Bike Maintenance 3: Puncture Repairs.

04/11/2012   |   Posted by jeremy

 

Today I am going to talk to you about puncture repairs. This may seem like a bit of a mystery to some of you but believe me there is nothing to it.

There are basically two ways that you can deal with a puncture. The first and most difficult way is to find the hole in the tube and patch it with one of those little round rubber patches. The second and easy way which I highly recommend is, when you have taken out the old punctured tube is to throw it in the bin and put a new one in, it’s so much easier than faffing about with glue and patches.

Firstly don’t wait until you get a puncture before doing something about it. At some point in your cycling life you are going to get a puncture so the best thing is to get yourself prepared for when it does happen. Get yourself some kit in readiness for the event.

I would say find out what type of tubes you need, i.e. size and valve type then go and buy a big pack of them, they are cheap these days, you can buy packs of five or ten starting at around £10.00 a pack. Next you will need some tyre levers, again you can buy these in multi packs of three or singular if required. Lastly you will need a pump. That’s about it assuming you have some spanners kicking around the garage. If not you will find most wheel nuts use a 15mm spanner to undo them.

Ok so you’ve got a puncture what should you do. First job is to take out the wheel. I will base this on it being a mountain bike. Undo each wheel nut slowly a bit at a time then take out the wheel.

Next you have to get the tyre off and old tube out. Using one tyre lever at a time insert the curvy end inside the rim and under the bead of the tyre. Lever the tyre over the outside of the rim and hook the other end of the lever onto the nearest spoke. Now get another lever and close to the first one repeat the process. After the third lever has been used the tyre should be over the rim enough to get your fingers under it and release it all the way round.

Now pull the tube from inside the tyre, undo the valve retaining nut if it has one and the dust cap on the valve so that you can push it back through the hole in the rim and pull it free from the wheel. I would recommend taking the tyre right off the bike, you shouldn’t need any more levers to pull the tyre off the rim as you will have plenty to grab hold of.

You will of course need to determine how the puncture occurred so first I would check the rim. Look at where the spokes go through the rim, there should be some tape covering the ends of the spokes to protect the tube from being speared by them. Make sure that it is in place and central on the rim. Generally check all round the rim too for sharp pieces of metal etc.

Next you need to check the tyre. Firstly do a quick visual check on the outside of the tyre for anything obvious such as thorns, glass, bits of sharp stone or nails. If you see something suspicious just look inside to see if they go all the way through, you may have to bend the tyre with your hands a bit to see. If it does go through pull it out from the outside and double check to see that you have got it all out. A pair of long nose pliers is handy for this and something with a point on it in case you need to dig an object out of the tyre.

Top Tip. Don’t assume that just because you’ve found something it means it will be ok to put it back on the rim. There may well have been multiple objects penetrating the tyre so go round and check the entire tyre. I would also if possible turn the tyre inside out so you can really see and feel with your fingertips, what’s going on.

When you are satisfied the tyre is ready to go back on, check to see which way round it should go on. Some tyres have a direction arrow that point the way they roll round when going forward. Otherwise look at the tyre pattern, if it looks a bit like an arrow head put the point of the arrow facing the front. Sometimes the back one can face backwards for grip even if the arrowhead or maker is telling you otherwise, but for most bikes I would go with the arrow.

Before you start to mount your tyre back on the rim, get out a new tube and put a bit of air in it. Leave it for five minutes to make sure it holds air as sometimes they are not perfect when they are new. While you wait, mount one side of the tyre onto the rim, this should be quite straight forward and will not require any levers. Next with some air still in the tube, not too much though, feed the valve through the hole in the rim and push the tube into place inside the tyre. The air will make sure the tube stays round and will also help preventing any pinch punctures when getting the other side of the tyre in place.

Make sure the valve sits square to the rim, if it doesn’t pull the whole tyre one way or the other and you will see the valve move with it. Now it’s time to get the other side of the tyre on. In a lot of cases you will not need any levers to do this if you are lucky. Start by sitting with the tyre and wheel upright on your lap and use both hands to grab the tyre as if holding a car steering wheel but with your hands quite close together. Now use your thumbs to push the tyre over the wheel rim and into place. Work your way round the tyre. It will get more difficult as you get to the end as the tyre bead becomes tight across the rim of the wheel.

 You now have two options, you could put a bit of washing up liquid onto the bead of the tyre to help it slip over the rim and into place or you could use a lever. If you are using levers be very careful at this point not to squash the new tube against the rim or the lever and making a hole in the tube. Use the levers very close together so that it is easier.

Purists will say never use levers to put a tyre back but I say use them carefully if needed and everything will be fine. Some tyres will pop straight onto a rim quite easily without any liquid or levers and that is great when they do.

Once the tyre is on you have to make sure that the tube isn’t caught up anywhere. Put a bit more air in and then with the wheel on your lap again go round the tyre squeezing it together so that the tyre bead goes into the centre of the rim and out again when released. If you can’t squeeze it there is too much air in there so let some out and try again.

Keep looking as you go to see the new tube is sitting inside the tyre and fitting well. When you are happy, place the wheel back in the frame and with the weight of the bike on the wheel do the nuts up making sure that the wheel is central in the frame.

Pump up the tyre fully and importantly, make sure the brakes are connected properly, lift the bike and give the wheel a spin to make sure it’s all ok. Job done, no hassle with glue and patches etc.

Top Tip. Why not keep a few tools on your bike in a seat pouch and a spare tube in case you get a puncture while you are out and about. Or at worst make sure you have your phone with you to call for help. Don’t forget to keep an eye out for our next maintenance blog next week and also any blogs that will be coming up using the RSS feed on the website.

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