If you’re looking to buy a new bike or upgrade your old one, you’ll need to know how to measure bike wheel size. It’s not as complicated as it sounds, and with a few simple tools, you can do it at home. Here’s a step-by-step guide to help you get started.
- 1 How to Measure a Tire on a Bike or Bicycle
- 2 How To Measure With The Standard Method
- 3 How To Measure With The ISO Method
- 4 How To Measure A Bike Wheel (Rim) For Tire Size
- 5 How to Measure Kid’s Bike Wheels
- 6 The Most Popular Bike Wheel Sizes
- 7 Maintenance of your Bike Wheels
- 8 Bonus Tip: Calculate The Circumference Of The Bike’s Wheel
- 9 FAQs
- 10 Conclusion
How to Measure a Tire on a Bike or Bicycle
There are a variety of approaches depending on how long you have to spend measuring your bike’s wheel.
First, it is possible to contact the bike manufacturer or the shop that sold it. Manufacturers and retailers keep track of all measurements and sizing information.
Be aware that retailers can be challenging to reach and often take a while to respond. You can usually find the required information on the tire wall (side) if you have a bicycle tire on your wheel – see the image below.
The European Tire and Rim Technical Organization (ETRO) determines the tire wall’s size. This will usually look something like this.
Don’t worry if you can’t find the size on your bike tire. There are several ways to measure your bike’s wheel, which will help you determine the correct tire for your bike. These steps can be helpful in cases where you don’t have a bicycle tire or custom wheels. There are usually two main ways to measure the size of a bicycle wheel: the Standard Method and the Custom Method.
The Standard Method (Easiest and Fastest Ways to Find Bike Tire Size)
To keep the bike upright, lean it against a wall or use the kickstand. You can measure the wheel without falling over if the bicycle is upright. A retractable metal tape measure is more durable than plastic tape while still allowing you to use your other hand if you’re measuring the bike yourself.
Measure the Inches distance between the ground beneath the tire and the wheel’s center point. This dimension is the wheel’s radius, which is equal to half of its diameter. Multiplying the length by two will yield the tire’s diameter. Except for BMX bikes and mountain bikes, most adult bicycles have wheels between 26 and 29 inches in diameter.
Measure the tire’s flat area across the tread from one side to the other. The tire’s width determines the distance. Depending on the tire’s intended use, there are several variations. Broader treads are required for more rugged terrain, while narrower tracks ensure a smoother, faster ride.
The diameter should go first, then the breadth. Keep in mind that traditional or standard sizes place the diameter first and then the breadth when purchasing new tires.
The ISO Method (Most Accurate Way To Measure Bike Tire Sizes)
Verify whether the wheels on your bike are measured according to the ISO standard. The International Organization for Standardization (ISO) measures the diameter of the wheel on your bicycle in millimeters. ISO sizing is the most accurate technique for measuring tires at home. It would help if you got the most accurate measurement possible from it.
Most tires are measured using the ISO and standard techniques. In order to allow for easy inspection, their sizes should also be printed on the tire’s sidewall. Ensure the bicycle is propped up on its kickstand or against a wall. Only measure in millimeters from the center of the wheel to the inner edge of the tire. Multiply the number by two to get the diameter.
The ISO standard includes both the tire width in millimeters and the bead seat diameter (BSD). Measure the tire’s width in millimeters. Go from one side to the other while following the same steps as before. Keep in mind that different tire widths can be used on the same bicycle wheel as long as the difference isn’t too large.
How To Measure With The Standard Method
Let’s begin with a step-by-step guide to completing the method for measuring bike wheels:
- Start by placing your bicycle against a wall or on a kickstand to ensure stability.
- Use a tape measure to place the tape’s bottom at the tire’s lowest point (on the ground). Then measure straight down to the center of your bike wheel to determine the radius of your wheel (as shown in this image).
- To find the wheel’s diameter, multiply your wheel’s radius by two.
- Measure the tire’s width by placing the measuring tape on the top.
- These numbers are your standard measurements. Make sure you list the tire diameter first.
- Bike wheel diameters will be rounded to within a half-inch. If your measurements are slightly larger or smaller, you can round up or down to get the closest size.
How To Measure With The ISO Method
This guide will show you how to measure your bike tires using the ISO standardization method.
- Some wheel manufacturers and brands don’t use ISO standardization. If you have a tire on your wheel, make sure to check for a printed ISO measurement.
- Check the wheel rim if there is no ISO measurement visible on your tire.
- If you cannot find the measurement you need, place your bike against a wall or use its kickstand to ensure it is stable.
- Start at the center of the wheel with a measuring tape and measure to the tire’s inner edge.
- You don’t need a tape measure that measures in millimeters. Instead, measure in inches, multiply it by 25.4 (e.g. 12.25″ x 25.4 = 311mm).
- This length should be taken into account and multiplied by 2 to get the diameter of your wheel (311×2 = 622mm).
- You can measure the tire’s width from one side to the other.
- Now you have all the necessary calculations for the ISO method. This measurement is first listed with the tire’s diameter (25-622)
How To Measure A Bike Wheel (Rim) For Tire Size
You can also measure the rim width of your bike in millimeters if you don’t have the tire on your bike.
The following charts, which are based on the most common tire-wheel combination currently available on the market, illustrate the concording tire size and rim length.
While many rims will display their size, some may not.
If you can’t find it. Measurements on the rim of your wheel will determine the correct tire size. Follow the steps below to find out.
- Place the bike vertically so that there is no tire on it.
- Use a measuring tape to press against the rim where the tire bead is usually placed.
- As shown in the above image, measure a distance between the rim and the interior (as shown).
- This width can be used to create the table below.
These charts are based on average measurements. It is important to remember that you should double-check your tire manufacturer or retailer to ensure all sizes are compatible.
You should also consider the tire clearance for your rear triangle and fork. You can damage your frame by choosing a tire too large. A tire too small can cause damage to your inner tube and rim.
Road Bike Tire Size Chart
Mountain Bike Tire Size Chart
How to Measure Kid’s Bike Wheels
The child’s inside leg is measured by the distance between the top of the crotch and the ground.
The inseam measurement establishes the minimum height required for riders to sit on the bike seat and have their feet touch the ground.
The simple instructions below will walk you through the process of taking a child’s inseam measurement for a bike.
- The youngster should stand with their feet shoulder-width apart, back to a wall, and their shoes on.
- The spine of a robust book should be pressed firmly against the wall, and the book should be placed as high between their legs as is comfortable.
- Ask the child to move away from the wall while maintaining firm control of the book.
- Calculate the distance from the book’s top to the ground using a measuring tape.
- This length is your inseam. To avoid having to remeasure, make a note of it.
The Most Popular Bike Wheel Sizes
Every mountain bike and road bike has a different set average wheel size. Each size has its own set of drawbacks and benefits.
What Is The Standard Size Of A Road Bike Wheel?
700c is the most popular size of a road bike wheel. This site has been used for many years.
700 is the diameter of a wheel at 700 mm. The “c” refers to an old French width code for tires.
With “a” being the narrowest width and “d” the largest, “c” being the larger size.
The Most Common Size of Mountain Bike Wheel
Mountain bike wheels are available in three sizes: 26-inch/559 wheels, 27.5-inch/650b wheels, and 29-inch/622 wheels.
The 26-inch size of mountain bike wheels was once standard and is lighter and more agile than the larger wheels.
Despite being popular in the past 26-inch wheels are not the norm. Larger wheels offer better grip, traction, and durability, which has made them more popular.
The 27.5-inch and 29-inch wheels provide a more comfortable ride without compromising some of the acceleration potentials of a 26-inch.
Maintenance of your Bike Wheels
Examine the Rims and Hubs
If you use rim brakes, your rim will last for more than 20,000 miles. If you are using disc wheels, it will last forever. You should inspect your wheels more frequently if you use rim brakes. Your bike wheels will wear quicker in wet or muddy conditions.
Most rims have a line running along the braking surface. If your rim is worn out, it will disappear with time. The bow can split under tire pressure if the sidewalls of your rim are too thin.
You should also inspect the hubs to ensure they are in good condition. You can replace the entire wheel if your seat is in good condition.
After some time, tighten your spokes a bit
Loose spokes could be another reason your wheels don’t work. With your fingers, squeeze two spokes toward each other. You will be able to tell if the spokes are loose or tight.
You can tighten them by using your fingers to determine which part of the wheel is closer to the frame. Use a spoke wrench to tighten the spokes evenly and slightly. After tightening just a few spokes, the wheel will be stable. If it still doesn’t, you can move on to the next step.
True the Wheels
The final solution to your actual problems is the work-stand. Make sure your wheels are always accurate. If they aren’t, fix it. You’ll notice that things aren’t working as they should, depending on the type of bike brake you have.
You can’t ignore it, and your wheel will begin to wobble. If you have rim brakes, you may experience brake rub. Your wheel will eventually become weaker and more worn. If you want a perfect bicycle, you might have to replace your wheel sooner than expected.
Bonus Tip: Calculate The Circumference Of The Bike’s Wheel
Take the circumference into consideration. In order to properly calibrate a bicycle speedometer, odometer, GPS, or computer, you need to know how far around the outside of the wheel it is. Similar to how changing the size of your car’s wheels would cause the speedometer and odometer to give inaccurate readings, bicycle equipment must be set up based on the size of your tires. If you’ve recently purchased a cyclometer or need to calibrate an existing one because you’ve switched to tires with a different thread size, you’ll need to figure out the diameter of the wheel.
The tire’s diameter equals 3.14 pi, which is multiplied to obtain the circumference. You can quickly determine the circumference of any circle if you already know the tire’s diameter from side to side.
You can use one of the many online calculators to determine the tire’s circumference if you already know its diameter and breadth.
Measure the circumference with a string. By evenly wrapping a rope around the outside edge of the tire, you can still determine the wheel’s circumference, even if you don’t know its diameter. Mark or cut the thread so it can be traced back to its starting point, then measure the length to calculate the circumference.
Put a spot of wet paint on a bicycle tire’s tread. Make sure the color touches the ground twice by pushing the bike in a straight line for at least two rotations. Measure the distance on the ground between each paint spot to get an idea of the tire’s circumference.
How do you take off a bicycle wheel?
Depending on which side you want to go to, you can remove a bike wheel from either the front or back.
You can remove the front wheel by releasing your brake and flipping it over. Next, open the quick-release or unscrew the wheel nuts and pull it off the fork.
You can remove the back wheel by moving the chain onto the smallest cog and opening the break. Next, you will need to loosen your quick-release or wheel nuts. The rear derailleur must be pulled back and the wheel removed.
How to measure bike wheel size for the inner tube?
To measure the wheel size for the inner tube, you will need a measuring tape and a way to mark the circumference of the wheel. Place the measuring at the center of the wheel and measure the distance around the outside edge of the tire. Make a mark on the ground at the point where the tape meets the starting point. Repeat this process for the other wheel. The distance between the two marks is the circumference of your bike’s wheels.
Is it possible to put a road bike wheel on a mountain bike?
It is possible to put road bike wheels on a mountain bicycle frame. This is a popular choice for commuters who bike to work and then switch to MTB bikes to ride the trails.
Remember that mountain and road bike wheels are very different, so you may need to adjust other parts of your bike.
It is possible to put road bike wheels on a mountain bike!
Is it possible to put a mountain bike on a road bicycle?
For better aerodynamics, a road bike’s frame is usually narrower and has less clearance than a mountain bicycle. It has a lower wheel clearance, so the larger tires and wheels that come with a mountain bike will not fit well.
However, it is possible to fit 29-inch mountain bikes with narrow ties on 700c road bikes. But, too large wheels can cause damage to your bike. Do not risk it if you are unsure.
The great thing about this little article is that BSXInsight will give you some of the simplest methods to measure bike wheel size. Hopefully, you can use them to get started on measuring your bike wheel size. What do you think? Comment below!