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  1. #1
    Senior Member
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    Falling off the seat

    Hi All,

    I have a 2006 Trek Pilot 2.1 with about 500 miles on it now. I've noticed that I slip forward on the seat and am constantly having to put myself back in position. While riding, the pressure is on my taint and not my sitbones. I'm new to cycling, so I thought I'd ask the question, what do I need to? The seat appears level, but I keep falling off. Any help is appreciated.

  2. #2
    Perma-Clyde (51)'s Avatar
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    There are two adjustment screws under the seat. Tilt it back a bit by loosening the rear one and tightening the front one. I had the same problem with my new seat, but after some adjusting I (and my taint) felt much better. Good luck! You may want to run your seat forward a bit as well so you are not stretching for your handlebars.
    http://www.trailerparkboys.org/forum...fault/beer.gif In wine there is wisdom, in beer there is freedom, in water there is bacteria. -Ben Franklin

  3. #3
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    It may be that the saddle is too far back.
    You can move the saddle forward on its rails.
    If you are very heavy there may be an issue with leverage on the rails. You can solve this by switching the style of seatpost from one with a laidback clamp to an inline clamp.

    Horizontal position also affects vertical height. If you adjust the saddle forward you may need to raise it a few mm but that is quite a subtle adjustment.

    The horizontal distance from saddle to pedals is determined in part, by the ratio of your upper leg/lower leg. I have a short femur/long lower leg so the saddle is all the way forward.

  4. #4
    your nightmare gal chipcom's Avatar
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    Quote Originally Posted by (51)
    You may want to run your seat forward a bit as well so you are not stretching for your handlebars.
    No, no, no no!!! Don't adjust your saddle forward or backward to compensate for reach. Your saddle fore/aft should be adjusted to get your legs in the proper position in relation to the pedal/pedal spindle. Once this is adjusted properly, you can mess with adjusting/swapping the stem to put the bars in the proper position relative to the saddle.

    Here's a decent diy fit adjustment tutorial from http://www.sbraweb.org/setup.htm:

    Saddle Adjustment

    When setting up your bike, first determine the proper saddle height and fore/aft position. Saddle height should be adjusted so that your leg is just slightly bent at the bottom of the pedal stroke. (If your hips rock when you pedal, your seat is too high.) An oft-quoted formula is that the distance from the top of the saddle to the pedal axle (with the crank fully extended) should be 1.09 times your inseam. Another formula (the "Lemond Method") states that the distance from the top of the saddle to the center of the bottom bracket should be 0.883 x inseam length. (Note: Inseam is NOT the same as trouser length. Measure from floor to pubic bone, without shoes, with feet 6-inches apart.) These formulas provide good starting points. But shoe/cleat thickness, foot size, pedaling style, and other factors also come into play. Probably the best approach is to raise the saddle in small increments until your hips just start to rock when you pedal, then lower it a couple of mm.

    Beginners often feel more secure with their saddle very low, allowing both feet to touch the ground when stopped and sitting on the saddle. This is much too low. A low saddle doesn't make full use of the leg muscles, and may cause pain in the front part of the knee. If your saddle is too low, try raising it a little at a time until you eventually reach the optimum height.

    Proper fore/aft adjustment should place the front of your knee over the pedal spindle when the crank is in the "3 o'clock" position. Riders who do a lot of seated climbing may prefer a position 1 or 2 cm behind the pedal spindle. It's best to have someone make these measurements for you using a plumb line while the bike is on a trainer. (Since saddle height, and fore/aft adjustments interact, remember to check both after adjusting either.)

    Make sure your saddle is perfectly level. If it's tilted downward even slightly, your arms will have to work continuously to keep your body from sliding forward. That can be tiring on a long ride.

    Handlebar Adjustment

    Once the saddle position is set, you can check the position of the handlebars. Racers like to have the bars at least 2 to 3 inches below the top of the saddle to get an aerodynamic position. Recreational riders often set the bars at the same height as the saddle for more comfort. Experiment to see what height you prefer. If the frame is too small, you may have trouble getting the bars high enough for comfort. A tall stem and/or a stem that rises upward can help. Remember to heed the minimum insertion line on quill type stems. On threadless systems, spacers can be moved from above to below the stem to raise the bars (assuming the steerer tube hasn't already been cut too short).

    After setting handlebar height, check the horizontal distance from the saddle to the bars. There are formulas and old wives tales about how to do this, but ultimately it comes down to what feels right for you. If you find yourself riding with your arms straight most of the time (no elbow bend), the bars are probably too low or too far forward. When the bars are positioned correctly, you should feel comfortable with your hands on the brake hoods and your arms bent at the elbow. Your torso should be angled forward about 45 degrees, and you should not feel cramped or overly stretched out. Try standing up on the pedals and see if the bar position still feels right.

    It's not uncommon for a new bike to come with an overly long stem. Don't be afraid to ask the shop to swap it for a shorter one if you feel too stretched out. DO NOT slide the saddle forward or back to compensate for an incorrect stem length. That will compromise your saddle position relative to the bottom bracket.

    Ideally, the stem extension should be about 90 to 120 mm (depending on frame size). If you end up needing a stem outside that range, the top tube may be the wrong size for you. If you're buying a new bike, you may want to consider a different model.

    The bottom part of the bars should either be parallel to the ground or angled slightly downward. The brake levers should be positioned so you can operate them easily whether your hands are on the brake hoods or on the drops. Normally, a straightedge placed along the bottom section of the drops should just touch the end of the brake lever. But don't be afraid to experiment with lever position if it doesn't feel right.

    Most riders spend a lot of time with their hands on the brake hoods. That's fine, but riding with your hands on the drops is more efficient, particularly when heading into the wind. If your bars are too low, it may not be comfortable to use the drops. Also, some folks with short fingers find it hard to brake or shift from the drops. Switching from "anatomic" to conventional drop bars (if you can find them these days) may help.

    General

    It's normal to feel a few aches and pains on the first few spring rides. But if pain is persistent or severe, it could be due to improper setup. A stiff neck, sore back, or painful shoulder may be helped by raising the handlebars. As you become more flexible, you may want to gradually lower the bars to achieve better aerodynamics.

    If you have an indoor "trainer" that attaches to your bike, you can use it to evaluate your setup. Just make sure the bike is perfectly level. (You may need to put a board under the front wheel.) A half hour on the trainer will often pinpoint fit problems that you wouldn't easily notice on the road.

    The information above will get you in the ballpark. Don't be afraid to experiment. It's best to adjust one thing at a time, and do it in small increments (e.g., don't change seat height by more than 1/8 inch at a time). Then take a long ride to evaluate the changes. When you get everything "dialed in," you'll know it!

    In summary, small adjustments can make a big difference in comfort and efficiency. Saddle, stem, and handlebar adjustments can often compensate for SLIGHTLY incorrect frame dimensions. But starting with a frame that's perfectly matched to you and your riding style is definitely the way to go.

    © Art Harris, 2002
    Last edited by chipcom; 12-05-06 at 06:27 AM.
    "Let us hope our weapons are never needed --but do not forget what the common people knew when they demanded the Bill of Rights: An armed citizenry is the first defense, the best defense, and the final defense against tyranny. If guns are outlawed, only the government will have guns. Only the police, the secret police, the military, the hired servants of our rulers. Only the government -- and a few outlaws. I intend to be among the outlaws" - Edward Abbey

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