Change a flat
Change your flat in a flash with this step-by-step guide from Trek
Want to print this guide out and take it along with you?
Click here to download the pdf version.
1. Keeping the bike right side up, shift the bike into the smallest cog.
2. Open up the brake to allow the tire to pass through freely.
3. Standing on the non-chain side of the bike, flip the quick- release lever to the “open” position.
4. With your left hand, grasp the top tube of the bike and lift the rear wheel off the ground. Since the quick release is open, the wheel will fall out of the dropout.
5. While still holding the frame with your left hand, reach your right hand down to the small tab found on the derailleur above the small wheel. This will cause the chain to slack.
6. Move the frame away from your body so the chain falls off the rear wheel. Grab the wheel with your right hand and set the bike down on the non-chain side.
7. Aligned with a spoke, insert the scoop end of your first tire lever under the bead of the tire. Attach the hook of the tire lever to the aligned spoke.
8. Approximately 3 inches from the first tire lever, insert the scoop of the second tire lever and pry one side of the tire off the rim.
If the tire is old, you can probably get it off with your thumbs. If it’s a new tire, you’ll probably need tire levers to pry it off.
9. Remove the tube, and inflate it to see what type of puncture you have. Remove any debris lodged in the tire, so when you put a new tube in, it won’t flat right away.
10. Take your new tube and blow a small amount of air in it to give it shape.
11. Insert valve stem into the hole in the rim and feed the tube back into the tire.
12. Make sure one side of the tire is mounted all the way aroud the rim. For the second side, start at the valve hole and push the tire on with both hands, traveling in opposite directions around the rim.
13. Inflate the tube to give the tire shape. Inspect to make sure tube isn’t sticking out. Inflate to pressure recommended on the side of the tire.
14. Put the wheel back through the dropouts with the quick-release lever on the side opposite the chain.
15. Line up the chain and lay it on the smallest cog of the cassette. Click the dropout into the quick release part of the wheel.
16. Hold the quick-release lever in the open position while tightening the nut on the right side of the bike. Closing the lever should be hard enough to leave an impression on your hand.
17. Finally, close the brake quick-release to engage the brake pads closer to the rim.
Tire PSI: Mountain & Road Tires
The psi rating range on the side label of mountain bike tires is just that—a range.
The psi rating range on the side label of mountain bike tires is just that—a range.
Most riders over-inflate their tires for off-road mountain bikes out of fear of getting a pinch flat. For most riders a psi setting of 35-40 is fine. However, going too low in psi can lead to side wall cuts much like a tube pinch. So play with psi pressures to find the optimum level that will give you the best traction, control, and protection for the trail you ride on most.
Road bike tires can also be over-inflated. Tires are a form of suspension, and while over-inflated tires may benefit you with fewer pinch flats, they will slightly reduce your traction, and therefore speed. For example, instead of 120psi, try 100-110. You will gain traction and allow the tire to roll over small imperfections, giving you a smoother ride that is just as fast, if not faster, over the long haul.
Category: Cycling
