Buying the right size road bicycle on the first try
In addition to finding the perfect deal on your bicycle its important to buy a bicycle that is the correct size for your body. If the bike is too big or too small for you it does not matter how great a deal might be - the bike will simply beat you up too much. Within some small margin it may be possible to move the seat and/or bars up and down if the difference in the frame is an inch or two but even this is not ideal. Bicycles are like mens suits and generally are manufactured in one of three types: mass produced to specific size brackets, produced to fit a wider range of sizes and/or be adjustable, and custom tailored to order. Just like with a suit, every body is unique and will look/function best in an expensive custom tailored work of art. However as you are just starting out in cycling and probably buying your first used bicycle from Sprocket app or mass manufactured bicycle from your local bike shop, you will be picking from pre-set sizes. As of the 70's adult road bicycles have been manufactured in more or less standardized international metric size increments of ~47-63cm. So to ballpark its pretty easy to narrow down the frames that will work for your body by googling the following chart Feet+Inches/Centimeters Frame Sizes 4`10”-5`0”148-152 cm 47-48 cm XXS 5`0″-5`3″ 152-160 cm 49-50 cm XS 5`3″-5`6″ 160-168 cm 51-52-53 cm S 5`6″-5`9″ 168-175 cm 54-55 cm M 5`9″-6`0″ 175-183 cm 56-57-58 cm L 6`0″-6`3″ 183-191 cm 58-59-60 cm XL 6`3″-6`6″ 191-198 cm 61-62-63 cm XXL Frame shapes and geometry may vary, but in general the "frame size" is measured the same way. If you find a bicycle for sale on Sprocket app, a garage sale or your local swap meet simply take a roll-up ruler and measure from the center of the bottom bracket axle along the seat tube to the center of the join where the seat tube and top tubes intersect. If the top tube is at a sloping angle, measure to the center of where the top tube would have been if it went straight and met an imaginary continuing seat tube. It is important to note that frames also come in half centimeter increments and once you try out a few you may find that one of those works even better for your particular body. For example most of the bikes that I have as 57.5cm feel better than 57cm. You should be able to stand over your bicycle frame so that the top tube passes under neath your groin with both feet planted on the ground, but not in an uncomfortable way. It also bears mentioning that if it does not feel good when youre standing over it imagine the impact that would happen if you suddenly came forward off your saddle for any reason. When sitting on your saddle you should be able to reach the pedal platform at the bottom of its rotation with your knee slightly bent. There is not really an ideal formula for figuring out ideal seat height for making this feel right. You can always bring or ask your seller to bring the right tool for adjusting the saddle when you ride your bike. Once you buy your bike you will have to ride around and readjust the saddle over time to dial it in just right. The handlebars can also be adjusted to suit your riding style and body shape. The handle bars can be rotated up or down which may improve handling and comfort on longer rides. The stem can be replaced quite easily if its a quill/seven stem and you can also try inverting it upside down or right side up if its a threadless model. For some women it may be worth considering a shorter "stubby" style stem that brings the bars closer towards the saddle. The best place to go for all of these adjustments is of course your local bike shop! You can ofcourse get a bike fitting. However those cost money and if you bring the wrong size bike no fitting will help you get it dialed in. The ideal strategy when starting out is to use a sizing chart and buy a used bike that feels about right for cheap. Then ride and learn if it is your size or you need to try one taller or smaller and potentially sell the first. It is only when you learn your frame size for sure and start going on longer and more intense rides that it may be time to consider a bike fit. 7 Sprocket App Founder