Tori Bortman is here to help you
gain confidence in patching tubes.
(Photos: Daniel Sharp)
Most folks don’t like to patch tubes for many reasons: “It takes too long,” “it never holds,” or “I just carry a new tube.” Carrying an extra tube will only get you through one flat per ride, and occasionally the new tube will fail. I’m always a fan of carrying a patch kit — and knowing how to use it can make the repair quick, easy and practically pain free.
A standard patch kit comes with three things: a patch, some “glue,” and a small piece of emery cloth. All of these are of equal importance in the success of the patch holding. More on this—and pre-glued patches—later.
A properly patched flat is as reliable as a new tube! Even if you don’t patch on the road, bring your bum tube home and repair it for the next ride. Ready? Here we go…
Step 1: Find the Culprit
Over inflate your tube so that it looks slightly misshapen. The tube is basically a skinny balloon so it can take a little extra air. Put it to your ear or against your cheek to listen and feel for the air escaping. A hole one the outside of the tube (opposite of the valve stem) means something came through your tire like glass or metal. A hole on the inside of the tube is most likely caused by your rim strip (half moon shape) or a pinch flat (small slit or two next to each other, sometimes called a “snake bite”). Occasionally the hole is too small to find. In this case, you’ll have to wait until you’re near water and try submerging the inflated tube to find the air escaping.
Step 2: Prep the Area
Deflate the tube of any remaining air. Using the edge of the emery cloth or sand paper, mark a 1-inch square around the hole(s). This will give you a point of reference for where the hole is because you soon won’t be able to see it any longer, and you want to know where to put the patch.
Next, using the emery cloth rough up the area inside the square you marked until it gives you a dull surface with lots of rubber debris like from a pencil eraser. Taking an extra 30 seconds to do this right will make the next step quick, easy and make for the most reliable patch.
Step 3: Apply the Vulcanizing Fluid
Vulcanizing fluid (boy, I love saying those words. Vulcanizing. Fluid. Yes.) is your “glue”. The difference? Glue holds two things together. Through a chemical reaction, vulcanizing fluid allows a rubber surface to accept and bond to a new piece of rubber, a.k.a.: the patch, making it like new.
Apply the vulcanizing fluid inside the square in a thin but even layer all the way to the edges. This might seem like a much larger area than you need, but it’s easy to under estimate how big the patch is, so go big. Use the tip of the tube to spread it evenly—the dirt and grease from your fingers can interfere with the vulcanizing process. The more the surface has been roughed up the more material the fluid has to interact with and the quicker it will dry, usually in under 30 seconds if done properly. Because it’s a chemical reaction, blowing on it or holding a lighter to it will not speed things up. Only Step 2 can do that!
Step 4: Let the Vulcanizing Fluid Dry
The fluid must be completely dry before you apply the patch. The tube is ready when the glue goes from looking shiny-wet to matte-dull. While you wait, clear debris from your tire or fix other issues that caused the flat.
Step 5: Apply the Patch
Peel the foil from the back of the patch and apply the rubber side down. Press down firmly rubbing from the center of the patch outward. You can peel the plastic layer away or leave it on. If you try to remove it and the patch comes off with it, you didn’t make get a solid contact and should start over. If you’ve followed these steps, chances are this won’t happen!
Step 6: Check the Seal
Finally, over inflate your tube again to make sure its holding air. Nothing worse than finding out your patch didn’t hold after you put the wheel back on your bike!
A word about “glueless” patches.
Patches advertised as “glueless” come with the vulcanizing fluid pre-applied to one side. You still need to follow steps 1, 2 and 5, and be extra careful to keep the sticky side of the patch clean before you apply it to the tube or it won’t hold.
I don’t recommend these because I’ve found that they’ve failed more often and sometimes break free later or stick to the inside of the tire. If you like them and have had success, stick with (ahem) what’s working for you.
— For more tips and tricks from professional mechanic and maintenance educator Tori Bortman read previous Optimize Your Ride columns. Learn more about Tori and consider taking one of her classes at GraciesWrench.com.
So wait, all these pictures of punctured inner tubes were taken by Daniel…..Sharp?
“Re-vulcanize my tires, post-haste” – Best Mr. Burns Quote Ever
Tubes I can patch okay. What I REALLY need is a reliable way to patch a slice in the tire surface — assuming it hasn’t damaged the underlying cords.
You can try and use the same fluid to bond the tire back together, but you may not have much success. Because the pressure is so high the tire will naturally want to split back open. Your best bet is to patch it from the inside with either a tire boot or use a piece of old inner tube and vulcanizing fluid.
Hope this helps!
just find something to boot it, patches actually work well for this, and then some superglue on the outside of the tire.
I have to say the majority of patch jobs I have done have not held air. Maybe it was my technique?
How about if the tube is punctured on a seam (which seems to happen a lot to me). Seems like those situations are pretty much unpatchable.
Unless the hole is very big (like a blow out) or at the edge of the valve stem, most are repairable. It might be that you weren’t roughing up the surface enough for the vulcanizing fluid to work, or you missed the hole with the patch, or you needed a bigger patch.
Hard to say with out seeing it, but I’d give it another go.
If you’re getting frequent holes at the valve stem, stop using the valve stem washer. This often causes more flats than it prevents.
This is where I use the “pre-glued” patches. They work great for the inner side of the tire. I have not had much luck with them for patching tubes, however.
When i was young and poorer, especially if i cut a new tire, i would take thread and stitch the tire up ! yes pliers and thimble required. and soapy water. then patch over that.
But Vulcan was destroyed in the latest Star Trek film, where to they get more of this mysterious fluid from?
`s ok, I know a Feringi who’s been hording a stockpile as a hedge against Vulcan’s lack of a planetary defense fleet. You’ll pay a steep markup though.
Agreed with the note about pre-glued patches. Done it once, it didn’t hold and I was flat again 24 hrs later. Going back to the old fashioned glue in a tube.
The best tip I learned regarding patching is to bend the patch in half once it’s on the tube and dried. This cracks the plastic it’s attached to and allows you to peel it off from the middle as opposed to the edge, eliminating the risk of pulling the patch off, or pulling it up enough to let air out.
i keep two tires – one that’s been patched and is awaiting my bike, and the other on the bike. when i get a hole, i patch the one on the bike and swap them so i always have one ready. what a money saver!!
A couple of additional tips:
1.) Mount your tires so that the pressure rating imprint is aligned with the valve stem. That way the number you need is easy to find when you need it. It also lets you maintain a relationship between the positions of the tube and tire, allowing you to:
2.) Check the inside of your tire at the location of the puncture in your tube. Carefully run a fingertip over the inner surface to make sure the source of the puncture isn’t still lodged in your tire. I got at least two flats off the same fine whisker of wire before I learned this one. When you find the offending object:
3.) Carry a set of tweezers along with your patch kit. Useful for extracting tiny sharp things from your tire. And:
4.) Inflate your tube slightly before reinstalling it. This verifies the integrity of your patch and will also highlight a possible second puncture on the inner side of the tube if the thorn or whatever was particularly long and/or you rolled a few turns on the flat before stopping.
This looks pretty much like what I’ve tried doing, except I always get slow leaks. I hear the same from other cyclists. Maybe they’re not as effective at higher pressures, like 120 psi?
The patches should work even at 120psi. Mine usually fail when I don’t get glue all the way to the edges or I don’t rough the surface/apply enough vulcanizing fluid.
I try that first before you give up!
And not run 120 psi. Most pros only go up to about 100. VeloNews did a really good article on it a while back.
My employer (Hewlett Packard, Corvallis) added some new bike racks a few months back in a very central location. We were able to get some funding to buy a nice floor pump, some tire levers, and an assortment of tubes to keep in a kit at those racks. Replacement of the tubes is on the honor system. I have heard from several of our bicycle commuters who have used the pump to top off for the ride home. The crowning touch in all this is that the guy who does approvals for chemical usage (standard practice for big companies) on our site is a regular bicycle commuter. Without any prompting, he gave us an approval for the vulcanizing fluid (yes, I like that phrase too!) in the popular REMA brand patch kits so people can patch rather than replace if they wish.
Just a little hint for any other businesses that want to support/encourage bicycle commuting.
Thomas- I ride exclusively with high pressure 700 x 23 and am able to regularly patch them successfully (ie able to ride them for the duration of the life of the tire with no leaks). If you follow the instructions above to a tee you should be good to go.
I’ve had great luck with GOOP. Just put it on the cut and let it dry. On occasion I’ve also put a patch on the inside of the tire as a “boot” but the glue keeps it from coming out if/when I have a flat.
I only know Tori through acquaintances, but she is super rad. I am so happy to hear she’s doing well! And patching up tubes is sustainable. economical, and AWESOME.
I recommend getting puncture-resistant tires so you only rarely get flats! I have Schwalbe Marathon tires, and have gotten no flats in three years of daily riding. I don’t even carry a flat kit anymore for rides within Portland.
+1 on the Marathons. I just put my first set on this summer. My commute is on a state route with a no-spray goathead farm on either side. The last several years, it’s been about 1 flat per week this time of year, even with kevlar strip tires and extra Mr. Tuffys inside. I’m not going to comment in detail on the Marathons without a sturdy oak table to knock on, but I would buy them again.
You can also buy kevlar-lined puncture-proof tires. 3 years and 0 flats so far!
Lots of good advice here. I’ll add that it can never be stressed enough to make sure that the area to be patched must be clean and well-scuffed. I think the reason that glueless patches fail is because of residual talc and failure to scuff the tube.
I carry a spare tube and a patch kit. If I ever get a 2nd flat on the same ride, I can patch one of the tubes.
One of my earliest tube patching memories is of my grandfather using a hot patch on a tube from his ’59 Chevy wagon…
agree: the patch kit is for the second flat
Out of about 15 patches I have put on tubes, 1-2 has failed. Only slowly and these were only on the first few patch jobs for me. If its on the seam, sand more.
-Be careful scruffing too much on thin tubes, you’ll scruff in a bunch of tiny holes.! I use rubbing alchohol also and light scruff
-I almost never use rema type patches. Maybe i got a old batch of them (patches do have limited life) too many negative experiences. IME, the best patches are the thin cheap ones, I then cut them out into a small square maybe 5mm x 5mm also chamfer the corners. You have to of course then know exactly where your hole is (and the hole can’t be too big..). I am quite aggressive rolling/pressing the patch into the tube after initial laydown.
-recently gone tubeless Whoa sweet. Marathons, like 700×32 /35 work absolutely brilliant tubeless. Rolls really nice and feels more efficient… Yes kevlar bead. don’t go over 45/50 psi. And you need some know-how and a little patience to get them to work. Rim tape prep and mount has to be perfect. I am using stan’s 355 rims. Currently runnning conti contact, 700x32c but actual measured was only 28.6mm 🙁 wide, wire bead. but managed to hold on the rim at 60 psi ! Rode last fri to the coast on them along the nehalem river. did great on gravel ! but mainly they are my commutters now..
I have had success with a tire liner: a long strip of plastic that goes between the tube and tire. twice I have worn a hole in my tire. Instead of the tube popping out like a balloon, the liner holds it in check and allows me to ride on for a few miles to home. I have also had like one flat in 2 years. But I do carry a kit and tube for fast swaps (on my way to work) or leisurely patch repair on my way home.
carefully shave off the small “mold mark” or thin line left on tubes. sometimes interferes with the patch. use a disposable razor, works great.
the use of baby powder to install a tube whether it be patched or new my tip…put tube in a bag, add a little powder and give it a shake then install.
You can also use liquid or spray – work very well for small holes. http://www.open-info.eu/spray-do-latania-detek-roweru-patch-spray/
Also shine a bright flashlight inside the casing of the tire this way you can locate any pieces of glass stuck inside, also run some tissue inside the tire it will tear on any sharp objects make them easier to find