What Is Inseam Size
Inseam size is often regarded as one of the most important factors when choosing a frame size. Inseam is simply the measurement from the floor to the highest possible crotch position measured in cm.
Measuring the inseam can be done relatively easily, requiring only 2 people and a book only taking a fraction of time. To begin:
Alternatively, if visiting a store and receiving a professional bike-fit this will be done for you. This is recommended if you do not feel comfortable measuring the inseam or your bike fit size yourself.
How Do You Figure Out Your Bike Size
Bike sizing can be a bit of a pain sometimes because there isn’t always one universal system of measurement thats the same for all types of bikes and all riders.
Depending on whether youre looking for an adult bike, a kids bike, a road bike, or a mountain bike, youll find that there are a few ways that manufacturers designate size. Keep reading to learn how bikes are sized.
Todays Designs Are Not Square
The only reason the top tube measurement was ever remotely relevant was due to the squareness of steel road frames.
They had a top tube and a seat tube that commonly measured the same and a simple beauty to the sizing process followed.
That sizing process culminated with riders standing over a frame and smacking themselves in the nethers with the frame to find an appropriate size. How elegant.
All this was largely an artifact of Italian designs and several archaic seat height methodologies, some based on the C.O.N.I. database of bike measurements that may or may not have fit professional riders . But I digress.
The reality is this: with modern carbon designs, the top tube has been a misleading measurement since the first signs of sloping tubes.
Ironically, if you asked a modern frame builder to create a new bike for you, theyd likely first ask for your stack and reach.
Fake news theres horizontal top tube, the crowd retorts.
What about offset seat tubes? How does a corrected top tube measurement take that in to account? Simple, it doesnt. Not to mention the variation of measuring that theoretical top tube.
Dont believe me? Pick five random brands and look at their geo drawings and it quickly becomes apparent how proprietary measurements have become.
There is nothing proprietary about frame stack and reach, except the actual measurement, of course. Furthermore, its unaffected by anything an industrial designer can influence.
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How Do I Choose The Right Bike Size
The most simple and effective way to get an idea of your bike size is simply measuring your height. Simply stand straight against a wall and let somebody mark the top of your head. Of all proposed methods this is the least accurate but it can already give you an idea of your bike size.
As mentioned before, for BMXs it is the only measurement you need.
Whilst measuring your height also measure your inseam which will determine your standover height. Inseam is the measurement from the floor to your crotch and is even considered a better value to determine bike size over height, although it doesnt hurt to have both measurements
You can measure your inseam pretty easily with a book and the help of your partner or a friend:
- Stand with your back against the wall with your feet shoulder width apart.
- Put a book between your legs as if it was a bike seat
- Let the second person measure from the floor to the top of the book
I advise to have at least 2 cm clearance between your top tube and your crotch on a road bike and 4 cm on a mountain bike. So you can hop off your bike quickly in case of emergency.
In case your height and inseam still putt you in-between two sizes then your upper body will select the best-sized bike for you. To determine if you have a long or short reach youll need to calculate your Ape Index. This is your armspan minus your height.
Calculate your bike size with a easy math
1 in = 2.54 cm
1 cm = 0.39 in
9.Online bike size calculator
Seek Advice On Your Road Bike Size
Above all, when selecting a new bike or if you have fit problems or discomfort, wed recommend asking for advice from an expert. That might not come free, but it should be worth the expense to up your riding enjoyment, avoid injury and ensure that youre getting the most from your cycling.
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Road Bike Sizing Calculator
The road bikes come with thinner tires as well as light frames. They are specially made for riding on paved and smooth surfaces that include roads, paths, and streets. A few of them might even handle gravel roads or dirt. There are so many different types of road bikes. The road bikes are generally used for commuting, racing, and touring.
Whilst styles differ, the main approach to road bike sizing does remain the same that is using the riders leg length and height to determine proper frame size. There is a road bike calculator that recommends the road bike frame size, depending on the measurements that you take. In case you do not know about your leg length, then you would get a large range of different frame sizes in order to try them out.
How To Adjust The Height Of A Quill Stem
Jack Luke / Immediate Media
Quill stems were the norm before A-head/threadless style stems hit the market. They are still commonly seen on bikes of all styles and disciplines.
Quill stems slide into the steerer tube of the fork and are secured with either an expanding bung or sliding wedge that presses against the inside of the tube.
Adjusting their height is slightly different but arguably much easier than a threadless stem.
Jack Luke / Immediate Media
Begin by loosening the bolt on the top of the stem. Most use a hex head bolt, but some will use an external bolt.
Jack Luke / Immediate Media
Once loosened, you may be able to freely move the stem.
If the stem hasnt been adjusted in some time, you may need to gently tap the bolt with a hammer to free the wedge or bung.
If the bolt is sitting proud of the stem, strike this directly. If it is flush with the top of the stem, you can use your hex key to gently tap the bolt.
Jack Luke / Immediate Media
The stem can now be adjusted to your hearts content. Be sure to check for any minimum and maximum insertion marks on the stem and adhere to these.
It is good practice to periodically grease the shaft of a quill stem because they frequently seize if left dry.
Jack Luke / Immediate Media
Once you have set the height of your stem and lined it up with your front wheel, you can re-tighten the wedge bolt to spec.
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Bike Size Chart: How To Find The Right Size Bike
As is the case with your helmet, riding shoes and riding apparel, you want to make sure that your bike is the right size for you. Not only will the right size bike offer the most comfortable ride, it will also let you get the best performance out of your bike. The last thing you want while riding is bumping your knees on the handlebars because your bike is undersized, or not being able to pedal smoothly because your bike is a bit too big.
Whether youre looking at various bikes in the store or searching online, sizing is a very quick and easy process.
What Is A Professional Bike Fit
A professional bike fit isn’t just for professional bike riders!
The best way to be sure that your bike will fit you and that its set up right is to invest in a professional bike fit. A bike fitter will spend several hours with you, setting you up on a test bike indoors and having you ride it as they adjust the position of your saddle, bars and other components, to see how these changes affect your riding.
A professional bike fit will prevent you buying the wrong sized bike
Here’s what to expect at a bike fit , but in summary, youll come away with a list of measurements that you can use to zero in on the best road bike and size to suit your needs. It should also be portable if you decide to swap bikes or buy another one in future.
Its worth bearing in mind that your optimal fit may change over time, as age, weight and flexibility change. So weve advise getting your bike fit recallobrated in our page dedicated to five reasons you need to get a fresh bike fit .
The process will be an additional costs on top of buying a bike, although some bike shops offer it discounted, or offer a basic one for free when buying a bike with them. In fact it’s one of the most important aspects of what to look for in your first road bike . It will save you a fortune on buying the wrong bike, and ensure that youve got the right dimensions to buy the right size bike for you.
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How To Position Your Bike Seat
Once you buy the perfect bike with the best frame size for you, its time to set the seat height. Getting the correct height is crucial to avoiding injury and getting the most out of the bike. There are many formulae and methods used by the professionals, like the 109 Method, Le Mond Method and Holmes Method, each with their pros and cons, but lets start with a basic trick to get a ballpark idea of what is safe. Get on the saddle of your bike and move one pedal to the lowest point with your feet planted flat on it. Check three things:
- Is your leg on the lowest pedal fully extended and straight, with the foot flat on the pedal?
- Does your knee stay below the horizontal line when the pedal is at the highest point?
- Can your toes touch the ground, when you are in the saddle, and the bike is upright?
If the answer to all these is in the affirmative, the saddle height is ideal for you. If not, try changing it until you get all three right. And in the even you cant meet these three criteria for any seat height on your bike, that means that you need to get a different frame size.
How To Flip The Stem On My Bike
Colin Levitch / Immediate
If spacers arent enough to achieve the effect you want, you can flip the stem to make a further change to the bar height.
Most mountain bikes will be set up with the stem in a positive position, creating an upward angle, but you can use it the other way round.
This uses all the steps above with the addition of unbolting the handlebar from the front of stem.
Oli Woodman/Immediate Media
With the bikes wheels firmly on the ground, make a mental note of the handlebar angle and the brake lever angle.
Matching up a piece of masking tape on the faceplate and bars will make sure you get the angle spot on when refitting.
Undo the bolts that hold the handlebar to the front of the stem. Remove the stems faceplate and store it somewhere safe.
Oli Woodman/Immediate Media
Let the handlebar gently droop to the side and now follow the procedure for swapping spacers, outlined in steps 1 to 4 above.
Oliver Woodman/Immediate Media
While the stem is off the bike, flip it over and then slide it back onto the steerer tube.
Reinstall the handlebar, replicating the previous brake lever and handlebar angle.
Tighten the faceplate to the manufacturers recommended torque . Ensure that all bolts are done up evenly, a little at a time, and that there is an even gap top to bottom with the face plate once theyre tight. If the gap isnt even, the handlebar is being pinched.
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Handlebars And Their Position
A bike that fits right has handlebars in the correct position. When positioned incorrectly, you can suffer from back pain, wrist soreness, and shoulder discomfort from the strain. With racers or touring bikes, you will find that the handlebars are the width of your shoulders. Road bikes have their handlebars positioned approximately an inch below the top of the saddle. A mountain bike has even lower handlebars to create a greater center of gravity. Hybrids have a high seat, so your body is positioned in a very upright fashion. All these positions are not written in stone. Most bikes allow you to adjust the handlebars. When sizing a bike, you must think about the handlebars and how it fits your body and riding style.
Bike Size Based On Your Height
This is the easiest method by which you can select the bike size. Its the fastest method to find a bike size. All it takes is to compare your height with the general bike sizing chart below.
Unfortunately, this method does not take into account the type of bike. This means it is not as accurate as the methods below. So, there is a risk that the bicycle wont fit you perfectly.
The right way to set the correct saddle height:
Now, in ideal, your leg should be able to spin the pedals so that there isnt too much of an angle , or if the heel doesnt touch the pedal on its lowest position
- When your hips are rocking when pedaling the saddle is too high.
- When your legs dont stretch at least 70% of the capacity the saddle is too low.
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Does Wheel Size Affect Sizing Is A Bike Wheel Size Chart Needed
On road bikes and hybrids, no, as these bikes will all have a similarly sized wheel. However, on a mountain bike, the answer is yes. Mountains bikes now come in three different wheel sizes. You can find them with 26 wheels, 27.5 wheels, or 29 wheels. If all three have a 15 frame, there will be a height difference between them due to their wheel size. Bike frames are measured from the middle of their bottom bracket to the end of their seat tube. Your wheel axle height sets your bottom bracket height.
If we take the 26 wheel as the base height, the axle height for a 27.5 wheel will be 0.75 higher. If we then look at the 29 wheel, its axle will be 1.5 higher. This is because the axle sits in the middle of your wheel. We then divide the difference in wheel height by half to get information on how much higher the axle sits.
A 15 frame will be 15.75 on a 27.5 or 16.5 on a 29. Some manufacturers have worked on the mathematics and geometry to keep the differences closer than this. Others have not.The good news is, we have the option of knowing stack and reach, and this will tell us how close the fit is for you. We have more on stack and reach below.
Mens Mountain Bike Size Chart
Ideally, mountain bikes are meant for rough off-road terrain. Mountain adult bikes have low gear and upright handlebars helping one to pedal up steep terrain. Mountain bikes come in different sizes based on the adult rider height and frame size.
It is advisable that the type of bike you select have shock absorbers. Most mountain bikes also have wider tires to help improve rider experience when rough riding. Hardtails are bikes with front shock absorbers only while Duallies have rear and front shock absorbers. However, a rigid bike has no shock absorbers. Also, ensure you pick the correct size to ensure an upright position when riding. We have a full mountain bike size chart here
Please find the mens mountain bike size chart below!
|Above 19 inches
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Effective Top Tube Length
The modern sloped top tube design, measured using effective top tube length, affects the reach of a bike.
A longer top tube means there is more space between where you sit and where you place your hands which determines upper body posture.
Too long of a top tube and you will feel stretched out while a short top tube makes for a cramped feel.
What Bike Size Do I Need
With this bike size calculator we’d like to give you an idea which sizes of bike frames you should look at. But first we need to start with a general disclaimer – you should treat this tool as a guideline only. There are many different bike brands and models, so frames and general structure may vary a lot between them. Also, every cyclist is built slightly differently, and may have particular needs and preferences.
The frame size is usually measured as the distance between the top of the seat tube and the center of the bottom bracket. Sometimes, the center or top of the top tube is chosen as the first point.
Our bike size calculator determines bike frame sizes on the basis of your inseam measurement. The formulas vary for different types of bike:
1. City/trekking bike frames
Trekking frame size = inseam x 0.64
2. Road bike frames
Road frame size = inseam x 0.67
This is the formula created in the ’80s by Cyrille Guimard, famous French coach and former pro cyclist.
3. Mountain bike frames
Mountain bike frames are smaller than road bike frames. Usually, a frame shorter than 4 – 5 in is a good start
Mountain frame size = Road frame size – 11
You probably noticed that the formulas don’t directly take your height into account. However, when you choose your height from the drop-down list, a probable range of your inseam will appear . This bike size calculator is suitable for both men and women.
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