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23 votes

What might cause an inner tube to "behave" flat in a tire?

When you inflate a tube that is not inside a tire, even if it balloons up a huge amount, you are only getting maybe 1-2 PSI (7–14 kPa). A tube that is not constrained by a tire will increase in size ...
Ken Carlson's user avatar
16 votes

Why did my road bike tire patch fail?

Bike shops don't patch tyres because at $60-100 per hour its not worth their time compared to a new tube. Road tubes can absolutely be patched, however its harder with thicker patches - try and get ...
Criggie's user avatar
  • 127k
12 votes

Repeated punctures at the base of the valve stem

The rim hole in the second photo has a clear curve of silver metal. That looks like a sharp burr left over from the drilling process, and it will slowly erode its way into your tube. The solutions ...
Criggie's user avatar
  • 127k
10 votes

What might cause an inner tube to "behave" flat in a tire?

When searching for a tiny air leak, water is your friend. Your leak is tiny, at least at pressures available in a bare tube. Get a container full of water where you can immerse at least a section of ...
fraxinus's user avatar
  • 693
8 votes

Why did my road bike tire patch fail?

My road tubes are definitely harder to patch than my MTB tubes. I also blame the width, but specifically the curvature. Some of my patches are simply too stiff to stay nicely on the tube, while being ...
Chris H's user avatar
  • 60.3k
8 votes

What caused this puncture in my tube?

Your tube has punctured because of a lack of support in that spot. I bet if you examine the inside of your rim, the one spoke access hole at that spot will either have a sharp edge, or the rim tape ...
Criggie's user avatar
  • 127k
8 votes
Accepted

Repeated punctures at the base of the valve stem

It seems the tube has tried to move (probably dragged by tire while braking), and the valve was trying to prevent it from doing that. The result of that is shear stress not only on the part of the ...
Matija Nalis's user avatar
8 votes
Accepted

I put a 700 x 35c inner tube in my 700 x 38c tyre. Is my tyre in risk for a flat?

Any increase in puncture risk from a fitting a 38mm tyre with a tube rated for 35mm (max) is tiny. Don't worry about it. The softness you're feeling is probably simply that you haven't pumped it up ...
Chris H's user avatar
  • 60.3k
7 votes

Repeated punctures at the base of the valve stem

I've had rim that caused punctures like that quite regularly. Covering the sharp edges of the valve hole with tape helped to some degree. Making them less sharp with a file or sandpaper might help as ...
Vladimir F Героям слава's user avatar
7 votes

extremely slow leak in tire

Inflate the tube so it tightens up properly*, submerge it in water and look for air bubbles. That should enable you to locate any holes and/or perhaps a faulty valve. You need some patience, and ...
WornChain's user avatar
  • 2,026
6 votes

Keep getting small punctures on spoke side of tube

You got the next step nailed already. Use an "offset" from the valve to figure out exactly where on the rim is the cause. Then feel around that area for a sharp point or a sharp corner of ...
Criggie's user avatar
  • 127k
6 votes

How can I treat small glass cuts on my bike tyre?

Against glass on roads, there are three measures (pick one or two ;)), and mostly preventive: Puncture Resistant Tires: there are product ranges meant provide additional protection (typically kevlar ...
Rеnаud's user avatar
  • 21k
6 votes

Repeated punctures at the base of the valve stem

As others have pointed out, make sure to have the valve perpendicular to the rim at all times. Secondly you could try make some improvised padding around the rim hole, especially if the edge in any ...
WornChain's user avatar
  • 2,026
6 votes
Accepted

List of most common types of bicycle tyre flats (tube tire flat puncture)

Blowout is where the tyre failed at holding pressure, and the tube was left unsupported. These holes are often missing small parts of tube, and could have radial tears going outwards. Often sudden, ...
5 votes

Why did my road bike tire patch fail?

I followed all the steps: found the leak, No you didn't. This list does not contain all the steps. roughed up the surface of the inner tube around the leak You don't rough up the surface. The ...
juhist's user avatar
  • 19.7k
5 votes
Accepted

Is it generally safe to ride on with a puncture like this?

You got home okay and the tube did not blow out. So your choice worked fine this time. The other option is that it blew out as a sudden puncture immediately loosing all pressure and dropping your rim ...
Criggie's user avatar
  • 127k
5 votes

How can I treat small glass cuts on my bike tyre?

With some kind of protection inside the tyre, the best you can do is check the tyre occasionally. The tyre doesn't have to be airtight (assuming you're not running a tubeless setup, and it sounds like ...
Chris H's user avatar
  • 60.3k
4 votes

What is the best old tube plus current tube or current tire plus old tire combination if I want to puncture proof my bike or can I use three of them?

Humans have very low power to weight ratio compared to cars. It might be possible to make a bike tire that is practically impervious to road hazards. However, it would be extremely slow, heavy, and ...
Weiwen Ng's user avatar
  • 32.8k
4 votes

Why did my road bike tire patch fail?

One last thing that others have not mentioned: in the past, I didn't spread the vulcanizing fluid over a wide enough area, so I had some patch jobs fail. You want the whole patch to be covered in the ...
Weiwen Ng's user avatar
  • 32.8k
4 votes

Rear wheel deflating instantly after pumping

Find what caused the hole and fix the issue. Remove the thorn or glass, etc. Check this answer for how to find the flat cause. Patching is cheaper but requires a little skill. New tube is easier and ...
David D's user avatar
  • 22k
4 votes

List of most common types of bicycle tyre flats (tube tire flat puncture)

There aren't necessarily standard terms for every scenario. A pinch flat, for other readers' reference, is when you hit the tire hard, and the rim slices holes in the tube. There are two linear holes, ...
Weiwen Ng's user avatar
  • 32.8k
3 votes

What is the best old tube plus current tube or current tire plus old tire combination if I want to puncture proof my bike or can I use three of them?

I do not think that an old tube over the new one would protect much at all. If a thorn manages to go through the tyre, it will puncture one tube layer almost as easily as two tube layers. You can buy ...
Vladimir F Героям слава's user avatar
3 votes

Keep getting small punctures on spoke side of tube

The tube could abrade on any sort of irregularity, even something that got loose inside. The first things you should do are: map the location - this should not be hard if you are patching or at least ...
Dan Gao's user avatar
  • 420
3 votes

Is it a good idea to use a Presta-to-Schrader adapter and Schrader mini pump if you have bikes with both valve types?

Those who ride more-than-one bike might have different valve types between bikes. My solution is that every regularly ridden bike has a toolkit on it, with 1/2/3 spare tubes to suit its wheels and a ...
Criggie's user avatar
  • 127k
3 votes

Is it a good idea to use a Presta-to-Schrader adapter and Schrader mini pump if you have bikes with both valve types?

I think it’s a very bad idea to use adapters, especially in the repair kit that is used on the road side. Adapters can be lost. Even mini pumps can support the two kind of valves directly. That is for ...
Rеnаud's user avatar
  • 21k
3 votes

How can I treat small glass cuts on my bike tyre?

For a moderate hole/cut in the tire, I would patch the inside of the tire because the cut can expand over time. The patch will arrest this some. Patching the inside of a tire is fairly straightforward....
TacoTanium's user avatar
2 votes

How can I treat small glass cuts on my bike tyre?

If the cut is small, and you've removed whatever sharp make the cut, then just leave it. Any cut under 1-2 millimetres should be fine to leave, as long as cut does not show any threads tube is not ...
Criggie's user avatar
  • 127k
2 votes

Unused puncture repair patch - what's its useful shelf life?

I bought 48 puncture repair patches from aliexpress in 2017. From about a year ago (or 5/6 years after purchase) I have found that I don't seem to be able to repair punctures anymore, whereas I could ...
Timothy Takémoto's user avatar
2 votes

How can I treat small glass cuts on my bike tyre?

I have used superglue with some success on cuts in a tire. If a cut is small and not very deep I ignore it. If the cut is larger, but not too large, the superglue method can have some success. I have ...
Ted Hohl's user avatar
  • 6,437
2 votes

Why did my road bike tire patch fail?

I've had terrible problems in the past when the cement gets too old and loses its potency, whether sealed or not. But I would guess you might have run into that if you've done a lot of patching. ...
Dan Gao's user avatar
  • 420

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