Inner tubes with 'extra' punctures

[foxyrider]

Having fitted my last new tube at the weekend, with it being wet this morning i thought i should do a bit of tube patching.

To be clear, i hate doing puncture repairs, i usually use a tube for one puncture then pass it on to someone with more patience, over the last 2 years or so i've accumulated @ 2 dozen such tubes. But times are hard, no one is doing offers on tubes, even Halfords own brand are a fiver each so time to do some patching.

I selected half a dozen tubes of the size and valve length to fit my 'daily' ride and set to work. Holes were found, patches affixed then inflated to check. Of the six, three went straight down, okay, one was because i'd somehow stuck the patch next to the hole instead of over it but the other two both had a second puncture elsewhere on the tube (not snake bites). How is that possible? The tubes were changed out when they deflated with a puncture so where/how did the second hole come from? Never had this issue when using tubes to one puncture!

Discuss.

[philvantwo]

24 punctures in 2 years?
Sounds like you need to invest in some decent tyres!

[Paulatic]

First thing to note is you’ve had a puncture a month over the last two years! That’s extremely high IME.
Two holes in same tube you got the second before you were aware you had the first.

[TheBomber]

What sort of pressures are you using? I used to find it a problem with the lower pressures used in mountain biking - as the thing that caused one of the punctures also plugged the hole until tyre and tube were separated. So when checking a tyre to find the cause of a puncture, don’t stop when you find it as there may be more.

[ANTONISH]

24 punctures in 2 years?
Sounds like you need to invest in some decent tyres!

+1 (says he who once had five punctures during a 400k audax).
Better tyres is the way forward.
I usually only get about one puncture a year since improving mine.

[mig]

what happens to the tube in the time between the visit and then you getting around to patching it?

is it rolled up somewhere maybe in a drawer? any part of the tube packed tightly against an open valve maybe?

[mjr]

First thing to note is you’ve had a puncture a month over the last two years! That’s extremely high IME.

Not excessively so if riding daily over suburban crap. A lot more people in cars seem to be throwing bottles at kerbs since lockdown and street sweeping hasn't increased to match. Filthy swines.

I think some in-and-out-again pinpricks, not bad enough to cause punctures while inflated inside a tyre, open enough to puncture when the tube is tested outside.

[foxyrider]

First thing to note is you’ve had a puncture a month over the last two years! That’s extremely high IME.

High? considering that i've ridden something like 22,000 miles in that period and worn out something like a dozen tyres in the same period i don't think its too bad. One a month might be the average but i've had up to 6 months in that period Fairy free only to get several thorn incidents in a week (there are lots of thorns around here!).

As for tyre quality, the £10 Kenda's i'm currently using have had far fewer punctures than the £30 Gatorskins i had on previously. The tyres (25c & 28c depending on bike) are usually run between 80 and 90psi but may drop to 70psi on occasion, the punctures don't occur in greater numbers at any particular pressure. Riding is @ 90% tarmac, 10% byways/bridleways.

Used tubes are stored in a loose condition, nothing sharp nearby and with caps on the valves.

[Barrowman]

Are you re inflating your tubes inside a tyre? Might be a Granny suck egg moment here, is the thing that caused the puncture still embedded in the tyre carcass? That would explain a second hole in a repaired tube.
And if you aren't inflating inside a tyre, is the tube getting bigger than it was inside the carcass and stretching a small nick into a hole ( unlikely but not impossible)
I used to be the club puncture champion. 5 in a day ( old tyres) . And most bizzare : carrying trike upside down over a footbridge , caught a wheel in a hawthorn tree . To the general amusement of the rest of the group.
At the time of the 5 hander, I invested in 'punture proof tubes ' (Specialised I think) lot thicker on the tread side of the tube but the valves pulled out.

[531colin]

First question; whereabouts on the tubes were the 2 "extra" punctures? Tread or sidewall position?

Its readily possible to get 2 penetrating thorns in a tyre at any one time....but if you leave one of the thorns in the tyre it will become obvious because the new tube deflates.
It is possible, I guess, you have had 2 incidences each involving 2 thorns, and you have either removed both thorns from the tyre, or one has been an "in and out" event.

I have once ridden with somebody who fitted undersized tyres to wide rims, and we rode some stony tracks on the North Yorks moors; he got several impact punctures which were "twicers" ; the only explanation we came up with was that the second puncture occurred as the tyre was deflating from the first puncture. The holes were "sidewall" position, and didn't always have the typical 2 nips.