Re: patch insurance

hi Patrick!


On 12/Feb/11 19:29, PATRICK MOORE wrote:
> On Sat, Feb 12, 2011 at 6:47 PM, ernest breakfield
> <[email protected]>  wrote:
>> 1- i would never inflate a tube that isn't installed in a tire beyond the
>> low pressure it takes to give it shape for a couple of reasons; tubes get
>> stretched out to where they won't fit properly inside a tire any more if you
>> inflate them very much when not installed in a tire, and patches can easily
>> become dislodged from the tube they're supposed to be repairing as the tire
>> stretches but the patch doesn't.
> ??? "Elastic"? I routinely pump uninstalled tubes hugely to find small
> air leaks (yes, I know I can use water, but higher pressure and sound
> is easier) and I've never, ever, EVER found a tube to stretch beyond
> its original size -- and I've owned and used tubes for quite literally
> 10 years, adding over 2 dozen patches to them. No, your tube won't
> stretch and fail to return to its original shape, at least not so that
> you will notice.

     i can't agree; it would seem our experiences differ, but the 
benefit of a list like this is the sharing of those different perspectives.
     i've repeatedly seen tubes stretched from over-inflating, though i 
only recall letting it happen to me personally *once*.    ;-)
     in my experiences (mostly from witnessing the misadventures of 
others), tubes will stretch out, but not shrink back quite all the way, 
and it doesn't take much expansion for a traditional 23-32c tube to no 
longer fit properly in a tire (though i've seen the same thing happen to 
MTB-sized tubes). working support for multiple events over the years, 
i've seen this happen many times. i suppose it's possible that this 
effect would vary as tubes can vary, but i avoid the issue entirely by 
never over-inflating.

     personally i never use water to find small holes (as it's not 
typically convenient and i wouldn't want to have to wait for a tube to 
dry before repair), but rather do it by using very moderate pressure and 
turning the tubes past my cheek or lips; don't need to hear anything, 
and can detect even very slight holes with ease.


> Secondly, a well applied patch will rip the original rubber before it
> will separate, at least from a lightweight tube.

     i have *never* seen a patch rip a tube, but i'm no longer 
over-inflating tubes to where i'd see that.
     additionally, i'm patching tubes when they're barely or not 
inflated and/or at something close to their standard operating size so 
that the patches are applied with the tube is its normal size and fit best.


> I have plenty of practice: learned to make my own patches out of old
> innertube, age 10 or so, from sidewalk bicycle wallahs in New Delhi.
> Now, I live in goathead country and patch more in a month than many
> patch in several years, buy patches by the box of 100 and rubber glue
> in 4 oz bottles from Office Max. Not boasting, just confirming that I
> know from patches.

     sounds really interesting, but like a bit more than i carry; could 
explain some of the differences we're seeing in patches.    ;-)
     i'm typically using something like the typical Rema Tip-Top patches 
because (if they're used properly) they can't be felt in the tire after 
a repair. i consider any patch job that's detectable when riding it a 
failure.

     Goatheads; i know that's more of an issue in some areas, and i 
don't envy you that.
     i don't deal with those except on the bikes i ride off-pavement; on 
some of those bikes, i use tubes with a tire sealant, and just don't 
have issues with Goatheads any longer. i've pulled several thorns at a 
time out of a tire and usually pull a couple of dozen thorns or more out 
of a tire before they will fail to re-seal. yes, they're a little more 
expensive and a little bit heavier, but every thorn i pull out and watch 
seal up is another instance of me not having to stop to fix a flat when 
i'd much prefer to be riding. (FWIW, i've found the Specialized sealant 
tubes to work better in general than the Slime brand.)


cheers!
e