Clamp the rim and insert the rod through the hub into the hole beneath, then spray the bead generously with liquid soap or tire lube.
Insert the flat end of the lever between the upper
and the rim.
Lever the tire bead off the rim and lay the bar flat across the wheel, slide the bead off the rim by pivoting the lever on the rod.
Continue around the rim until the top bead is off. Repeat with the bottom bead.
Some tires' lower bead will come off by hand after a little prying with the bar.
Remove the rod and the old tire.
Spray both beads with liquid soap (diluted 1:4) or tire lube, then shove the lower bead onto the rim. It will often go on with no tools, but a bit of prying may be necessary. Pay attention to the arrow on the tire. Line the painted dot on the tire sidewall up with the valve - this is the lightest spot on the tire, and the valve is presumably the heaviest spot on the rim. But not always.
Start the top bead by hand, then apply a small clamp to keep it from slipping off the rim. Or you can use a tire iron with your third hand.
Hook the curved part of the knuckle end of the bar over the rim, pivot the bar on the center rod, and work the bead onto the rim.
Remove the wheel from the clamps before inflating the tire or it'll grab the clamps and you can't get the wheel off them.
Seat the bead of the new tire on the rim before installing the valve core - sometimes the core doesn't allow air into the tire fast enough to inflate an unseated tire.
Somewhere between 20 and 40 psi you'll hear two loud pops. That's the bead seating on the rim. This may not happen on tube-type rims, btw.
If you're using a tube, powder it (baby powder) before installation. Once the bead has seated, deflate the tire and reinflate at least two more times to let the tube wiggle around inside the tire until it's straight.
Most tires should be balanced before installation on the bike. I use an A frame balancing stand, but it can sometimes be done on the bike if the brakes are removed to allow easy rotation of the tire.
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