Levering the tire off the rim the right way
Okay. Wheel's off, in your hands, not fighting the frame anymore. Now we get the tire open.
This is the step where I see the most damage happen. Pinched tubes, scratched rims, people white-knuckling a screwdriver because that's what was in the drawer. We talked about that a couple lessons back, the levers versus screwdriver thing. This is where that decision actually pays off or doesn't.
Deflate it all the way
First thing, get every bit of air out. Push the valve stem in on a Presta valve, or press the pin down on a Schrader, and squeeze the tire with your hands to force the last of it out. Don't skip this because you think there's "not much air left." There's always a little more than you think, and that little bit is exactly enough to make the next step harder than it needs to be.
Break the bead
Before any lever touches the rim, you want to break the bead loose all the way around. That means pushing the tire's edge away from the rim wall with your thumbs, working around both sides. Sometimes it pops free easy. Sometimes, especially on a tire that's been mounted a while or one that runs tight, you're leaning on it with your palms and it still doesn't want to let go.
That's fine. Keep working it. This part's not glamorous, it's just persistence.
Get the first lever in
Once the bead's loose, take your tire lever, the plastic kind, three bucks a set, and slide the curved end under the bead, opposite the valve stem. Not at the valve. That's low key the part people get backwards, they start right at the valve because it seems logical, but you want to start on the far side so you're not putting pressure right where the valve stem comes through.
Push the lever down so the bead pops up over the rim edge. Then hook the other end of the lever onto a spoke to hold that section up while you move to the next spot.
Work it around, not one big yank
Take your second lever, insert it a few inches from the first one, same technique, pop it over the rim. Now you've got two points holding the bead up. From there you just walk it around the rim, lever, hook, lever, hook, until one whole side of the tire is off the rim.
You don't need to lever the entire tire off in one heroic motion. Most beginners try to muscle it in two moves and end up prying so hard something gives, usually the tube. Small bites. That's the actual technique.
Pull the tube out, gently
Once one side of the tire's off the rim, reach in and pull the tube out. This is the moment to actually look at things instead of rushing to the next step. Check the tube for the puncture, check the inside of the tire for whatever caused it, thorn, wire, glass, whatever's hiding in there. If you skip that check you're just going to flat again in the driveway a minute after you think you're done. I've done that exact thing, first flat I ever fixed for my kids, aired it right back up without checking and watched it go flat again in about thirty seconds. Jackson still brings that up.
The part people mess up with the levers
Here's the thing, when you're prying that bead over the rim, if you feel the lever catching on something soft instead of sliding along the rim edge, stop. That's probably the tube getting pinched between the lever and the rim. Reposition before you push through it. A pinched tube is the single most common flat-fixing mistake I see, more common than the original puncture that started the whole thing.
This is also where I'll say the opinion I hold pretty firmly: tire levers, not screwdrivers, not butter knives, not whatever's on the workbench. A screwdriver's edge is sharp enough to slice a tube or gouge a rim, and it doesn't have the rounded shape that protects the tube while you're prying. The levers cost almost nothing. Just get them and skip the improvising.
A quick aside on chains while you're down here
Since your bike's flipped and the wheel's off anyway, glance at your chain. Not required for the flat fix, but it's a good moment to notice if it's dry or gunked up. I over-lubed a chain once, way too much, dripping wet, and by the end of one loop on the Murdock trail it had turned into this black paste from all the trail dust sticking to it. Learned the hard way that less is more with lube. If your chain looks like that, we'll deal with it properly in a later lesson, but don't go dumping oil on it just because it's convenient right now.
Before next time
Practice breaking the bead and getting that first lever in on a spare tire if you've got one lying around, even off the bike. Getting the feel for how much force it actually takes, without a flat to fix under time pressure, makes the real thing a lot less stressful.