Tube versus Tire

"buckaroo" <[email hidden]> wrote in :"]news:[email hidden]:

Quoted message said:

My current tires are 700x28C and I use 700x23-26C thorn resistant tubes with no problems. I
am going to 700X32 tires. Can I use my old size tubes or will there be too much
stretch/stress on them.

Tubes stretch alot, but if you stretch them that much, they probably won't be thorn
resistant any more.

Quoted message said:

Tubes stretch alot, but if you stretch them that much, they probably won't be

thorn resistant any more.

Not really that much of a stretch. Going from a 28mm width to a 32 mm should reduce the tube wall
thickness less than 15%, not much in my book.

jon isaacs

Jon Isaacs

(Jon Isaacs) said:

Quoted message said:

Tubes stretch alot, but if you stretch them that much, they probably won't be

thorn resistant any more.

Not really that much of a stretch. Going from a 28mm width to a 32 mm should reduce the tube wall
thickness less than 15%, not much in my book.

I agree with Jon that it will work and that you probably won't have any problems, but would expect
that most tubes won't expand uniformly beyond their designed size. How much difference this will
make is anybody's guess - but I wouldn't be at all surprised if you ended up with some spots in the
tube with significantly less than 85% wall thickness.

Mark Hickey Habanero Cycles habcycles.comhabcycles.comOpen ↗ Home of the $695 ti frame

Thanks for help!

[email hidden] (Jon Isaacs) wrote:

Mark Hickey said:

Quoted message said:

I agree with Jon that it will work and that you probably won't have any problems, but would
expect that most tubes won't expand uniformly beyond their designed size.

My guess is that it takes a lot more than an additional 15% to cause the tube to go non-linear.
The tube is constrained by the tire so it does not have the opportunity to expand freely as it
would when inflating it outside the tire.

My experience with thorn-resistant tubes is that they are much thicker on the circumference than
they are on the rim-facing side. This causes them to stretch almost entirely on the inner face, with
the outer edge stretching only enough to take up the extra tire diameter.

Chalo Colina