Other kind of strange flats

Another kind of strange flats a friend of mine has got.

The tubes have strings of little holes, millimeters apart but irregularly
spaced, along several centimeters. They appear on both sides/flanks of
the tube, not against the rim, not on the rolling surface.

The tubes are Chen Shin, 700C, for tire width 35 to 43. Tires are 700x38C,
I don't know the brand. Friend says he has replaced tubes with same brand
and has seen the problem reappearing after some time.

We carefully inspected the tire inner surface and found nothing (or I
wouldn't be posting this). Also, in my opinion, there seems to be just too
many of these little holes for them to be caused either by an object
trapped between tire and tube, or by a pinch.

Could it be that the tubes are just [censored] ?

Jacques

Jacques Moser said:

Another kind of strange flats a friend of mine has got.
The tubes have strings of little holes, millimeters apart but
irregularly spaced, along several centimeters. They appear on
both sides/flanks of the tube, not against the rim, not on the
rolling surface.
The tubes are Chen Shin, 700C, for tire width 35 to 43. Tires are
700x38C, I don't know the brand. Friend says he has replaced tubes with
same brand and has seen the problem reappearing after some time.
We carefully inspected the tire inner surface and found nothing (or I
wouldn't be posting this). Also, in my opinion, there seems to be just
too many of these little holes for them to be caused either by an object
trapped between tire and tube, or by a pinch.
Could it be that the tubes are just [censored] ?
Jacques

Tubes could be bad and/or installation method could be flawed, or there
could be something in the rim/tape/tire.

1..Is the tube partially inflated to take donut shape before
installation?

2..Are the tire edges checked around both sides of the rim as the tube
is inflated to make sure that no part of the tube is trapped?

Sometimes a little talc can help the tube slip in where it belongs and
stay nice and donut shaped in it's place securely inside the tire. Can
you get some Michelin or Continental tubes of the proper size and
valve to see if that cares for the problem? Can you pass a cotton ball
around the entire surface area of the inside of the tire without
leaving "snags"?

--

aside from all the usual mechanical failures, cheap tubes can also show
these kinds of faults. impurities in the material or inadequate
vulcanization. just buy a better brand of tube.

Jacques Moser said:

Another kind of strange flats a friend of mine has got.

The tubes have strings of little holes, millimeters apart but irregularly
spaced, along several centimeters. They appear on both sides/flanks of
the tube, not against the rim, not on the rolling surface.

The tubes are Chen Shin, 700C, for tire width 35 to 43. Tires are 700x38C,
I don't know the brand. Friend says he has replaced tubes with same brand
and has seen the problem reappearing after some time.

We carefully inspected the tire inner surface and found nothing (or I
wouldn't be posting this). Also, in my opinion, there seems to be just too
many of these little holes for them to be caused either by an object
trapped between tire and tube, or by a pinch.

Could it be that the tubes are just [censored] ?

Jacques

Jacques Moser said:

The tubes have strings of little holes, millimeters apart but irregularly
spaced, along several centimeters. They appear on both sides/flanks of
the tube, not against the rim, not on the rolling surface.

Sounds almost as if the tire is slipping on the rim, and abrading
the tube as a result. I don't know if it could happen, and if so, if
it would cause that problem, but I suppose that it's a possibility.
--
Rick Onanian

Quoted message said:

Jacques Moser said:

The tubes have strings of little holes, millimeters apart but irregularly
spaced, along several centimeters. They appear on both sides/flanks of
the tube, not against the rim, not on the rolling surface.

Rick Onanian said:

Sounds almost as if the tire is slipping on the rim, and abrading
the tube as a result. I don't know if it could happen, and if so, if
it would cause that problem, but I suppose that it's a possibility.

That's a real possibility on fat tires ridden at 10~20psi
but unlikely (impossible?) at road pressures.
Think 2 pieces of rubber with 100psi pressure. Now slide
them. . .
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971