Punctures

Your bike is a high tech machine but unfortunately punctures are still part of the cyclists life. They always happen at the worst time and you can go months without one and then get three in one week! Your easiest course of action is to carry a spare inner tube, tyre levers and a pump, so that you can be back on the road in minutes. It’s always worth keeping the old punctured inner tube when you get back home and use it as a spare.

Tools:

• Pump

• Tyre Levers

• Spare Inner Tube or Puncture Repair Kit

• Small Needle Nose Pliers (not essential)

• Spanner (usualy 15mm but could be 17mm or 19mm for BMX bikes)

Diagnosis If you suspect a puncture it can often be worth inspecting the tyre to give you an idea whether your tyre is obviously punctured. Give the type a good squeeze and look over to see if you can spot any thorns of other matter penetrating it.

Try pumping the tyre to see if it will hold air. Tyres will naturally lose air over time so if your bike has been left dormant for a while it is quite likely that the tyres are low on air and just need topping up. If you’ve exhausted these options and all of the signs are pointing towards a puncture, then you will need to remove the wheel from the bike.

Releasing the Brake In order to remove the wheel from the bike, you will need to release the brake to allow the tyre to pass between the brake pads. Firstly you will need to remove the ‘noodle’ (metal tube at the top of the brake) from its cage which is attached to the left side of the brake. Pull the ‘noodle’ away from the wheel. Then you unhook the ‘noodle’ from the catch and the end of the cage.

Rear wheel removal Firstly put the bike into its highest gear on the rear gears (smallest cog, outmost from the centre of the bike or highest number on the shifter) this will aid you in removal and refitting of the wheel. Once the bike is in top gear you can then begin to remove the wheel from the bike.

To remove the wheel you will need to undo the quick-release lever which is located on the left hand or non-drive side of the bike at the axle in the centre of the wheel.

To undo this lever you need to pull it away from the bike until it is in its ‘open’ position, 180 degrees or opposite from its original ‘closed’ position. This can often be indicated by the words ‘open’ and ‘closed’ which are usually printed onto the quick release lever.

Some bikes are equipped with ‘bolt-up’ wheels. These wheels are removed and refitted the same as quick release’ wheel except that you undo/tighten the bolts with a spanner (usualy a 15mm spanner although it may be a 17mm or 19mm for BMX bikes).

Once the lever is undone the wheel will become loose in the bike, once this is achieved it will be easily removed from the bike by lifting the frame of the bike up and away whilst simultaneously pulling the wheel downwards and back away from the bike.

You may need to untangle the chain from the wheel but this can be easily done by pulling back the derailleur/gear changer and allowing the cogs to clear the chain.

To remove the wheel from the front of the bike you perform the same actions as with the rear wheel bar the gears, except once you’ve undone the quick release lever you will need to undo the nut on the opposite side of the quick release. This only need to be undone two or three turns and not removed fully.

 

Removing the Tyre Firstly ensure that any remaining air has been removed from the tyre. Depress the centre or core of the valve until the air stops coming out. With you thumbs push the tyre in towards the centre if the rim, then, using the lipped end of your tyre lever, lever the tyre off the rim.

You will then need to run the lever around the rim removing one side of the tyre from the rim. Then, using the tyre lever from the other side of the wheel, force the remainder of the tyre off the rim in the same direction as the rest of the tyre. You will then need to remove the inner tube from the tyre.

Once the tube has been removed, check the inside of the tyre for any thorns or glass that is penetrating the tyre. If any such offending items are found they must be removed using your fingers or a pair of pliers. Also check the rim for any metal burrs or sharp edges that could puncture the tube, also check the state of the ‘rim tape’ which is used to cover the ends of the spokes. If this is in poor condition it must be replaced or the new tube will become more prone to punctures.

Fitting the Tube You are now ready to fit the new tube. Remove it from its box, unfold it and remove the valve cap. Attach your pump and inflate the tube just enough to give it some shape then feed it into the tyre.Once the tube is fitted, locate the valve on the tube and the valve-hole on the rim of the wheel and push one into the other. Then begin to push the tyre back over the rim whilst working around one side of the wheel until that side of the tyre is seated

When the tyre and tube have been fitted the tyre is ready to be pumped. Look on the wall of the tyre to see what the recommended pressure range is. It can be anything between 30psi – 65psi for Mountain bikes or 80psi – 150psi for Road bikes. Attach the pump to the valve as before and begin pumping. If you have a pump with a pressure gauge you can watch the pressure in the tyre begin to increase. If you don’t have a gauge keep pumping until the tyre is firm to the touch.

 Refitting the Wheel The next stage is to refit the wheel to the bike. This is the reverse of the removal process including joining up the brake.

Once the wheel is fitted it can be worth pedalling the bike and running through the gears to ensure that everything is working correctly. Also squeeze the brake to make sure that is in proper working order.