MOUNTAIN BIKE SIZING
Mountain biking is one of my favorite sports. I learned early that mountain bike sizing and the right bike is essential. I used to ride a recreational bike and when I moved up to a racing bike it was wonderful. Mountain bike sizing whether recreational or racing style is critical to fun and safety. Read on for more information about mountain bike sizing and how to get the right size bike for your needs. There will be basic steps, then it will get more specific.
IMPORTANT LENGTHS
When considering mountain bike sizing, there are a couple of different things that you want to measure. The distance between your inseam and your pedals is one imperative measurement in this process. That is the distance between your hips and the pedals, and if it is too long or too short it can be difficult to handle the bike and stay atop it properly.The distance between the seat and the bike handlebars is another important part of the mountain bike sizing. This is another distance that if not done properly can lead to an accident or serious discomfort or injury. The more appropriately sized the difference between the handlebars and the seat is, the better able you will be to handle your bike--especially during rough terrain. Too long of a distance to reach for the handlebars affects a rider’s ability to brake and shift and respond to rough or unsafe conditions.
Getting Help With Mountain Bike SizingIf you go to a store to purchase your bike, the salesman there should be able to help you understand the importance of the different measurements for mountain biking. Go to an actual bike shop, not a sporting goods store for a true mountain bike. In many cases, the distances can be altered to make you more safe and comfortable while atop the bike. At the same time, some bikes are just not going to be for you--no matter how visually appealing you may think they are. Mountain bike sizing is not a science, but it is important. Decide for yourself what feels the best for you in the end, even if the measurements tell you something else. Your comfort and safety are more closely related than you may think.
FRAME SIZE
Step 1 Measure your inseam. You should do this barefoot. Stand against the wall and put a book between you legs so it presses right up against your pelvic bone. Make a mark with a pencil on the wall along the top of the book. Measure the distance from the floor to the mark in centimeters. Step 2 Use your inseam measurement to get a rough idea of your road bike size. Multiply your inseam by .65. This will give you a good estimate of you road bike size for bikes measured center to center. Thus if your inseam is 86 cm, you will fit a 56cm road bike (86 x .65 = 55.9). Note that many road bikes are measured center to top. To determine how to fit these bikes, multiply your inseam by .67. Step 3 Subtract an additional 10cm and convert this measurement to inches to get your mountain bike frame size, roughly. Thus, if you fit a 56cm road bike (c-c), you will fit a 46cm - or an 18" - mountain bike. As a general guide, mountain bike sizes available are shown in the following table: Size XS Bike Size 14" - 15" Size S Bike Size 16" - 17" Size M Bike Size 18" - 19" Size L Bike Size 20" - 21" Size XL Bike Size 21" - 22"
SADDLE: TILT AND HEIGTH
TiltYou want your pelvis to be on a level surface. Many people tilt their saddle forward as it is more comfortable. Stock saddles are usually very hard and it is better to replace the saddle with a comfortable one, in which you can ride at a level surface. The closer you get to level, the easier it will be to find the correct fore-aft saddle position. Saddle Height For your saddle height, sit on your saddle with one leg hanging free. Be sure your hips are square. This means both facing forward. Your free hanging heel should touch the pedal with a straight leg. The pedal should be in line with your seat tube and at the bottom of its stroke. You want some bend in your knee. If your legs are straight it can create some discomfort on the saddle as your hips rock back and forth.
CRANK LENGTH
The leg length will determine the crank length. Findings have shown the correct length should be 18.5% of the distance from the top of your femur to the floor. The femur is your thigh bone and it attaches at the hip, which would be the top of your thigh.This is not a set in stone rule, but a general guideline. You also need to go by what gives you more power and comfort.
TUBE LENGTH
Consider top tube length very important. In many ways, this is the most important aspect of sizing a bike. Two 18" mountain bikes may have different length top tubes. Or a 54cm and an 56cm road bike may have the same length top tube. Given the same top tube length, the bigger bike may be more comfortable in that it will allow you to get the bars up a bit higher.Know that women have longer legs and shorter torsos than men. Unfortunately, most bikes are designed for men, and women often have a hard time finding a bike that will fit them well. Luckily, some manufacturers have begun to make women-specific models. Test ride some bikes once you have gotten a rough idea of what will fit you. This will help you determine what is most comfortable for you.
FORE-AFT SADDLE POSITION
Your fore-aft position, or the distance your seat is from the handlebars, determines how you are balanced on your bike.This will affect your pedal efficiency.1 Sit on your bike on a trainer or with someone holding the bike for you. 2 Rotate your pedals parallel to the ground. Drop a plumb line from your bent knee to the ball of the foot (where your foot clips into the pedal). You can use a string with a pencil tied to the end for your plumb line. 3 You should adjust your seat until the plum line and the ball of the foot are in a straight line. This gives you an efficient pedal stroke.
HANDLE BAR POSITION
Having your handlebar forward and low, in a racing position, allows you better aerodynamics and high speed control. It is also harder on your body. If you do long rides, such as in adventure racing, this is not the position for you. If you choose to have the bar closer to you and higher it will be more comfortable. You will sacrifice efficiency. If you are riding for recreation, this is great and very comfortable. A very efficient position is to have your bars a couple of inches lower than your seat. This is going to be personal preference and how much efficiency you would like to have. Handlebar width is not as critical on a mountain bike as a road bike, where aerodynamics are key. The main thing here is to find a comfortable position for yourself. Books
Do you still need information on mountain bike sizing? Todd Molloy teaches you how to be sized for your bike. He also covers how and where to test your bike, and where to buy it from. This is a nice addition as you definitely want to get the "right" bike. ARTICLES
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