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700x38c Tire Size in Inches (In-depth Answer)

Bike tires come in a wide variety of sizes. 700x38c are common sizes used on road bikes, hybrid bikes, and wheelies.

But what does 700x38c mean and how do I convert these measurements to inches? I have all the answers you need in this article…

What Does 700x38c Mean?

700x38c is a bicycle tire size measured using the French system. This tire size is usually found on road bikes and hybrids.

The “700” part of the size represents the tire’s diameter. The “38” part means represents the tire’s width. The suffix “c” doesn’t mean anything anymore. It was historically used to indicate the tire’s bead seat diameter (edge of the tire that makes contact with the rim).

So, What Is 700x38c Tire Size in Inches?

Since 700mm is equal to approximately 27½ inches, one would expect a 700x38c tire to be the same as the 27.5-inch (27 five) tire but that is not the case. A 700x38c (also referred to as a 700cc) is used to refer to a 28” tire. A 700x38c tire can therefore be represented in inches as 28 x 1 ½ or 28 x 1 5/8 x 1 ½.

A 700x38c has ETRTO sizes of 38-622 and 38-635 which means a 38mm width and an inner diameter of 622mm and 635mm for 28” tires. The ETRTO (European Tyre and Rim Technical Organisation) exists to harmonize rim sizes and their associated tire sizes in the EU.

NB: 29” are also referred to as the 700c tires. They have the same inner diameter (622) as some of the 28” tires but they are much wider than the 28” tires. For this reason, they are not interchangeable. Examples of 29” tires are 50-622, 54-622, 55-622, etc.

Examples of 700x38c tires you can buy

Where Do I Find My Bike’s Tire Size?

Finding your bike’s tire size can be tricky, but it’s important to make sure you have the right information before you go out and buy a new set of tires.

Here are a few tips to help you locate your bike’s specific tire size:

  • Check your bike’s owner’s manual. This is probably the best place to start, as the manufacturer will likely list the exact tire size that is recommended for your bike model.
  • Check the sidewalls of your tires. Check the sidewalls until you see 700x38c and you have found your bike’s tire size.
  • Search online. If you don’t have an owner’s manual, or if you just want more information about different tire sizes, do a quick online search. There are plenty of resources available that will show you how to measure your current tires and find compatible replacements.
  • Visit a local bicycle shop. If all else fails, take your bike to a local bicycle shop, and ask one of their experts for help finding the right tire size for you

What Size Bicycle Tire Do I Need?

If your bike came with 700x38c tires and you want to replace them with new ones, specifically go for 700x38c tires. Don’t go for tires that are close enough in size.

Tire measurements that are close enough to your required tire size may not fit correctly. Never go for a close enough tire – go for an exact tire measurement.

And also always remember Brown’s Law of Tire Sizing: “If two tires are marked with sizes that are mathematically equal, but one is expressed as a decimal and the other as a fraction, these two tires will not be interchangeable.

What Inner Tube Sizes Should I Buy for a 700x38c Tire?

When buying inner tubes for your 700x38c tires, go for tubes that are specifically made for a 700x38c tire. So far, we know that a 700x38c can be a 28” or 29” tire. So, find out if your tires are 28” or 29”. This should be printed on the tires.

Since tube sizes will depend on how much they are inflated, the tube sizes will be shown as a range. For instance, you will find a tube labeled 700×35-43 (a 700×35-43 means that the tube can be used with tire sizes ranging from 700x35c to 700x43c).

To change your bike’s tire and tube, follow the steps in the video below:

FAQs

Is 700c the same as a 28-inch tire?

The problem with inch sizes is that they are not precise and lack accuracy. For instance, tires with internal diameters of 622 mm and 635 mm are both classified as 28-inch tires.

With this lack of precision and inaccuracies, it is correct to say that a 700c (with an inner diameter of 622 mm) is the same as a 28” tire.

To be on the safe side when it comes to sizes, buy the exact size printed on the tires you are replacing. If it is a 700x38c tire, go for a 700x38c tire.

Is a 27.5-inch wheel the same as 700c?

Since 700mm translates to approximately 27.5 inches, one would expect that a 27.5” tire is the same as a 700c tire but no, they are not the same. A 27.5” tire (also referred to as the 27 five) has an internal diameter of 584mm while the 700c has an internal diameter of 622mm. This means that the 27.5” wheel is smaller in size than the 700c wheel.

How wide are 38c bike tires?

A 38c bike tire is 38mm of 1.5 inches wide. This width is what you see when you stand in front of or behind the bike.

Why should you choose a 700x38c bike tire?

First, it provides great traction on both paved and unpaved surfaces. Additionally, it has low rolling resistance which makes it ideal for long-distance riding. And finally, its relatively narrow width makes it ideal for riders who want to avoid excess drag when cycling in windy conditions.

What is the recommended pressure for a 700x38c tire?

The recommended pressure for 700x38c is 85psi (pounds per square inch). Exceeding this may result in tire bursts wheel going way below the recommended pressure will lead to more friction making it harder to get the bike going.

What is the ISO tire measurement?

The ISO tire measurement uses a 5-digit number in the form of xx – xxx. The first two numbers (xx) represent the tire’s width while the last three numbers (xxx) represent the tire’s inner diameter. A 700x38c tire has an ISO measurement of 38-622 where the “38” represents the tire’s 38mm diameter and the “622” represents the tire’s 622mm inner diameter.
700x38c Tire Size in Inches