Keep getting punctures, Help!!!

[HJ]

120 psi is a tad high. This actually may be your problem.

Not if they are racing tires...

 

[Ademort]

It could be any one of a number of things, but firstly what tyres do you have on the bike and what size are they.
Ademort

 

[Randochap]

Not if they are racing tires...

From the OP:

Bought a hybrid a while bk for a 18mile round trip to and from work ...

So what's the chance they're racing tyres?

Even if they were, there's not any benefit to running them at 120, unless someone is looking to get rid of some old tooth fillings..

 

[CycleChris]

Hey everyone sorry for late reply:
They are racing tyres, maxxis detonator which is very apt considering they keep exploding, it says max pressure 120psi on the tyres, and I just pump them up to that, because I dont want the bumps to have an affect puncture wise, the last puncture was a pinch i think but dont know about the others.

 

[HJ]

From the OP:

Bought a hybrid a while bk for a 18mile round trip to and from work ...

So what's the chance they're racing tyres?

You were saying??

 

[ASC1951]

it says max pressure 120psi on the tyres, and I just pump them up to that..... the last puncture was a pinch i think but dont know about the others.

That's weird. A pinch flat is when the tyre is forced out sideways so far that the tube is pushed against the inside of the rim. I don't see how you can have that happening if you really do have 120 psi in there - it only ever happened to me before I got a track pump, when I was running tubes at 75-80 psi.

Sorry to cast nasturtiums, but is your gauge accurate? 120 psi means that you can hardly dent the tyre with the firmest thumb pressure.

I would put my money on sharp rims or thin rim tape. Have the wheel out, check round it as mentioned by others, and if need be run a bit of fine glasspaper particularly round the inner roll of the bead. If the rim tape is thin, a good substitute is electrician's insulating tape, the cloth type.

On factory assembled wheels you sometimes find that their plastic rim tape is plenty thick enough but has been heat-shrunk in the wrong position. You can't re-position those ones, IME, you just have to cut them out and replace with sticky cloth tape.

[I've just though of another possibility. Did you get all your tubes from the same place? I use cheap tubes myself (£2.99 if I can get them) and don't have any problems, but the quality control isn't great on tubes and it is quite possible to get a bad batch. You would still be getting rear wheel blowouts because that takes a greater riding load. Thorn punctures and pinch/snakebites normally affect the front wheel more.]

 

[Randochap]

You were saying??

The Maxis Detonator is no "racing" tyre. And the maximum pressure noted on a tyre does not mean one slavishly follows the maximum recommended. The idea is to inflate for conditions.

I'm writing this from a hotel, as I'm organizing a 600km brevet and just spent the day following riders over a remote, scenic and very hilly piece of west coast topography.

At one control, I helped one of the riders with a flat -- her second with that tyre. Guess what kind? Yep, a Detonator! Who would seriously name a tyre after an explosive device?

As it turned out, the cause was a worn rim tape at the valve hole. An electricians tape patch did the trick. But I noticed the tyre, though new, had plenty of cuts already.

Oh, and I pumped the rear up to 110 and the front around 100.

Well, it's after midnight and it'll be another long day tomorrow. Glad I'm not with the riders who are still on the road ... climbing a mountain pass when we last saw them.

 

[CycleChris]

Thanks again guys will be starting the new improved more knowledgable cycle to work on tuesday thanks to all of you, I think on my pinch puncture i had the wrong size innertube in the tyre, so prob why that happened. I will let you know what has happened later in the week,
Regards Chris

 

[jpatterson]

For people who really really dont want to get more punctures
Its heavy, but at least its good training!

For 'The System' you will need:
1 pair of the biggest puncture proofed tyres that will fit in your frame
an old pair of smaller tyres with the beads cut off
a pair of slime filled inner tubes

Fit the smaller tyres inside the bigger puncture proof tyres and then fit as usual. Fit the slime tubes as usual et voila. Nothing is going to get through those.

Its heavy, its slow, but at least you dont have to worry about flatting.
For the racing folk this is a great setup to run on your winterbike , come easter when the good bike comes out of the shed you will be flying!

 

[Ianesque]

Punctures

I had the same problem. After cycling reguarly for 6 months with only one puncture on a cheap bike, i thought punctures were a relic of my childhood. Then i bought a better bike (better tyres) and lo and behold 6 punctures in 8 weeks!
I did the usual checks of course, checking innertube and usual paths with nothing standing out. Then after another check i found a sliver of sharp metal implanted in the tyre, flush with the inner and outer surface of the tyre but probably poking out with just enough nth of a millimetere on the inside to be causing the punctures. So my advice is to check, check and treble check your tyre!!

 

[bauldbairn]

I had the same problem. So my advice is to check, check and treble check your tyre!!

Good Advice!

....and Welcome to the CC forums Ianesque.

 

[threefingerjoe]

Tip: When checking the tyre for the cause of the puncture, avoid the temptation to run your fingers around the inside of the tyre. On the first check, use your hanky, or a rag. You'll feel it snag on the thorn, nail, glass, or whatever. If it's so small that you don't find it on the first check, only then go back very carefully and look and feel for something.

Once, while repairing a puncture in the dark, I cut my finger on a piece of glass. After that, everything felt sticky...my pump, my headlamp (that I had removed and was using as a torch), the wheels... When I got to work and saw the bike in the light, it looked as if an axe-murder had taken place!

 

[Debian]

I always keep a thin cotton glove on me and wear that to check the inside of the tyre.

 

[Bill Gates]

One thing that no ever mentions is the use of talcum powder. For me this is as vital as the patch or the glue or the pump to putting a tyre on a rim and/or repairing punctures. And I don't mean splashing it on yourself to make you smell nice.

 

[Sheffield_Tiger]

Tip: When checking the tyre for the cause of the puncture, avoid the temptation to run your fingers around the inside of the tyre. On the first check, use your hanky, or a rag. You'll feel it snag on the thorn, nail, glass, or whatever. If it's so small that you don't find it on the first check, only then go back very carefully and look and feel for something.

Once, while repairing a puncture in the dark, I cut my finger on a piece of glass. After that, everything felt sticky...my pump, my headlamp (that I had removed and was using as a torch), the wheels... When I got to work and saw the bike in the light, it looked as if an axe-murder had taken place!

I thought you were going to say "hence the name, three finger joe!!"