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Old 07-07-08, 08:18 AM
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Making it fit

Your bike shop staff should be doing the initial adjustment for ‘fit’ on your bike, but if you’ve purchased a secondhand bike or are merely interested in what it’s all about, here are the basics of it, in simple terms.

Before we start let’s check to be sure you’re not making a big mistake. You’re not clinging to that silly old idea about needing to be able to touch the ground on both sides whilst sitting on the seat (saddle) are you? That a silliness we used to hear, from folk who know little and say much, and it’s just plain wrong. We don’t leave our bums on the saddle when the bike comes to a stop! Instead, we come forward off the saddle as the bike comes to rest, and stand with feet astride the bar. If that saddle is so low that you can stand up when astride it, you won’t be able to have the bike adjusted properly for comfortable and efficient riding.

That leads into the first couple of things to be attended to.

Bar height

It won’t be an issue with step-through (ladies) bikes of course, but if that bike frame has a top tube you need to have clearance when standing astride it. For comfort and safety you should be aiming at a minimum of one inch (25mm) of clearance between crotch and bar, when you’re standing astride and off the saddle. If you don’t have that then perhaps look for a bike with a smaller or differently shaped frame.

Some (probably even many) road bike riders do ride with less 'top bar ' clearance than that, in order to have a bike with horizontal top bar and which still 'fits' their particular leg and torso lengths. If you are a newcomer though, or just plain not comfortable with the top bar cramping up the tackle, there are plenty of bike alternatives to explore. A bike with a sloping rather than horizontal top bar will give you better clearance.

Saddle height

If the saddle is too low your legs will be cramped up, you’ll be uncomfortable when riding, and you won’t be able to put enough power into the pedalling. If the seat is too high you’ll need to stretch to reach the bottom of the pedal stroke, again leading to discomfort and inefficiency. Long term, you’ll likely develop injuries or problems if the saddle is too low or high. So let’s get it right.

Have a friend watch you as you ride. The ‘shaft’ of the pedal should be under the ball of your foot, rather than the arch, as you ride and what you are aiming at is a saddle height which sees your leg extended but not ‘locked out’ at the bottom of the pedal stroke. Adjust the saddle up and down in accordance with the feedback from the person watching. When you get it ‘right’ there’ll be only a slight bend behind the knee when the pedal is fully down, and you won’t feel that you’re rocking at the hips or stetching the foot to get down there.

Got all that? Not really complicated, is it? We’re half way there so lets look at the rest of the ‘bike fit’ adjustments.

Saddle position

Saddle height is important, but the saddle also needs to be in the correct ‘position’ in relation to the pedal crank. If it isn’t we risk developing back and leg problems. Fortunately, it’s quite easy to get right.

Sit astride the bike and have somebody help hold the bike upright. Then, again with foot on the pedal correctly and the pedal crank under the ball of the foot, rotate the pedals until yo have them at the “3 o’clock/9 o’clock” position. Your knee should be directly above the pedal shaft on that front pedal. If it isn’t, adjust the seat forwards or backwards until you get that right.

If you find that a wee bit difficult to judge tie a weight to a bit of string and have your helper hold the end just at the bottom edge of your kneecap to have the weight hanging down (with your feet at that 3/9 position of course). That makeshift plumb bob should bisect the pedal shaft as it hangs.

Handlebar height and reach

Finish off by adjusting the handlebars to where you need them to be. Height will be determined by the position you feel most comfortable riding in. Adjust them up or down to where you want them, and then check the ‘reach’. When riding in your preferred position, your arms should be extended but not ‘locked out’. You need a bit of bend at the elbows to ensure that you have good control while riding, but not too much to have you cramped up. Adjust the handlebars forward or backward as necessary. You shouldn’t need to be sliding forward on the saddle to have reach or control.
Handlebar height and reach are adjustments for which the governing principle is YOUR COMFORT. Adjust them to where you need them.

The Saddle

Forgot about that, didn’t we? Obviously, if we’re not gonna be sitting our bums on the right spot on the saddle all the other stuff is gonna be mucked up a bit!

Never mind. You’re reading this through before you start fiddling with stuff, aren’t you? Getting the bike’s ‘fit’ right for you is really all about getting a good balance between those simple principles outlined above. If you’re doing it yourself, rather than have a bike shop do it for you, you’ll probably end up fiddling a bit and re-adjusting stuff. Get the seat position feeling right and then finding you’re riding a bit higher or lower than you thought you were gonna, so that puts the seat position back feeling a bit wrong. That sort of thing. Won’t take too much effort to get it right, that’s for sure! Right enough, anyway.

Putting your bum on the saddle right is easy. See those wide pads? They’re for your bum bones. That’s all there is to it. Your bum bones are really called your ‘sit bones’, and those pads are made for them. They’re the only place you put your bum bones, because putting those anywhere else ends up hurting, one way or another. The long bit at the front is there for control, not comfort. Inside of your leg keeps hold of the bike when you’re leaning over going around corners. (I never thought about that when I was a young fella. I soon figured it out after coming here, anyway.
Ladies saddles are usually a bit wider than gentlemen’s saddles. That’s no slight on their figures, though, because ladies ladies’ sit bones aren’t in the same spot. Gender doesn’t really make any difference. We all need to make sure we have a saddle which fits our sit bones.

A saddle which fits us is probably about the most important thing of all. Doesn’t matter how good the bike might be otherwise. If the saddle doesn’t fit it’s a crappy bike, because your bum hurts!

Last edited by Catweazle; 07-09-08 at 07:04 AM.
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