Bike Wisdom and Rants

POP, Psssst, Shaplunk, Shaplunk, Shaplunk: So You Have a Flat Tire


It’s bound to happen. You are on an enjoyable ride, The sun is high in the sky, trees are full of color. Your bicycle is flying down the road or trail. The world zips by, you pound out a perfect pedal stroke. Life is good. And Then, POP! Psssst…, shaplunk, shaplunk, shaplunk. Your tire has gone flat. Rats!

The good news is, you’re ready. It’d be foolish not to be right? Last time you were at the bike shop and the mechanic showed you the bike maintenance gear, you got everything you need. Whew, what a relief. Now, all you have to do is fix the flat. This is where a lot of cyclists have trouble. Everyone should be ready for a flat tire on their bicycle. Because as much as we would like it to, hope does not keep tires inflated. And flats are going to happen. And as soon as it happens, you have to stop your bike.

I’ve seen way too many people ride all the way to the front door of our bike shop with flat tires only to tell me that they have been riding several miles on a flat in order to get to the shop. Don’t do that. This often results in damage that cannot be repaired. It can ruin the tire, the tube, the wheel and (most importantly) it can injure you! So stop.

Now, have a look at the tire, is there anything sharp sticking out of it? I’ve seen just about every sort of thing that causes flat tires: nails, glass shards, little pieces of metal, thorns, briars, razor blades. I even found a tooth stuck in a tire once. Cool right? But usually, it’s something small, ferociously sharp and less ominous than a tooth. So let’s figure out what’s caused the flat. And be careful, it may be sharp.

Begin by looking over the center of the tire as you turn it slowly. Then, work your way around toward the sidewalls and eventually, inspect tire where it seats into the rim. Look for sharp shards sticking out of the tire, a hole in sidewall or blowout damage to the bead-seat.

Any sharp stuff has to be removed but take care on two details here. Don’t assume that the one you found is the only one. If you ran through a debris field (common in the Raleigh, Wake Forest, NC area) you may have numerous culprits. Best to find and extract all of them. In addition to this, take care to never simply throw the sharp object back onto the bike path. It’s just going to cause more flats for other folks. Better to throw it into the trash or stow it somewhere in your gear until you get near a trash can.

Or maybe there is no sharp object. Is it the sidewall? This aspect of the tire tears easily -especially if it’s old. Even a new tire can catch the side of a rock or curb though and blow right out. The fact is, if your sidewall blows out or if there is damage to the tire bead, you are going to need a new tire. And I’m guessing that you didn’t think to bring one of those on your ride.

If though, you find no thorns or shards or razors (or teeth) sticking out of the tire and the sidewall seems fine, you may have run over something that punctured the inner tube and was  immediately ejected from the tire. Or, and this is pretty uncommon, you could have a problem with the bead of the tire just not being seated properly. But you can only know for sure by removing the tire. It’s a good thing that you brought your emergency maintenance kit just like the guy at the bike shop told you to do.

Or didn’t you? If not, it’s a good thing you brought the cell phone or good walking shoes. But let’s be honest, bike shoes are not good walking shoes. You’d better call Uber. What? Forgot the phone? Are you kidding me? Okay, go ahead; use the emergency money to use the payphone. Wait, do they still have those anymore? If you can’t find a phone and you are too far from home to walk (or your shoes aren’t up for it), you have entered the Samaritan zone and you are now at the mercy of the good will of others. I’m sure you’ll make it home and I am sure that next time you venture out on a beautiful biking day like this; you’ll have a flat tire kit.

On the other hand, if you did bring a flat tire kit, let’s fix the flat! Go ahead and remove the wheel from the bike and then the tire and tube from the rim. If you don’t know how, then you are in over your head and I recommend following my former advice (cell phone, pay phone, Uber, Samaritan, good will and all that). In removing the tire, you may need those plastic levers you got from the bike shop but I recommend making a first attempt without them. It’s always smart to just use your bare hands to pull the tire off the rim. The tire levers are helpful in a pinch but sometimes they can damage the tube or tire and to be honest, the last thing you need is further damage to the bike. You’ve been through enough already.

Before I remove the tube though, I like to mark the tire alongside the valve (or make a mental note of its position). This way, if I find a protruding object inside the tire, I will know right where the hole is on the tube. Now, feel the inside of the tire for any sharp objects. Careful not to cut your fingers on them! If it’s there, remove it. The location of the shard or thorn in the tire, will be the same place you’ll find the hole in the inner tube. Can’t find it? No worries. Whatever caused the flat may be somewhere behind you on the trail and you’ll never see it again (Unless you ride home that way. So don’t ride home that way).

The easiest way to get going again is to simply replace the tube. Just put the old one in your pack or jersey pocket (you can throw it away later or take it hope to patch as a spare), set the new tube inside the tire -taking care to not have any sections folded or twisted. Then, reinstall the tire on the rim. Use the plastic levers only if you need them and only while getting the last little bit of the tire back on the rim. Always install one bead of tire completely on one side. Then, install the other. Then, carefully re-inflate the tube a little bit, make sure your tire is evenly set into the rim. Finally, continue inflating all the way to full pressure. You are ready to ride.

Didn’t go for the spare tube option? Then the patch kit is going to get you home. It’s either going to have a few heavy duty stickers or it’ll have a combination of patches, glue and something scratchy (a metal scratch pad or sand paper). The sticker-style patches are simple: make sure the surface is clean and clear or debris or water and center the sticker over the hole. It’s a pretty strong patch that should at least get you home but could maybe even last for years.

If you have the glue-patch kit. You’ll want to make sure the area to be patched is clear and clean, then rough it up with the scratcher pad and coat it with a layer of the glue. Don’t put the patch on right away though, The glue needs to dry first. You’ll know it’s dry when its surface gets milky white. Then, you’ll simply lay the patch in place and reinstall the tube. The tube can now be aired up and the bike ridden immediately. This kind of patch can last for a long time. I had a road bike once who’s inner tube had half a dozen patches. I kept getting flats from debris in the road and didn’t want to have to buy lots of inner tubes. So I just kept adding more patches out of sheer bike nerdy-ness. And that single inner tube lasted for years. If they are done correctly, the patches are pretty dependable like that. Just patch and go. But most people prefer to install a new tube.

Of course, It’s not always this simple. But it almost always is. So many different things can cause flat tires that it can be one of the most frustrating things to deal with in all of cycling. But being prepared should make it much less frustrating. And there are so many products available to deal with flats that the hardest part of preparing for such occurrences is just narrowing down the choices and distinguishing between needs and wants. The selection of pumps alone seems endless. Should I get a CO2 pump, a micro-inflation, a frame pump? I think that the best approach is to ask a bike mechanic. Then head to the bike shop to the See what they have.

Prevention though, is the primary factor in flats. Nothing prevents flats as well as good tires and correct air pressure. But since flats are at least slightly inevitable, be prepared.

I’ll see you out there. And if I see you trying to fix a flat don’t worry, I’ll stop to help.

The Bike Guy