Fixing Flat Tires

How to Change a Tube

This manual teaches you how to change a flat tire, If the damage to your tube is minor, you may be able to patch the tube instead. We always recommend patching the tube when your tire goes flat, but if the hole in your tube is too big to patch, you will need to replace the tube instead. If your tube is patchable, please look for our "How to Patch a Tube" article located in the Troubleshooting section of our Help Center.

• Removing the Wheel
• Removing the Tire
• Check for tire damage
• Reattach the tire
• Insert new tube into tire
• Attach the tire to rim
• Reattach the wheel

• Inflate your tube

Removing the wheel from the bike

Firstly, remove the wheel with the flat tire from your bicycle. If your wheel is attached with a quick-release you can simply unfold the quick-release lever, loosen the acorn nut on the opposite side and pull the wheel down and out of the fork's dropouts.  If the flat tire is on your rear-wheel, or if the wheel is not on a quick-release, you will need to use an adjustable wrench or a socket wrench to loosen the nuts on the sides of the wheels axle, and then pull the wheel down and out of the dropouts.

Take extra care during this last step if you are removing the rear-wheel, as you will need to move the chain off of the gears as you pull the tire out of the dropouts. If you are removing the front wheel, make sure to place the fork down gently so that you do not damage the fork's dropouts.

Removing the tire

Begin by inserting one of your tire levers between the wheel's rim and the edge of the tire. Insert a second tire lever a few inches from the first one, and work the spoons around the tire until the entire edge of the tire has been freed from the wheel's rim. Most tire levers come with a notch on the rear which can lock it to the spoke. Leave the opposite side of the tire attached to the rim. 

Starting at the side opposite the valve stem, pull the damaged tube out from inside the tire, and remove completely. You will need to remove the cap from the tube's stem before you can remove it from the tire's rim.

Check the tire for damage

Inspect the inside of your tire to ensure that there is nothing stuck inside the rubber. Nails, thorns, and construction staples are a common cause for flats, and if you do not find and remove the cause of your flat, it will likely puncture the new tube. You may find it easier to find the source of damage by using a bright light. Inflating the removed tube is another easy way to find the location of the puncture. If it is still hard to find, inflate the tube and apply soapy water. The leak will cause the liquid to bubble. 

Depending on how bad the damage is, you may need to replace the tire as well. Be sure to check for wear on your tire's treads, sidewalls, inside edge, and wire bead. If the tire looks worn, utilize this opportunity to replace it. If the tire has a puncture larger than 0.5cm, it should be replaced. 

Insert the new tube

Before you can insert the new tube into the tire, you will need to slightly inflate the new tube. This will help prevent pinch flats. Begin by threading the valve stem through the hole in the rim, ensuring that it is in straight. If the valve stem is at an angle, there is a high likelihood that it will be damaged and leak air. 

Once the valve has been properly seated, work the tube into the tire. Make sure there are no folds or twists in the tube, for this will cause a pinch flat. 

Reattach the tire

Starting at the valve stem side, squeeze the edge of the tire underneath the lip of the rim. Continue this around the wheel. If your tire has a wire beam, it might become too taught to fold under. This can be remedied by using a tire lever or two. 

Reattach the Wheel

Now that the new tube and the tire are properly seated on the wheel, you can reattach it to the bike's dropouts. Being mindful of your disc brake rotors, take the loosened quick-release or axel, set the wheel into the dropouts, making sure the full weight of the bike is on the ground. This will make sure the wheel's axle is fully seated in the dropouts and your wheel is straight (true). Tighten the wheel using the acorn nut and secure it by closing the quick-release lever or tightening the axel nuts. 

You can check your work by giving the wheel a spin. If the wheel wobbles or makes a scraping noise, you will need to go back a step and ensure that the wheel is fully seated and properly aligned. Once the wheel is in proper alignment, make sure to lock it tight.

Inflate your tube

Now that the wheel has been reattached to your bicycle, inflate the tire to the recommended PSI, which can be found on the sidewall of your tire. All tires have a range of acceptable tire pressures. If you plan on using your bike off-road, inflate the tire to a level on the lower end of the acceptable range.

A lower PSI will provide more shock absorption and better grip on the road, but it will also cause more friction, which will lower your top speed and place more strain on your bicycle's motor. A higher PSI will reduce the amount of drag, but at the cost of less shock absorption. We recommend testing your bike at different tire pressures until you find what level is good for your riding style.

Depending on which type of valve stem your rim accepts, you will have a Schrader valve or a Presta valve. Schrader valves can simply attach to the end of your pump. Presta valves need to have the end cap unscrewed at the tip of the valve before you start pumping. Be sure to tighten the cap once finished.

Make sure that you are using the correct pump for your valve. Some pumps will have two ends, and others should come with an adapter. If your pump has two ends, the end with the smaller hole is for Presta valves.

Be sure to inflate your tire slowly, so that the tube seats properly inside of the tire. If you inflate the tire too quickly, the tube may get pinched and pop. If you notice that the part of the tire is unseating from the rim, stop pumping the tire and press in the pin on the tube's stem valve to deflate it. Once the tire has been deflated, reseat the tire's edges into the rim, and then slowly re-inflate it.

When you have inflated your tire, replace the plastic cap at the end of the tube's stem. If your tube has a Presta valve, make sure to spin the metal end cap at the top of the valve until it is closed tight before you replace the plastic cap.