• Come to a controlled stop on the right of the road away from traffic.
  
  
• Change your flat away from the road. Be certain you are clear of traffic.
  
  
• Find a spot that is clean, free of mud and allows you to not lose parts if they are dropped.

TIP	On a group ride let others know you flatted by raising your arm. Right arm to signify a rear flat, left arm to signal a front flat.

• Stand behind the rear wheel. Open the brake quick release lever by rotating upward.

  This will enable you to remove the wheel by opening the brake pads allowing the tire to pass through without getting caught on the brake pads.

• Make it easier to remove your rear wheel by shifting to your hardest gear- that is the smallest cog on the gears in the back of your bike.

  This cog is located at the most outboard (farthest right) position from the center of the bike.

• Once you've shifted down to your smallest size cog located at the outermost position of your gears then pick up your rear wheel and use your other hand to pedal the bike.

• When you pedal the bike it will shift to the smallest cog, sliding the chain downward and outward away from the center of the bike.This will also make re-installing the wheel easier when you are finished.

• Open your rear wheel quick release lever. Use your entire hand for leverage.

  Brace the heel of your hand against the center of the quick release skewer. Wrap four fingers around the lever. If your lever is positioned correctly you can pull the lever open.

  If your quick release lever is aligned with your chain stay it will be impossible to get your hand behind the quick release lever. Remove your helmet and loop part of your chin strap around the lever- then pull the lever open using the chin strap!

  The best place to position yourself is to kneel on one knee behind your bike, supporting your bike with your shoulder and two hands on the rear wheel quick release skewer and rear derailleur.

• While you are opening your rear quick release with your left hand, use your right hand to rotate the rear derailleur downward and rearward- toward you. This will open up the loop of chain allowing the rear wheel and cogset to pass out of the frame.

  Top view: Rider's perspective. Kneel on one knee behind the bike and open your quick release lever with your left hand as shown.

• Use your right hand to rotate the rear derailleur back and out of the way. This will allow you to easily remove the rear wheel without getting your hands dirty.
  
  If you rotate the derailleur correctly back toward you your hands stay clean! No need to touch the chain!

• With the rear derailleur pulled fully to the rear the wheel often simply falls out of the frame once the quick release skewer is opened.

  Some wheels need to be nudged forward and downward to come out. You can gently strike the top of the wheel with your free (left) hand to knock the wheel clear of the dropouts.

• Now you've got your quick release fully opened, derailleur and chain pulled back out of the way while keeping your hands clean and you tapped the top of your rear wheel with your left hand to knock it downward and free from the bike frame.

  The wheel often simply falls out of the rear triangle of your bike.

• Using your left hand to hold the left seat stay of your bike frame just below your rear brake, your right hand can grab the rim and guide the rear wheel out of your frame and away from the chain.
  
  It is necessary to angle the wheel to your left to get your gears out of the loop of chain.

• Now simply pull back and out- your rear wheel is off and your hands are clean!

  Here's another angle on the proper posture, technique and hand placement for removing the rear wheel and holding the bike.

  This technique enables you to easily control the bike and prevent it from falling over while simultaneously removing the rear wheel.

  Lay your bike on the left side to prevent leaves and dirt from getting on your chain. Be sure to lay your bike down away of pedestrians, other cyclists and cars.

• Everything you need to change a flat can be carried in a compact bag under your saddle.
  
  
• Remove your bag and set out the tools and spares you need to change your flat.
  
  Here we see the spare inner tube, an extra CO2 cartridge, the CO2 filler device and the head for the filler as well as a self-adhesive patch kit and compact multi-tool allen wrench set

• Let any remaining air out of the tire. This will make removing the tire from the wheel easier.
  
  
• Remove your plastic valve cap if you have one.
  
  
• Open your Presta valve by unthreading the knurled brass cap. Never remove the brass cap.
  
  
• Once the cap is in the open position press the cap inward to allow remaining air to escape.
  
  
• Some Presta Valves have a threaded washer on them to prevent it from moving.
  
  If you have this washer you'll need to remove it before you can take your inner tube out.
  
  
• Unthread the washer and remove it completely.
  
  Be sure to set it somewhere so you can find it again.
  

• Begin removing the tire from the opposite side as the valve stem.
  
  Use your entire hand wrapped around the tire to work the tire off the rim. Older tires will come off easier than newer ones since they have stretched.

• Some tires are a very tight fit. If you cannot roll the tire of the rim with your hands then use one or two tire levers to help pry the tire bead away from the rim.

  Plastic tires levers will not scratch your rims and slide easier against the rim and the tire.

• Beginning at the opposite side of the wheel as the valve stem remove the flat inner tube from the tire.

• Finish removing the inner tube by pulling the valve stem up and out of the rim.

• IMPORTANT: Carefully slide your fingers completely around the inside of your tire to check for foreign objects that may have created a puncture; glass, wire, thorns, etc. Remove any foreign objects to prevent additional flats.

• Remove the threaded washer to enable the valve stem to pass through the hole in the rim.

• Put a puff of air into the new inner tube to help the tube maintain its shape and make it easier to install. This also helps prevent pinching.

• Slide the valve stem downward through the hole in your rim. Be sure your fabric rim strip inside the rim is in the correct position and not damaged.

• Carefully tuck your inner tube up into the tire and pull the tire over the top of the tube beginning the tire installation.

  Now your primary goal is to get the tube into the tire without pinching it. Work carefully around the tire.

• Use your finger tips to tuck the inner tube all the way into the tire.

  The farther the inner tube is tucked into the tire the less likely it will be to pinch.

• Begin to roll the tire bead back onto the rim. Use your entire hand to gently roll the tire back onto the tire bead.

  This is often the trickiest step of changing a flat: Your primary goal is to get the new inner tube into the tire without pinching it.

• Thread the washer back onto your presta valve stem. Thread it up to the rim and snug it, but don't over tighten.

• Prepare your CO2 inflator by threading the inflation head onto the CO2 cartridge. This will pierce the top of the cartridge allowing the pressurized gas to flow into your tire.
  
  In the first photo above we show carrying the CO2 cartridge backwards to prevent accidental piercing of the cartridge. Simply turn the cartridge around when you are ready to prepare for use.
  
  BE CAREFUL: Never point the CO2 inflator or tip of canister toward your face.

• Double check that your presta valve is unthreaded and in the open position.
  
  
• Slide your CO2 inflator nozzle onto the valve and seat it firmly. Press upward with the CO2 inflator and downward on the tire, applying force agaist each other so they remain snug.
  
  
• Use the trigger unit on the CO2 dispenser to shoot short bursts of CO2 into your tire.
  
  
• Once the tire has begun to take air continue to fill it with short bursts from the CO2 inflator until at full pressure.

• Firmly pull the CO2 inflator straight downward and off the Presta valve stem.
  
  The CO2 will freeze moisture in the air and may momentarily freeze the inflator to the valve stem. Don't twist or wiggle the inflator on the valve: You could damage the valve.
  
  Be careful touching the valve stem or inflator nozzle- you could flash freeze your finger tips to it.
  
  
• Once removed from the valve stem point the CO2 inflator away from you and pull the trigger to expel the remaining CO2 from the cartridge.

• Replace your rear wheel into the bike frame by standing behind the bike and holding it with your left hand on the chainstay just beneath the brake.

• Use your right hand to sweep the wheel into the frame.

• Be sure to locate the cogset inside the loop of chain on the bike.

• Rotating the derailleur out of the way and setting the chain back on the outside (smallest) cog will make it easier to pull the wheel into place.

• You've check to confirm your wheel is centered in the frame.
  
  
• Now close your quick release lever firmly with the lever being located above the chain stay and below the seat stay of the frame.

• A good view from the rider's perspective of closing the quick release lever.
  
  This also shows the correct positon of the lever once it is closed.

• Use your shift lever to shift up to an easier gear.
  
  Pick up the rear of the bike and pedal to shift the chain up the cogset to an easier gear.

• Pick up your tools and flat inner tube.
  
  
• Re-Pack your bag and strap it back under you saddle. Be sure your straps are secure.
  
  
• Re-check the area for trash. Don't leave anything behind!