Zach Levenburg of 1977 Mopeds in San Francisco shows us how to fix a flat on the rear wheel of a moped.
* First, remove the rear brake cable with a wrench, and loosen the axle nuts using one wrench on each side.
* Flip the chain tensioner out of the way, and push the wheel slightly forward without letting it drop. The chain will now be loose, and can be derailed using a wrench. The wheel can now be safely and easily removed.
* Remove the valve cap and nut, and you are ready to pry off the tire. Pry the tire away from the rim with your first tire iron, and then begin using the second one to pry the tire off, starting where it is just overhanging the wheel and working your way around.
* Remove the tube, and inspect it and the tire for causes of the flat. Start at the valve and work your way around to find any nails or debris that might have caused the flat.
* Get your new tube, and put just barely enough air in it to get it into a round shape. Remove the valve cap and valve nut, and leave the washer on - you want it on the inside of the rim. Place the tube on the rim.
* Get the tire seated back on the rim, with the tube rested inside it. Put the tire back on using the tire iron, taking care not to pinch the tube.
* Inflate the tube.
* Check to make sure the tire is seated. The bead of the tire should make a line closely around the rim - if it's beneath the rim or too far above it, deflate and re inflate until it is seated properly.
* You are now ready to put the wheel back on the moped. Take special care to align the brake with the bolt meant to fit into it.
* Align the back wheel using the chain tensioners, tighten the axle nuts, and reattach the brake cable.
Following these steps will get you and your moped back on the road.