How2 :: Fix a Flat

Now is the time for all cycling Ladies to learn how to change a flat.  Now, I am not saying that you have to change your own flat tire, there will always be someone around willing to do it for you, and why not allow them?  You don’t want to get dirt under your fingernails, or -gasp- break one showing your flat-changing prowess.  However, there may come a time when you need to rescue a fellow cycling lady, or even the random guy who doesn’t know how to easily pull replace the rear wheel after a flat change.  Trust me, you want this skill, even if you never have to use it.

Here are the simple steps for those of you who have tubes in your tires:

1. Before removing your rear wheel- be sure to shift into the smallest cog in the rear to ensure ease of wheel removal and replacement! Undo the quick release lever, the rear lever will likely not need to be unscrewed at all, only the front.   Disc Brakes: It is important you do not engage the brake lever on your disc brakes while the wheel is out of the frame. If you do, your brake pads will become stuck together.  In order to separate them and push the pistons back inside the brake, you can use a flat head screwdriver or similar tool.  Depress the pad, you may use some pressure, to get it back into the brake. The pad should be flush with the inside of the brake… not sticking out at all.

Before removing a rear wheel, be sure to shift to the hardest gear/smallest cog in the rear.

Before removing the wheel, shift into the highest gear/smallest cog to ensure ease of rear wheel removal and replacement! Very key!

If you have any remaining air in the tube, release it now!

If you have any remaining air in the tube, release it now!

2. Release any remaining air from your tube. If you have a Presta valve (skinny with threads and a little screw/press top) simply unscrew the end and depress the lose top to release the air. If you have a Schrader (a black rubber coated valve stem with threads at the top and a small valve sticking out), simply depress the valve inside the core to release the air.

As seen on mtbchick.com, Crank Brothers Speed Lever easy to use!

As seen on mtbchick.com, Crank Brothers Speed Lever easy to use!

3. Remove one side of the tire from the rim. The best tool for the job is the Crank Brothers Speed Lever, you may be able to do this with bare hands or any other tire lever. I prefer Pedro’s Levers or the SOMA steel core levers, which won’t break.  For the Speed Lever: Simply expand the lever, wedge the hook under the bead of the tire, connect the other end of the speed lever to your axle, and push with your thumb all the way round the tire until one side is fully disengaged from the rim.

Carefully remove the tube.

Carefully remove the tube.

4. Carefully remove the tube, making sure to note the position of the tube in the tire.  Reason why: you are going to check to see where the puncture is on the tube in relation to the rim and tire so you may find and remove the culprit of your flat tire.

Find the hole in the tube!

Find the hole in the tube!

5. Seek out the hole in the tube. Keeping the tube in line with the tire so when you find the puncture you can also find the culprit!  If you find to slits, not round holes, you have what is known as a “snakebite”. A snakebite happens when there is too little air in the tube, and the impact of the bicycle compresses the tire all the way to the rim, and the rim slices the tube on both sides.  This is non-patchable.  My theory on patches, and one I carried over from Cannondale’s Troy Laffey, is a tube with a patch is still a tube with a hole in it. Go for complete integrity and replace the tube, unless it is your last resort.  You can recycle tubes to Pedro’s or to Totally Tubular, two companies who use tires and tubes in their products.

6. Once you find the hole, locate the culrpit on the tire or in the rim. CARE fully run your fingers inside the tire and alone the rim to check for anything that may cause a flat tire.  Could be a piece of glass, shrapnel from a retread explosion, goathead or other thorn, or a burr on the rim, or even rim tape that has shifted exposing the nipple holes.  Carefully check so you don’t run the risk of reflatting before you even swing a leg back over the bike!

7. After removing any and all flat producing items, proceed to install the new tube. Fill the tube with a very small amount of air, enough to give the tube some shape, but not to fill it out too much. Too much air and you won’t be able to get the tire back on. Not enough and you endanger yourself of a pinched tube, which will cause an explosion not unlike a car backfiring and will send you and anyone in your vicinity straight up into the air, and not transcendentally.

8. Replace the bead of the tire in the rim. Using you Crank Brothers Speed Lever: snap onto axle, and press the downward facing hook onto the rim, place the bead of the tire into the rim, and press following the bead all the way around.

9. Reseat the Bead. !!IMPORTANT!! Explosion Prevention! If you or someone you know has ever exploded a tube while pumping after a flat tire change, you know what I am talking about. Sometimes experience is the best teacher, however, I assure you this is not an experience worth having.  Holding the tire with both hands, squeeze all the way around the entire tire, pulling the bead back to ensure the tube is not pinched in between the bead of the tire and the rim. The tube should be fully inside the tire, and you should not be able to see it.  Flip the wheel so you can now check the other side of the tire.  Not only are you checking for the tube stuck in between the rim and the tire bead, you are seating the tire so that you prevent tread wobbles from a not so straightly installed tire.

10. Air it up! Be sure if you are trailside or roadside to pump enough air to get you home without a pinch flat. The sidewall of your tire will give a range of air pressure, eg, 40 psi-80 psi.  For most women, the lower range of the pressure will give a comfortable and safe ride. Too much air pressure and you will have no traction on the downhills- not enough and you are in danger of pinch flats or snakebites!!

11. Reinstall the wheel onto the bike.  All quick releases should be properly tightened and secure.  Rule of thumb is that pressing the lever to closed leaves a small impression on your hand, but is not so hard you pop veins straining to get it closed. Standing on your lever is a terrible idea.  Again, I recommend Crank Brothers split lever skewers.

** For Disc Brakes: It is of utmost importance to have your rear derailleur in the smallest cog when replacing your rear wheel, it will allot you to easily line up your rotor with your brake pads.
repair_flat5

Pinched tube=badThis is a pinched tube=bad

This is a pinched tube=bad

Replace the bead

Replace the bead

repair_flat8

Checking for a pinched tube, seating the bead.

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