headstock to the universal joint is very lightweight tubing, which I suspect will buckle before there's any major damage to the upper torso. The support for the upper headstock will bend forward without much resistance after that.

                              I don't see impalement as the major safety item. Not that I'd want to test it, though.

                              The big problem I see is limited maneuverability because of the long wheelbase. You simply cannot turn as quickly as you can with a shorter bike.

                              There's a handyman here in Thomasville who uses a recumbent as his work vehicle, and he tows a trailer with a stepladder and about fifty pounds of tools and supplies behind it. I'm told he's been doing it for several years.

                              John's a retired high school shop teacher, a private pilot, and a square dance instructor. He seems above average normal to me.

                              Roger
                              Last edited by winchman; 12-07-2007, 05:19 PM.
                              Any products mentioned in my posts have been endorsed by their manufacturer.

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