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New bike - can't ride no-hands anymore?

  1. Dec 26, 2005 #1
    Just bought a new recumbent bicycle - full lawn chair type seat and pedals directly forward, with legs now horizontal. Tried no-hands riding, but failed repeadedly. The steering seems fine, just can't seem to balance this critter for some unkown reason, like i can on my mountain. The recumbent's steering geometry nearly replicates the mountain bike's (steer axis angle and trail), and handles just fine, so i'm genuinely stumped.
     
  2. jcsd
  3. Dec 26, 2005 #2
    Is the ride height lower or higher?

    Maybe it is because your centre of gravity is not low enough. It could also be you are in sitting position and therefore it will be harder to balance.
     
  4. Dec 26, 2005 #3

    Mk

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    Nice location nvidia17. How are the burgers?
     
  5. Dec 26, 2005 #4
    If you are not gonna post anything constructive, then don't post at all. Please.
     
  6. Dec 26, 2005 #5
    At first, try it when you are going really fast (but don't fall off!) and see if you can.... Far easier to balance that way....
     
  7. Dec 26, 2005 #6
    The seat height is about 20". Which lower than a regular bike.
    That's what I suspect, but why is that? I can walk beside the recumbent and steer it just fine, via frame tilting by holding on to the seat back (like a regular bike).
     
    Last edited: Dec 26, 2005
  8. Dec 26, 2005 #7
    Tried that, but same results. I can only ride about 20 feet or so, in a straight line, and even that feels dangerous.

    Again, the recumbent's handling and steering feels great, so I don't suspect design issues or malfunctions. It just feels like i'm learning to walk all over again,.. something missing. Just not the same results as my mountain bike.
     
  9. Dec 26, 2005 #8

    DaveC426913

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    Do the front forks bend *forward* near the bottom like on a regular bike?

    On a regular bike, one of the things that keeps the bike going straight is that the axis of rotation of the steering falls *behind* the axle by several inches. Also, the axis of rotation is tilted back at an angle.

    The upshot is that the bike has a lower centre of mass when going straight, and a turn requires effort put into raising it. Thus, deviation from straight path is discouraged.
     
  10. Dec 26, 2005 #9

    Astronuc

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    I believe DocToxyn rides a recumbent bike, so perhaps he can provide some insight.

    I thought they tended to be more stable, however, I prefer the conventional type.
     
  11. Dec 26, 2005 #10

    Bystander

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    Your moment about the "roll axis" is reduced. You're a tight rope walker without a balance pole, and, over you go.
     
  12. Dec 26, 2005 #11

    D H

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    I suspect the answer lies in the different rotational inertia of the mountain bike and recumbent. Mountain bikes have much larger tires than do recumbents. Those little recumbent tires don't build up nearly as much angular momentum as do the big knobby tires on a mountain bike.
     
  13. Dec 26, 2005 #12

    Q_Goest

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    On a recumbant bike, aren't you leaning back on a back rest? If you are, your upper torso are essentially locked to the bike, your torso goes where the bike goes. If you ride a regular bike, the bike can go from side to side a bit, but your torso stays essentially still. Your torso is the largest piece of inertia on the whole system. I'd suggest it has something to do with this.

    I think your torso is acting like a large mass that - on a regular bike - can act independantly of the wheels and allow for small, even rapid variations in direction whereas if your torso is locked to the bike, the entire mass of the bike is going in those same small, possibly rapid variations in direction.
     
  14. Dec 27, 2005 #13
    Yes. It is usually refered to as "rake" or "fork offset".

    I measured the steer tube (axis) angle at *59 degrees* and the trail at 1.5". As i stated before, I can walk beside the bike, while balancing and pushing it. It responds exactly like a regular upright bike, in that, when I tilt the frame, it responds by turning the front wheel in the leaned direction. Isn't this an indication of the presents of trail?
     
    Last edited: Dec 27, 2005
  15. Dec 27, 2005 #14
    Although not as well as my mountain bike, I can ride a kid's 20" BMX bike hands-free and it posses much smaller tires than the recumbent.
     
  16. Dec 27, 2005 #15
    Hummmm? hadn't thought of that. Very interesting! Could you please elaborate in greater detail?

    Come to think of it, on my mountain bike (riding no-hands), I balance by pivoting my hips laterally (which tilts the frame, so trail steers the bike). On the recumbent, my feet are parallel to the "roll axis", so I have no lateral leverage to CONTROL the roll axis. Hummm? does that sound plasable ?
     
    Last edited: Dec 27, 2005
  17. Dec 27, 2005 #16

    DocToxyn

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    Hey, DocToxyn here, confessed recumbent bike junkie. Congrats on the purchase, once you get used to it you'll never go back (OK some people do, they never give up the 'bent). I think a lot of the advice you've received here so far is probably true, the position of the body and ability to move around the bike is very different than what you're used to on an upright and therefore it may just take some getting used to. Most experienced riders say you need to put several hundred up to 1000 miles under your belt before the muscle groups required for 'bent riding are developed, even I you've ridden an upright for years. You'll get used to the balance issue well before this, but more muscle means more control and you may find it improves slowly over time. So you can see that there is a "learning/development curve" ahead of you (nothing to be intimidated by though).
    First tell me what bike you have - short wheel base, long wheel base, compact long wheel base, give me manufacturer and model as well. There are so many different configurations that then determine how stable they may be under hands free control. Once we know this, then we can start talking about bottom bracket to seat height ratio and length of wheel base and other steering and handling-related parameters Having said that, I know some people who can ride without hands on certain models, I can pull it off for a short distance on my RANS Rocket, but most choose not too. The other thing to think about is, what is your need to ride without hands? Is it just to grab some food on long rides, or shed a layer, or are you just trying it since you can do it on your MB? You may find that you don't miss it or need it, just sit back in that comfy seat and watch the world go by.
    If you're looking for more answers, advice or information, check out bentrideronline and their forums page, I post there also. Edit: These guys are having some "server issues" at the moment so the homepage is over a year old and the forum doesn't work. Hopefully they'll correct this soon.
     
    Last edited: Dec 27, 2005
  18. Dec 27, 2005 #17

    DaveC426913

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    Q_Goest has a good point: How does one actively balance on a recumbent? You have no weight to throw around.
     
  19. Dec 27, 2005 #18

    DocToxyn

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    It's not particularly hard, especially when you're moving and you get rotational forces from the wheels coming into play. However, even at very low speeds, 2-3 mph, one can still pilot these things fairly easily (again depending on the layout and geometry of the frame/parts). At low speeds, steering comes more into the picture as you are constantly twitching the bars to correct one's direction. It's also a very mental thing, you just have to commit to it and do it and the balance comes along with it. I know some people who have tried my bike and can't get it to go at all, I think most of it is fear.
     
  20. Dec 27, 2005 #19
    Who, specifically, can ride a recumbent "no-hands", with the ease of a mountain bike? And what model recumbent are you refering? I am riding a Rans Stratus XP.
    As I stated before, I can do for a very short distance too. However, I don't think 20 or 30 feet of turn-less riding proves much, except to establish that somethng IS different. Can you navigate around a city block? I'm not asking you to try, just curious if you feel you can.
     
  21. Dec 27, 2005 #20
    Your first sentence refers to using the "bars", so you are speaking from a typical "hands on" view point - that's outside the specific topic here, I believe.
     
    Last edited: Dec 27, 2005
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