Constant punctures, advice please.

snollup

Over the last six weeks or so I've been getting about one puncture a week. I had fairly old Gatorskins on the bike but about three weeks ago replaced them with a lovely set of new Conti GP4000s but still puncturing. I have checked that no spokes are coming through the rim tape and have inspected the inside of the tyre making sure that there is nothing inside that shouldn't be there. My commute is short, Drumcondra to Pembroke St. This is driving me insane! Can anyone give me some advice/tips on how I could remedy this?

butterworth

Are you sure you're using the correct size tubes? Unlikely, but it's work a look. Additionally you could also check the outside of the tire for bits of glass wedged into the rubber. Sometimes you have to squeeze what look like tiny holes and fish out the glass with a precision screwdriver or something similar. Over time they could work their way through and cause punctures.

NorthernRaider

snollup wrote: »

Over the last six weeks or so I've been getting about one puncture a week. I had fairly old Gatorskins on the bike but about three weeks ago replaced them with a lovely set of new Conti GP4000s but still puncturing. I have checked that no spokes are coming through the rim tape and have inspected the inside of the tyre making sure that there is nothing inside that shouldn't be there. My commute is short, Drumcondra to Pembroke St. This is driving me insane! Can anyone give me some advice/tips on how I could remedy this?

Do you make sure that when fitting the tube is not overlapping itself (this can cause friction, then punctures)?

Beasty

Swap tyres between the wheels to establish whether it's the tyre or wheel that's the issue - if the punctures stop you're sorted ...

snollup

butterworth wrote: »

Are you sure you're using the correct size tubes? Unlikely, but it's work a look. Additionally you could also check the outside of the tire for bits of glass wedged into the rubber. Sometimes you have to squeeze what look like tiny holes and fish out the glass with a precision screwdriver or something similar. Over time they could work their way through and cause punctures.

Fairly sure tyres are the correct size but will double check. If not could this cause a problem?

Have checked tyre both inside & out. as far as I can see all is ok. Punctures seem to always be on rear wheel so plan on swapping tyres over to try to eliminate a faulty tyre.

I was also considering buying some kevlar tape to line tyres. Does anyone have any experience using it? Does it help?

Cee-Jay-Cee

Each time you get a puncture are you able to find the offending glass or whatever it was that caused the puncture? What tubes are you using?

snollup

CJC999 wrote: »

Each time you get a puncture are you able to find the offending glass or whatever it was that caused the puncture? What tubes are you using?

Yes, have always found the cause. Have no idea of the tubes I'm using.

Plan on swapping tyres over to try to eliminate dodgy tyre as the cause.

07Lapierre

Are you inflating your tyres to the correct pressure?

willabur

sounds as tho he could be pinching the tube

snollup

07Lapierre wrote: »

Are you inflating your tyres to the correct pressure?

I think so. Was inflating to 120PSI originally but have since changed to 100PSI.

snollup

willabur wrote: »

sounds as tho he could be pinching the tube

No, definitely not. I'm super careful to check that the tube is not caught under the tyre before inflating.

07Lapierre

If your not pinching the tube, inflating the tyres incorrectly and the tyres, tubes and wheels are OK, then the only thing you can do is buy a new bike!

snollup

07Lapierre wrote: »

If your not pinching the tube, inflating the tyres incorrectly and the tyres, tubes and wheels are OK, then the only thing you can do is buy a new bike!

You my friend are a genius!

rollingscone

And are you sure the tube is perforated every time?

Check that the valve core on your presta tubes isn't loosening under pressure (Can be fixed with two sets of pliers/grips and a bit of gentle handling).

Outkast_IRE

After a regular series of punctures I got some panaracer flataway Tyre liner.
http://www.wiggle.co.uk/panaracer-flataway-tyre-liner/

No punctures in 18 months now since I put it in. And I have cycled over some bad patches of glass etc. Its great stuff in my opinion.

godtabh

Is your rim tape ok? I had major issues with rim tape on my first bike leading to lots and lots of punctures. Replaced the rim tape and I was flyin g

clank :o)

I had the same trouble when I got my road bike constant flats were driving me bananas...
Bought a good bike but the inside lip of the (shimano R500) wheel rims were poorly finished / had a sharp edge and I think that was causing problems when refitting the (continental sport) tyre to the rim.

A set of Slime self sealing 700c inner tubes helped a lot too - couldn't find them in Dublin so got from ebay - I was going to get better tyres but the tubes worked well for me so no need in the end. So I reckon the slime tubes are worth a go...

http://www.ebay.ie/sch/i.html?_trksid=p2050601.m570.l1313&_nkw=slime+700c&_sacat=0&_from=R40

browsing

Just because the tube is seated correctly, doesn't mean that you can't get pinch flats. Are the holes two slits exactly beside each other? If you've lowered the pressure, sometimes when you hit a particularly bad pothole the rim can bottom out on the tyre and pinch the tube giving these distinctive holes (described by somebody here as a snake bite.) I'd personally inflate to 115psi or 120psi which is max recommended.

Alek

Drumcondra and Dorset St. is where I get 100% of my punctures recently, including today. Its jinxed if you ask me, nothing to do with your tyres or tubes.

A new bike is NEVER a bad idea, though.

Jabel

Alek wrote: »

Drumcondra and Dorset St. is where I get 100% of my punctures recently, including today. Its jinxed if you ask me, nothing to do with your tyres or tubes.

A new bike is NEVER a bad idea, though.

Travel here every day and since I got my new bike, I haven't had a puncture.
You need a new bike...
QED

check_six

I thought I was getting a slow puncture on my back wheel, it was losing pressure after every journey. Turns out I was not tightening the valve nut enough(Presta valves), and when I put the valve cap on it was pressing on the valve *ever* so slightly and therby letting out the air.

Don't tighten the valve nut too much either, you'll do damage. Just enough so that the valve rod thing isn't flapping about and getting pushed by the cap.

Alternatively, I could have ditched the valve caps...

DaveR1000

check_six wrote: »

Don't tighten the valve nut too much either.........

don't tighten it all - leave it off - devils invention :mad:

sonandheir

I found I was getting a lot of flats on my commute a while back:

1st check your tube is the right size for your tire. if it's too small I found it would hug the rim and the tire will be loose around edges and debris will get inside the tire without puncturing it.

2nd Before each ride I check the tires for small embedded shards of glass. I find at least one small piece each morning. Since doing this I get very few flats, been 2 months since I got a puncture(100 mile commute per week).

Using gatorskins as well for my commute.

Also use max tire pressure 120psi.

rubadub

snollup wrote: »

I was also considering buying some kevlar tape to line tyres. Does anyone have any experience using it? Does it help?

I had liners which had no adhesive. They caused a few punctures themselves by nipping the tube or wearing it down slightly. I had gatorskins and still got punctures, was plagued by them for ages. The liners do better on wide tyres.

I finally got these schwable marathon plus from amazon, email tells me since feb 2012 and not a single puncture since then, 9 miles a day commute.

http://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias%3Daps&field-keywords=marathon%20plus

Now I know most in this forum would probably not like them, too wide & heavy, and threads. For me they are perfect, only negative was they were really hard to put on, but hopefully never have to come off again until they are worn out. I think other ones are more like normal road bike tyres, but I think the "plus" version offered most protection, which is what I was after. I couldn't care less if it added 5mins to my commute, better than turning up 30mins late every fortnight due to punctures -which I also hate fixing.

Dotsie~tmp

"Yes I have always found the cause"

What does this mean? If you find the cause you have your answer. If you mean you find the holes in the tyres this is not the cause but the result. You should always be able to find the penetrating body. If you cant you are getting pinch flats from undrr inflated tyres or spokes/bad rim tape flats on the inside of the rim.

If you cant find the shard and its almost always on the rear im gonna call under inflation or extreme fatbodyitis. Fatbodyitis is easily countered by inflating to 120-130psi each ride (trust me i started riding at 20 stone).

Personally i recommend Bontrages racelite hardcase tyres. Very tough, quite light.

ftgu06

here's advice from a person with over 20 years in the bicycle trade
hopefully you will not get any more punctures but if you do here's the check list for you
1 once you have removed flat tube inflate as much as you can and check is your puncture on top or bottom of tube , bottom being where valve is
2 if on top you have something in tyre , the easiest way to check this is to mark the punctured area on tube with a piece of chalk or pen and then re insert your valve in tyre and bring tube around to the area you marked this will tell you where the problem area is ,
3 once you have done steps 1 and 2 you will now know what your problem is
so in brief if if puncture is on top you have something in tyre and if puncture is on bottom you most likely have a rim tape problem , just add another rim tape or rap insultating tape around your rim a couple of times not for getting to make a hole where your valve goes through

snollup

ftgu06 wrote: »

here's advice from a person with over 20 years in the bicycle trade
hopefully you will not get any more punctures but if you do here's the check list for you
1 once you have removed flat tube inflate as much as you can and check is your puncture on top or bottom of tube , bottom being where valve is
2 if on top you have something in tyre , the easiest way to check this is to mark the punctured area on tube with a piece of chalk or pen and then re insert your valve in tyre and bring tube around to the area you marked this will tell you where the problem area is ,
3 once you have done steps 1 and 2 you will now know what your problem is
so in brief if if puncture is on top you have something in tyre and if puncture is on bottom you most likely have a rim tape problem , just add another rim tape or rap insultating tape around your rim a couple of times not for getting to make a hole where your valve goes through

Thanks for that. Really great tips I never heard before. You can't beat experience!

New tube in and swapped tyres over so will see how we go. If problem persists will be using the above tips. Thanks all.

chinwag

I used to cycle across town regularly. I eventually switched over to kevlar tyres and found that I rarely got punctures after I started using them - punctures became a very rare occurrence. I still cycle locally and still use the kevlar tyres, wouldn't be without them.
PS. Some very useful and helpful tips here though.

snollup

So upon closer inspection I noticed a number of small splits on the outer of both tyres. Must say I am somewhat pi**ed off as the tyres are only a few weeks old. I would have expected more from Conti GP4000s.

Alek

splits? do you mean cuts?

Wishbone Ash

clank ) wrote: »

.....A set of Slime self sealing 700c inner tubes helped a lot too - couldn't find them in Dublin so got from ebay...

Eurocycles and Halfords stock them.

rubadub wrote: »

...I finally got these schwable marathon plus from amazon, email tells me since feb 2012 and not a single puncture since then, 9 miles a day commute.

http://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias%3Daps&field-keywords=marathon%20plus

Now I know most in this forum would probably not like them, too wide & heavy, and threads. For me they are perfect, only negative was they were really hard to put on, but hopefully never have to come off again...

I usually put them on my beater for the winter. If you think Marathon Pluses are hard to put on/take off, you should try getting Panaracer Ribmos off and on at the side of the road. Marathons are child's play in comparison!

Alek wrote: »

Drumcondra and Dorset St. is where I get 100% of my punctures recently...

I've never punctured there and I cover that route several times weekly. Kinsealy/Balgriffin seems to be where I'm jinxed.

snollup

Alek wrote: »

splits? do you mean cuts?

Yes, cuts.

Think if I have to change them it will be to Panracer Ribmos.

Alek

They're cuts in the outer rubber layer or all the way through?

I don't really think there is a tyre that would protect you from the former, especially if you are commuting through the inner Dublin glass fields.

Even my Marathons pro have plenty of these cuts. No puncture so far though.

snollup

Alek wrote: »

They're cuts in the outer rubber layer or all the way through?

I don't really think there is a tyre that would protect you from the former, especially if you are commuting through the inner Dublin glass fields.

Even my Marathons pro have plenty of these cuts. No puncture so far though.

Only outer layer. Will see how they go over the next week or two and then decide if they need to be replaced. I'm absolutely reliant on my bike for work so cant keep getting punctures on such a regular basis.

Alek

Marathons + slime tubes will give you confidence and 1 - 1,5kg extra to your bike.

snollup

Alek wrote: »

Marathons + slime tubes will give you confidence and 1 - 1,5kg extra to your bike.

I may try the slime tubes. Do you use the lite or regular ones?

Alek

I don't find them necessary with Marathons but my wife had them on her bike with some regular schwalbes, regular version. After a year I've checked her tyre and it was full of glass embedded in the rubber - no complete punctures though! Just one slow leak as far as I remember, that fixed itself.

snollup

Alek wrote: »

I don't find them necessary with Marathons but my wife had them on her bike with some regular schwalbes, regular version. After a year I've checked her tyre and it was full of glass embedded in the rubber - no complete punctures though! Just one slow leak as far as I remember, that fixed itself.

On that recommendation I will be ordering a pair this evening!

rubadub

snollup wrote: »

On that recommendation I will be ordering a pair this evening!

my marathon plus were cheapest on amazon, since they do free postage over £25, also came in a massive box with minimal bending of the wire bead, some other place folded my tyres right over to fit them into a miserably small box.