The bicycle puncture, it’s one of those things that seems to happen at the worst times. Your kids are all ready to go ride, but you see the dreaded flat tire, or you’re halfway home from work and one strikes.
Once you know the process, fixing a bike puncture is something anyone can do plus, you can save a paying a bike shop to do it for you!
To fix or replace your tube?
This would be a common question people would ask themselves but usually, it comes down to the situation.
If you get your puncture fixed at a bike shop, they will usually replace the tube instead of fixing it since it’s the reliable and quickest way to fix them in a retail or high volume situation. Also if your out riding it easier to carry a tube with you, and swap one out on the go.
At home and where time is not an issue, patches work great and can save a lot of money, especially if your kids bang their back wheels going up curbs constantly! Also, it’s handy to fix things like wheelbarrows and trolleys since the tubes are harder to find since the process is exactly the same.
Types of puncture repair kits
You will come across two main types of kits:
- Standard glue patch kit – This is the classic type and the most commonly used. Everything you need comes complete in a set and there are multiple sized patches for different tube sizes.
+ Pros – Great, permanent solution when glued down correctly and works better for higher pressure tires
– Cons – Takes a bit longer to apply and you might need to practice first if you have never glued up a patch before
- Glueless patch kits – These are very simple to use and require minimal fuss, once the area is prepared, simply press on the self-0adhesive patch over the hole and your good to go. There are multiple patches in one kit and some kits may have different sizes patches as well.
+ Pros – Very quick to apply, great if don’t want to carry a tube with you
– Cons – Not the best for all tires, may fail over time
Above are the usual contents of a puncture repair kit, as well as the glueless patches which are sold separately.
- Patches of various sizes depending on how large the hole is
- Sandpaper or small rasp to roughen the tube to help the glue adhere
- The vulcanizing solution (patch glue)
Whats the chalk for in a puncture repair kit?
Some kits will contain a small block of chalk, this is used to stop the fresh patch sticking to the inside of the tire. You grate the chalk on the sandpaper over the fresh patch just before re-fitting the tube.
Stopping the glue tube from drying up
It’s common for the opened glue to dry inside the tube, you can avoid this by squeezing out all the air from the tube right before screwing the cap back on. Next time you come to use it, you should be good to go and not stuck with a dried out glue tube.
How to patch a tube – The process
1 – Remove the wheel from the bike
If you have V-Brakes, unclip the brake cable by squeezing the arms together allowing you to remove the V-Pipe from the holder, if you are unable, just loosen the cable anchor bolt to allow some cable to be pulled out.
You may need a spanner to undo your wheel nuts, or if the wheel is quick release, simply pull the lever open and thread the opposite nut undone a handful of times.
A tip with rear wheels – shift your chain into the very smallest cog at the back, this way when you refit the wheel you just line the chain up back on the smallest cog, centering it and making it less of a hassle.
Breakaway the tire bead
This can be extremely helpful if the tire has been on a long time. With your hands, push the tire bead (base of the tire) away into the center of the rim, do this all the way around on both sides.
What this does is allows the tire to float free on the rim and in most cases allows it to sit down in the rim making it far easier to get your tire levers in to pry it off.
Remove tire with tire levers
Now that the tire has been freed from the rim, you can start working your way around with the tire levers, most levers should have a slight hook on the end to grab the tire while the other end has a hook which handily clips around a spoke as pictured.
Once the first one has started, use the opening next to the first lever and work your way around, prying the tire upward and sliding the lever around the bead to remove it. Once one side is off you may be able to pull the other side off by hand, if not, just repeat the process on the other side.
Check the rim
It pays to quickly check the inside of your rim for damage or things that might have caused the puncture.
The green tape here covers the spoke holes and stops the tube from pushing into the hole and puncturing. If the tape is damaged or has shifted, exposing the open spoke hole it may have been the cause of your puncture and not your tire.
Your tape should be straight and even as above, if not, re-align it or purchase a replacement.
Check your tire and locate the hole
Now your tire has been removed, with the tube inside inflated it so it fills out the tire, this allows you to feel, or hear where the hole is.
Alternatively, remove the tube completely and inflate till firm, then dip the tube in a bucket of water to check for air bubbles, also check the valve at the same time.
Tip – Before you remove the tube, mark the location of the valve on the tire so you can reference the puncture location after dipping it in the water making it quicker to find the object in the tire.
Checking the tire – Run your fingers around the inside of the tire, visually check the inside and outside of the tread. Sometimes the culprit can be hard to find so just take your time and even go around it multiple times since it will save you the hassle of missing something and having to repeat the process
Tip – If you can turn the tire inside-out, this is easier on bigger tires and allows you to run your whole hand on the inside, also it helps to expose small objects which you may have missed easier.
Mark the hole
Mark where the hole is with a biro, or crayon if your puncture kit included one. The hole can be quickly lost and marking it makes life a lot easier once it sanded and you come to put glue on it.
Sand the area
With the small sandpaper, roughen the surface of the tube until it’s even and clean. If the hole is right on a seam, the sandpaper helps to knock off the top of it and levels out the surface for the patch.
Make sure the tube is clean and free for any oil or dirt since these will affect how the patch will stick and seal your hole. You can clean the tube after sanding with isopropyl alcohol or the alcohol wipes if you have some.
You can just see the outline of the circle marking the holes location above.
Pick a patch and apply the patch glue
As there are a few different sized patches, pick the one that is appropriate for your tube. The smaller, round patches work best on smaller diameter tubes while the larger patches are good for bigger volume tubes.
With your patch selected, apply a layer of glue around the area of the hole, use a clean finger or the foil of the patch to quickly spread it around evenly. It shouldn’t be globby or lumpy, just an even spread of glue.
Give the glue some time to dry off, this usually takes around 2 – 3 minutes. You can tell the glue is ready when it appears as a dull finish when it’s still wet there will be glossy patches visible indicating it’s not ready.
The glue above is just about ready, it’s dull up the top but still drying down towards the bottom.
Peel the foil backing away from the patch by holding the plastic film. Do not try to peel the plastic film away while the patch is on its foil backing.
Apply the patch
Stick the patch to the glue and firmly press it down especially around the edges, repeat this for a minute or so. You can check how well the patch stuck by gently lifting the plastic film, the edges should be firmly stuck down and not come away.
Tip – If the patch is not sticking, make sure you give the glue adequate time to gas off as it partially melts the tube rubber which is how the patches stick to the tube as they do. Also, make sure not to touch the back of the patch since oils in your skin will affect the patch.
Leave the clear plastic film on the patch, this stops the exposed glue sticking to the inside of the tire. Over time the film will break down and fall off.
For glueless patches
If you are using glueless patches after the area is sanded simply peel a patch off and stick it to the tube. Press down firmly and make sure all the edges are well stuck down.
Inflate the inner tube
Gently inflate the inner tube to give it shape, this helps with installation and helps avoid pinching the tube or creasing it when it’s put back inside the tire.
Tip – Don’t put too much air in the tube, only enough to hold its shape. Too much will stress the fresh tire patch causing it to fail.
Fit the tire
Fit one side of the tire onto the rim. With the other half open, start by putting the valve into it’s hole and working the tube inside the tire, if the tube gets difficult towards the end, let some air out since the tire squashes the tube down in volume.
Check to make sure you have put the tube inside without any creases or bulges by pulling the tire open and looking inside.
Fit the last half
With the tube installed, start opposite the valve and pull the tire bead over the rim, working your way towards the valve. You will likely get to a point before it becomes difficult and you need to use levers.
Tip – Use the curved channel running down the middle of the rim to make fitting the tire easier, as you work your way around, push the fitted tire bead towards the middle of the rim while pushing the tire on with your thumb. This allows the tire to move on the rim making it easier to seat it.
If you do need to use tire levers for the last bit, push the lever inside the smallest amount possible, this keeps the risk of pinching the tube low. Go slowly and two at a time to gently work the bead onto the rime.
Push the valve
With the tire on, push the valve as far as you can inside the rim without losing it, then pull it firmly down, repeat this a few times.
This pushes the bulge where the valve connects to the tube inside the tire, this stops the valve interfering with the tire on inflation which can cause it to seat unevenly and expose more tire bead around the valve area which can be unsafe.
Check the fit
The last step before you inflate is to visually check the tube is inside the tire and not trapped between the tire and the rim. Push the tire away from the rim with your thumb, you should only see the inside rim tape. If you can see the tube sticking out, use a tire lever to gently work the bead and allow the tube to pop inside the tire.
If the tube is left exposed, it will likely puncture when inflated and affect how the tire sits on the rim.
Inflate and re-fit the wheel
When inflating the tire it’s best to do it slowly and check periodically how the tire is sitting on the rime.
Some tire/rim combinations can be very loose or very tight so pump a bit, check the tire is sitting properly on the rim, pump some and repeat until it’s up to pressure, checking as you go. This is the safest way.
Once the wheel is in the bike, spin it and eye the tire as the wheel rotates, if there’s any large bulges or wobbles this means the tires not seated properly.
Once you fix your first puncture and figure out how the patches work, it’s usually not too much of a hassle, the worst part is getting the wheel out of the bike.
So if your kid’s bikes have flat tires or your own for that matter, maybe have a go at fixing your own bike puncture, it might just save you paying someone else to do it.
Get in touch below if you have any more tips or questions.