Bicycle repeated punctures.

[Maybole]

I cannot find a dedicated cycling forum, if there is one, mods please move to it.

 

I am getting repeated slow leaks developing in the same place every approx 60 km. It is always along the seam which runs round the inside of the tube, ie, that part which is in line with the valve and in contact with the rim away from the tyre. Therefore, it cannot be a penetration from outside. It is always just a few cm. from the valve. If I repair it, the puncture recurs in a similar place about one cm. further along the seam. After 3 punctures I replace the tube and it happens again. I have replaced 2 tubes so far.

I cannot find any flaw in the rim tape but I have reinforced it by wrapping plastic electrical tape round the rim on top of the rim tape. The tube still punctures.

This is totally outside my experience, can any cycling fanatic suggest a cause and a cure. Additionally the tubes have all been from different manufacturers so it is unlikely to be a bad batch of tubes.

 

 

 

[Crossy]

I would immediately be looking at a sharp/protruding spoke end since it's always the same place.

 

Moving to the (well hidden) Cycling Forum ???? 

 

 

[Maybole]

4 minutes ago, Crossy said:

I would immediately be looking at a sharp/protruding spoke end since it's always the same place.

 

Moving to the (well hidden) Cycling Forum ???? 

 

 

I have already tried that and cannot find nor feel anything. By the way. where is the cycling forum?

[Crossy]

Just now, Maybole said:

I have already tried that and cannot find nor feel anything. By the way. where is the cycling forum?

 

Yeah, I thought you would have already checked, but ...

 

Cycling lives down:- Thailand Extra Forums => Community Forums => Sports, Hobbies and Activities => Cycling in Thailand (did I say it was well hidden?).

 

[AndyAndyAndy]

Isn't you inner tube slipping inside a tire? Because valve is fixed to the rim. And if the inner tube is slipping/twisting/moving around, it will ripe itself at the valve. It could be due to improper inner tube size or due to some general slippery condition inside tire.

[blackshadow]

run a finger on the inside of the tyre......there could be a small sliver of glass or other sharpe projectile sticking through outside to inside of the tyre...

I had same problem yrs ago.....I did what i suggest and it was a the end of a thorn sticking into the inside of tyre !!!!!!!!!!!!

[carlyai]

31 minutes ago, Crossy said:

I would immediately be looking at a sharp/protruding spoke end since it's always the same place.

 

Moving to the (well hidden) Cycling Forum ???? 

 

 

Great. Thanks for the bicycle forum pointer. ????

[StreetCowboy]

How old are the tubes?  
 

I think I might start throwing away my spare tube and replacing it, if I have not used it in a year.

[473geo]

Check a spoke is not flexing when you ride, that is check the tension of the spokes around the problem area 

For a fix, cut a few inches of old inner tube, make a hole so the valve helps hold it in place and it covers the offending area on the rim, after a while or if the problem reoccurs, check for any sign of friction wear on the rim 'patch' you have fitted 

[Maybole]

To clarify, I have already examined the in situ rim tape for any penetration by spokes. The punctures are occurring on the inside of the tube away from the tyre ie. that part if the tube in contact with the rim trough.  I have also added another layer of tape to the rim The tubes are of the size recommended on the tyre and newly bought from the shop. Also the leaks are exactly on the seam as if the seam itself has parted., but because it has affected 3 tubes of different makes it cannot be a manufacturing fault in the tube.

[Maybole]

11 minutes ago, 473geo said:

Check a spoke is not flexing when you ride, that is check the tension of the spokes around the problem area 

For a fix, cut a few inches of old inner tube, make a hole so the valve helps hold it in place and it covers the offending area on the rim, after a while or if the problem reoccurs, check for any sign of friction wear on the rim 'patch' you have fitted 

That is a good idea thank you.

[CharlieH]

Change to tubeless tyres.????

[Kwasaki]

If you can't fix it yourself there's professional bicycle shops about where there are people that could help. 

[scubascuba3]

3 hours ago, Maybole said:

I have already tried that and cannot find nor feel anything. By the way. where is the cycling forum?

It's the few mm metal like a staple in the tyre, you can't feel it unless you take the tyre off and turn inside out and look and feel very carefully. Should be easy for you as the puncture is in the same place.

 

Quite common 

[StreetCowboy]

8 hours ago, Maybole said:

To clarify, I have already examined the in situ rim tape for any penetration by spokes. The punctures are occurring on the inside of the tube away from the tyre ie. that part if the tube in contact with the rim trough.  I have also added another layer of tape to the rim The tubes are of the size recommended on the tyre and newly bought from the shop. Also the leaks are exactly on the seam as if the seam itself has parted., but because it has affected 3 tubes of different makes it cannot be a manufacturing fault in the tube.

I take it by "newly bought" you mean recently bought, not new but stored in the cupboard for years.
I have had unused but old tubes fail on the fold where they are pressed for wrapping.  I have also had tyres fail on the seam, both of which I found difficult to patch effectively.

Have you checked the manufacturing date of the tubes?  Maybe they have aged in the shop before you bought them, rather than after you bought them.  Were they all bought from the same shop, despite different brands?

 

As CharlieH says - try tubeless.  Although I am not ready to do so myself.  I believe that there is a different set of skills for dealing with them, and since I lack the skills for inner tubes, I don't fancy my chances on something new and innovative. 

[huangnon]

22 hours ago, AndyAndyAndy said:

Isn't you inner tube slipping inside a tire? Because valve is fixed to the rim. And if the inner tube is slipping/twisting/moving around, it will ripe itself at the valve. It could be due to improper inner tube size or due to some general slippery condition inside tire.

Yep, that happened a lot with my mountain bike and my son's BMX also. Have to make sure you inflate the inner right up to the manufacturer's recommendation, if any softer it will slide inside the tyre causing erosion and damage, especially near the valve.

[Maybole]

4 hours ago, huangnon said:

Yep, that happened a lot with my mountain bike and my son's BMX also. Have to make sure you inflate the inner right up to the manufacturer's recommendation, if any softer it will slide inside the tyre causing erosion and damage, especially near the valve.

The valve is not tearing out. I am aware of the dangers of under inflation. I normally, inflate to 80 psi this being the lower limit of the recommended range. The max recommended is 100psi, I will try inflating to the max to see if it helps

[frequentatore]

MTB tire

Flat 3 days in a row. I checked for cuts on the tire, then inside --> found a 2mm piece of glass stuck in the rubber (couldn't feel it with my fingers).

[NanLaew]

On 7/18/2022 at 2:26 PM, scubascuba3 said:

It's the few mm metal like a staple in the tyre, you can't feel it unless you take the tyre off and turn inside out and look and feel very carefully. Should be easy for you as the puncture is in the same place.

 

Quite common 

The OP is getting repeated punctures on the rim side of the tube, not the tire side. Before he clarified that, I was going to suggest a broken wire strand on the inner tire wall. I had that waste a couple of tubes for me.. I had to take the tire off completely and flex it hard, pushing the treads up while pulling the rims apart. That revealed a tiny metal spike that was totally hidden when there was no air on the tube and no weight on the tire.

 

The OP is getting repeat punctures in the same place. Has he dismounted the wheel from the bike and removed the tire and tube completely and very closely inspected the rim only? Don't look for obvious big things like errant spokes but tiny things like an imperfection on the rim or a tiny bit of swarf. It could be something that's almost imperceptible to the touch but keeps pressing or rubbing on the same bit of tube every wheel rotation, causing friction and heat.

[StreetCowboy]

4 hours ago, NanLaew said:

The OP is getting repeated punctures on the rim side of the tube, not the tire side. Before he clarified that, I was going to suggest a broken wire strand on the inner tire wall. I had that waste a couple of tubes for me.. I had to take the tire off completely and flex it hard, pushing the treads up while pulling the rims apart. That revealed a tiny metal spike that was totally hidden when there was no air on the tube and no weight on the tire.

 

The OP is getting repeat punctures in the same place. Has he dismounted the wheel from the bike and removed the tire and tube completely and very closely inspected the rim only? Don't look for obvious big things like errant spokes but tiny things like an imperfection on the rim or a tiny bit of swarf. It could be something that's almost imperceptible to the touch but keeps pressing or rubbing on the same bit of tube every wheel rotation, causing friction and heat.

It might be worth replacing the rim tape, and before that, checking the tension of all the spokes, brush the rim carefully with a brush, and while you’re about it, make three 360 degree turns to starboard in front of the Tin Hau temple, to avoid capsize.  
We did not get to where we are today by blindly relying on common sense and our own meagre understanding of the world around us.

You might also want to sprinkle talc inside the tyre whenever you replace the tube. It might do less harm than good, it might help you feel that you are doing your best, and it come in handy as an explanation if your wife queries the talc. 

Edited July 19, 2022 by StreetCowboy
Excursion to the far side

[MrNatural]

I read all the suggestions till the end and they don't seem very helpful. I will try mine : change the set wheel/tire/tube

[Sticky Rice Balls]

On 7/18/2022 at 11:06 AM, Maybole said:

By the way. where is the cycling forum?

coming around the bend now....... ????

[StreetCowboy]

Since the OP has not posted since July, I think we can assume that either the problem has gone away, or the bike has gone in the bin.  If the former, then a close-out comment from the OP may be helpful for others suffering similar problems, @Maybole

[Maybole]

I replaced the tyre outer and left the third tube (repaired ) in. There has been no  recurrence of the fault, although I did get a bougainvillea thorn puncture later. I still cannot work out why th

[Maybole]

the fault happened.

[StreetCowboy]

58 minutes ago, Maybole said:

the fault happened.

The solution is probably more important than the root cause....
D'ye think it was the three rotations to starboard at the Tin Hau Temple to avoid capsize that finally solved the problem?

 

I've bought new self-adhesive patches since my last puncture and failed repair, though I don't trust them.  I also bought new tyre levers, forgot that I had done so, and bought more.  I'll need a bigger top-tube bag for all this stuff...

 

[StreetCowboy]

My replacement front wheel (purchased in 2016 to replace a twisted rim on my road bike following a mishap) is an acknowledged barsteward of the first order for replacing tubes and tyres. So I relegated that wheel to my mountain bike, which was rarely used by my dearly beloved (the frame is too small for me, but That didn’t stop me putting in several thousand km back in the day) and occasionally by my buddy’s sister, when she visits.

After the last loan, the tyre went flat; my buddy fixed it - and again, before returning the bike in good

Nick; and the tyre deflated.  My buddy took this as an affront to his manhood, and asked that I let him resolve the problem.  Some weeks later, he says I can collect the wheel, but if it suffers a puncture in the future, scrap the wheel and keep the tyre.  Schwalbe Marathons rarely suffer punctures on the road, but they’re not easy to fit - especially on that wheel.