How to detect the air leak
The Bubble Test
The first step in repairing a leak is locating exactly where the air
is escaping from your tire. The bubble test is the best way to pinpoint
the exact location of a puncture. You can find multiple leaks with this
type of test too, which is a common problem with some types of thorns.
However, the bubble test is not always a reliable way to locate leaks
between the tire bead and the rim strip. Air that leaks from anywhere
around the circumference of the tire bead will almost always come out at
the inflation valve. The spoke nipples typically seal well enough that
air will not make it through the spoke holes.
Here's how you do it:
Immerse the tire and rim in water. You need to
have a fairly large container for the water in order to submerge the
full tire and rim for 4 or more spoke holes at a time. A bathtub, sink,
large utility basin is ideal. You will be able to find the puncture by
observing where air is bubbling from the tire.
If an initial bubble test shows that the leak is inside the rim
cavity (bubbling through the inflation valve clearance hole in the spoke
bed of the rim) and you want to isolate a leak location, then seal the
valve outlet area with an oil based clay or other non-permanent caulking
material and try to force the bubbles out of the spoke holes near the
leak. It is generally easier to substitute parts to cure this type of
leak. You can't perform a bubble test on a tire that's not mounted to a
rim or if the tire leaks air too fast to immerse.
The Aural Test
Another way to find the location of a leak is to inflate the tire and
listen for the distinct sound of air escaping. Not all leaks are
detectable in this way since you need to be in a pretty quiet
environment in order to hear it. You can detect some internal leaks by
slowly rotating the wheel as it is partially submerged in water (about 6
inches deep). As you rotate the wheel and an internal leak is
submerged, you will hear the sound caused by the bubbling water inside
the rim. You cannot see an internal leak, but you can find its general
location in this way. This can be helpful when you are trying to find a
leak between the tire and rim strip. If you hear a puncture leak in the
tire, another way to confirm its exact location is to test the likely
spots with saliva. If you cover suspected hole with saliva, the noise of
air escaping will get louder and will also be visible.
If you have a tire that leaks but you can't inflate it enough to use
the bubble test or hear the leak, you have to substitute components (rim
strip, valve, or tire) to isolate the cause and repair the leak. You
can replace everything that might be leaking air to fix it fast, or you
can replace things one at a time to find the defective part.
Leaks at the valve
Remove and inspect the valve. If it is damaged, it will need to be
replaced. If you are out on the trail, you will need to install an inner
tube to complete the ride.
Leaks under the tire bead
This type of leak requires new parts or using an inner tube. In an
emergency, a caulking adhesive or thick, non-hardening adhesive (such as
traditional sew-up tire glue) can seal up a small leak between the tire
and rim strip temporarily. This method should only be used as a
temporary measure to complete a ride when spares are not available.
Leaks through the tire casing
Occasionally you might have a leak in an otherwise serviceable tire
casing that allows air to escape at an unacceptably high rate. A bubble
test will reveal the location(s) of the leaks. Normal patching methods
will work, or a fluid tire sealant such as Super Juice might reduce the
leak rate too. If sealant is used, you should hold the wheel sideways
(rotational plane horizontal) to allow the sealant to cover the leaks.
Regular patches from a standard patch kit will work on the inner
surface of a tubeless tire. "Glue-less" patches will work too. The same
rules for patching a tube apply here: the inner surface of the tire must
be clean, dry and abraded lightly to be patched reliably.
How to temporarily repair a Tubeless Tyre puncture
For repairing a tubeless tyre puncture, you will need the following equipment:
1. Pliers - To extract the puncture causing object
2. Smoothening tool - To ensure that the sides are smoothened out for the puncture strip to be applied.
3. Puncture Repair strips
4. Puncture Strip Insertion Tool
5. Knife/Blade - To cut off excessive strip protruding out
- First you extract the nail from the tyre using the pliers
- Then you insert the smoothening tool & insert & extract it a few
times to make sure the puncture the big enough to accommodate the
repair strip & is also smooth enough.
- Then leave the tool half-inserted.
- Now, take one Puncture Repair Strip & inert it into the Puncture Strip Insertion Tool. It's like threading a needle!
- It's fine when the strip is halfway through the tool.
- Now take out the Smoothening tool & insert the Insertion Tool.
- Insert the same till only about 10mm of the strip is left above the tyre.
- The inserting tool will not go all the way in. It will stop after the
plastic bit of the handle touches the tyre after which it can be pulled
out. At this point, the seal strip will be left inside the tyre blocking
the hole in the tyre.
- You can now trim if you think the strip is protruding out too much
It is often possible to repair a damaged tire casing in order to ride
out on a given day. This solution is only good for an emergency repair,
so replace the tire before your next ride. Here's how to do it: Use a
dollar bill or some other fibrous material to cover the fracture in the
casing on the inside surface of the tire. There is a limit to the size
of the hole you can repair this way. Applying some adhesive on the
material you're using to cover the fracture can help hold the
reinforcing material over larger holes. You will need to install a tube
in the tire after you repair this type of leak unless you are using a
fibrous material that is not permeable to air and is sealed to the
casing well. You should not inflate the tire more than necessary to
finish the ride.
If All Else Fails
You can always use a tube in a tubeless tire to eliminate the issue
of a leak and be able to ride home. You will have to remove the
inflation valve to install the tube, and you can also exchange the rim
strip for a lighter one to save a little weight.
Source : www.bontrager.com
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