Compared to car tyres, motorcycle tyres are expensive. A bike tyre’s shape varies compared to a car tyre, with car tyres being flat and motorcycles having a rounded profile. This is why getting a motorcycle tyre puncture can be so frustrating. Most motorcycles run tubeless tyres, which means the tyre forms a seal with the rim. This means that if you get a puncture on a tubeless tyre, it can normally be fixed with a plug. There are some conditions to this, like the puncture’s location within the carcass and the diameter of the puncture.
How do I fix a motorcycle puncture?
Modern tyres are constructed to be ever more puncture resistant. That said, sod’s law says there will be more sharp objects on the road to test them. This doesn’t help if you already have the puncture. Chances are a small hole can be plugged with a plugging kit, but a plug kit fix should only be regarded as a temporary measure.
The offending can be anything from fixings like bolts, nails or screws, glass fragments or even natural objects like thorns, twigs or stones.
Instant or slow puncture?
There are also two types of puncture, instant or slow. An instant puncture normally happens when an object cuts through and then leaves the scene allowing the air to exit through the hole. Normally a tyre will deflate quickly and sometimes without warning. These will normally leave you at the side of the road stuck or in a mood at home with a flatty.
On the other hand, slow punctures are normally where the object remains inside the tyre carcass and can semi seal the hole. This allows much less air to escape, and sometimes air will only escape under the vehicle’s weight, once per wheel rotation. This means that it can take much longer to reduce the tyre’s level to a noticeable level I,e slowly over a few days.
Normally the offending item will be easy to spot, but if not, mix up some washing up liquid into a spray bottle and spray it on. Any air leaking from the tyre will bubble up, leading you to the area. This is also useful if the air is leaking from the rim due to corrosion.
How can I avoid punctures
Unfortunately, there is no surefire way to avoid a puncture, but there are some ways to try and reduce it. Often there is road debris found in the ‘Unswept areas of the road. These are the edges of the road near the kerbs, as anything that falls into the road gets brushed outwards by traffic. Therefore filtering on a motorcycle can put you in the at-risk areas of picking up a motorcycle tyre puncture. Next time you stop at a traffic light, have a glance at the kerb and see the build-up.
Correct tyre pressures can help reduce punctures
Failing that, running tyres at the correct pressures can reduce punctures as it makes it harder for the protruding object to puncture the carcass.
Also available are sealing compounds inserted into the tyre body through the valve, and then the tyre is inflated. These roll around the inside of the tyre and stay liquid. In the event of a puncture, the internal air pressure forces the liquid outside through the puncture. Upon meeting the outside air of the tyre, the compound will harden and seal the hole up. Manufacturers do not recommend these liquids. People do rate them, and they work if you believe the stories.
British standards does advise against the use of sealants, as do manufacturers.
Can I plug a motorcycle tyre?
British Standard BSAU159F exists to guide motorcycle tyre puncture repairs. It determines the locations where a tyre can or cannot be repaired and the type of repair needed.
Repairs are a very grey area. Manufacturers insist on a safety perspective; a repaired tyre is unsafe. Especially on any high speed rated tyres, these shouldn’t be repaired. If the tyre has been run flat or underinflated for a long time, it is no. Running a tyre flat wears the tyre’s sidewalls, which affects the structural rigidity and makes the tyre unsafe.
Sidewall repairs are not allowed
No repairs are allowed in the sidewall area. The carcass must also be inspected for secondary damage or multiple strikes. For example, if it has pierced the tread and also damaged the sidewall.
The only area allowed to be repaired is 25% each side of the centre line of the tyre. Repairs must be made with a mushroom type plug which vulcanises itself to the tyre sealing the hole.
Normally only one repair is allowed per tyre due to safety. Anything rated above a V rating (130mph+) cannot be repaired and should be replaced.
Is a repaired tyre safe?
Repairs under the guidelines of British Standards should be safe. However, the industry dislikes tyres being repaired and will always recommend a replacement. Sceptics say ‘Of course they will, their business is to sell tyres’. Yes of course it is, but these companies spend huge amounts on R&D and testing and know a thing or two about what they make.
Regardless any repair should only be regarded as a short term fix until it can be replaced.