Cycling UK Forum

I have now had four punctures in two weeks and only out on the bike six times and all on roads. All four punctures have been on the back wheel and I have taken the bike to the local repair shop for a new inner tube each time, but am now wondering if there could be something wrong with the back wheel to keep getting these puncture.
Its annoying because I had gone nearly four years without ever having a puncture.
Is there anything I should be checking or would you recommend me purchasing a set of puncture resistant tyres I was recommended these
Bontrager gr1 team issue 700x35
My bike is a Trek Duel Sport 1
Thanks for any help

Tonyh wrote:I have now had four punctures in two weeks and only out on the bike six times and all on roads. All four punctures have been on the back wheel and I have taken the bike to the local repair shop for a new inner tube each time, but am now wondering if there could be something wrong with the back wheel to keep getting these puncture.
Its annoying because I had gone nearly four years without ever having a puncture.
Is there anything I should be checking or would you recommend me purchasing a set of puncture resistant tyres I was recommended these
Bontrager gr1 team issue 700x35
My bike is a Trek Duel Sport 1
Thanks for any help

It could be a rim problem, but I have known riders pick up frequent punctures because they ride in the gutter, where debris collects.

Puncture-resistant tyres are always a good idea - there are many out there. Have you checked that the spokes ae well-covered by the rim tape? Nothing lodged in the tyre? Good luck!

Is there a shard stuck in the carcass of the tyre tearing each tube as they get swapped out?

Going to a bike shop for a new tube each time suggests that you aren't fixing them yourself, which possibly means that you aren't familiar with the process of checking for the cause of a puncture?

What caused the punctures? Without knowing this it's difficult to advise.

Did the bike shop say anything? Did they find and remove something from the tyre?

[XAP]Bob wrote:Is there a shard stuck in the carcass of the tyre tearing each tube as they get swapped out?

Going to a bike shop for a new tube each time suggests that you aren't fixing them yourself, which possibly means that you aren't familiar with the process of checking for the cause of a puncture?

That's almost certainly it. The occurrence of punctures is generally random, unless you regularly ride through broken glass or thorns, but a series of punctures IME is a sign of not having traced the cause of the first and dealt with it

It could be something stuck in the tyre (it only needs a very small splinter of glass or similar),

It could be some problem with your rim tape/spoke holes/rim sidewall imperfection.

You won't really know for sure unless you investigate yourself. Are you able to fix punctures?

If yes, then first thing to do is make sure you align the tyre and inner tube in some specific way in order that when you get the next puncture it will facilitate locating the area on the rim/tyre you need to examine. Most people line up some marking (makers brand label say) with the inner tube valve.

If you can't fix a puncture then unfortunately you are at the mercy of the bike shop mechanic and if he is in a rush then he may just put a new tube in after only a cursory examination......thus it will undoubtedly fail again in short order!!

Thanks for your responses and yes I try to avoid getting near the gutters
I did think it could be a rim issue or a spoke on the inside and will check both issues but I also think the puncture resistant tyres might be the best solution, although I don't know anybody who has them fitted but will carry out some research.
No I'm not fixing them myself but maybe I should so I can check all your suggestions myself or I will insist that the shop carry out a full investigation Bit more difficult as I live in Spain and the language barrier can cause some difficulties
Thanks again

No hablo espanol?

Puncture resistant tyres are heavy, resilient & tend to deaden a good bike ride. They should only be fitted to commuter or utility bikes, when a puncture is really, really not desirable (subjective obviously!).

Sod's Law seems to say most punctures happen in the back wheel, especially if you have something like a coaster brake which makes it a bit harder to remove that wheel, but I'd say that a series of punctures in one wheel points to something about that tyre/ wheel rather than bad luck.

It may be the tiniest speck of glass, embedded deep in the tyre where you cannot easily see it and yet it may not protrude through the tyre where you can see it or feel it by running a finger round. It may only come into contact with the tube when it's fully inflated. Modern butyl tubes lack the elasticity of latex and can be punctured by something scratching away. I've posted before that I once only found such a tiny speck of glass by holding up the tyre and seeing the sun sparkling through.

It really does need almost microscopic inspection. As has been mentioned, measuring the distance between the valve and the puncture in the innertube can help locating the cause in the tyre if you fit the tyre with the label near the valve. If you are disorganised like me, then mark the position of the valve with a ballpoint pen on the tyre sidewall before dealing with the puncture.

Squeezing the tyre to open up small cuts can be useful but you really must look right into any cuts. Rainwater seeping into a cut may help you locate damage when inspecting the inside of the tyre, but I'll repeat that the cause may not protrude until the tyre is inflated.

thirdcrank wrote:As has been mentioned, measuring the distance between the valve and the puncture in the innertube can help locating the cause in the tyre if you fit the tyre with the label near the valve. If you are disorganised like me, then mark the position of the valve with a ballpoint pen on the tyre sidewall before dealing with the puncture.

I use the little yellow crayon in the kit to mark the radial position of the puncture (and which way the tyre was on).

Jonathan

Having run a bike shop and subsequent bike repair business I always seek to find the cause of the puncture, otherwise it is pointless replacing or repairing the tube. As suggested above it looks as if the bike shop has just fitted a new tube without finding the cause of the puncture. Even if there is nothing left in the tyre it is almost always possible to find the cause. If for example a thorn has gone in and out of the tyre by locating the point on the tube where the puncture is and examining the tyre at that point you will be able to see where the tyre was punctured. Depending on where in the tube the punctures are occurring it is likely that there is problem with something sharp lodged in the tyre, a defect in the tyre damaging the tube, a badly fitting or damaged rim tape or an overlong spoke. Either way you need to find the cause and it would be very useful to learn how to repair punctures yourself.

Try swapping front and rear tyres to see if you then get a flat on the front, or rear or neither. That will at least give you a clue as to whether it's tyre or wheel related.

Always, always find the cause of the puncture before replacing the tube.

It sounds very likely there is either a sharp trapped in the tyre or something wrong with the rim or tape.

My procedure:


1. Remove one side of the tyre from the rim.
2. Pull the tube out, leaving attached at the valve.
3. Pump up the tube, with the tyre still in place, until the leak is apparent. Sometimes this can require allowing the tube to expand a lot.
4. You now know precisely where the hole in the tube was relative to the tyre, and the rim.
5. Examine the tyre minutely. Thorns, glass, metal wire etc can be surprisingly difficult to find. Remove, ensuring all of the offending object is out.
6. If a culprit cannot be found inb the tyre, remove it and examine the rim where the hole inb the tube was.

And learn how to replace a tube.

Take on on and off a few times at home, and always carry on with you on the road.

It can seem daunting, but a little practice and it's a 10 minute job. Much less hassle and much cheaper than going to the bike shop.