....
Sizing. Bikes, like shoes and cardigans, come in different sizes. Sizes vary between brands so don't count on an 18” Brand X fitting the same as an 18” Brand Z. These are the key considerations: Stand-over, Saddle height, Reach.
Minimum Stand-Over Height. Standing with the bike between your legs it is essential that there is a decent gap between the underneath of you and the top-tube. It's simply the difference between your inside-leg measurement and the height of the top tube from the ground. To establish your Stand-over clearance simply stand astride the bike with the top tube under your crotch and with your feet flat on the floor, then grab the handlebar stem with one hand and the saddle with the other and lift the bike up as high as it will go. Try and keep it level and ask a bystander to measure how much gap you have under your wheels. On a street bike, racer or touring bike this might be as little as an inch (25mm), on a mountain bike we aim for no less than four inches (or 100mm). This procedure establishes the maximum frame size in that particular model and you can progress to..
Saddle height. “Sit on the saddle, place the flat of your foot on the pedal and adjust the height of the saddle until you can just straighten your leg. When pedalling the ball of the foot should be directly over the middle of the pedal and as a result your leg never fully straightens out”. It's the universal bike shop saddle height adjustment method. However, for a beginner this method will set the saddle way too high for comfort or confidence so it is the job of a good bike fitter to help the new cyclist find a compromise between a saddle height high enough for pedalling efficiency and a saddle height low enough to feel safe. Usually, after a few weeks of regular cycling our cyclist should have developed enough confidence to cope with a few centimetres of extra seat height. The saddle also has a few mm of fore and aft adjustment should you need it.
Reach. The distance from the saddle to the bars is called reach and it's every bit as crucial as saddle height to get right. Adjusting the handlebar stem up and down (or replacing it for one of a different length or height entirely) puts the bars where you want them. High for more control and a sense of safety in traffic, low for better aerodynamics and greater speed. Too close and you'll feel cramped, too far away and you'll feel too stretched out. At first it's hard to know how you are supposed feel on the bike but making a conscious effort to be aware of your position really is the key to many happy miles of cycling. Adjustments can be usually undertaken with a single tool, the folding multi Allen key tool. So universal are they that many companies make them and many make several versions. Get one and learn how to wield it.
From Cyclorama.
I'd better sort it before heading off for the weekend.
