With the advent of disposed syringes with hypodermic needles on the urban road sides and suburban parks and trails, there is an emerging concern about using finger drag tests for discovering hard to see causes of flat tires [to digress, not all causes of flat tires are immediately evident].
I've had ultra small wires, presumably from radial tires gone bad, that were so hard to find that no other method could discover the little source (and even then, the direction of the drag test mattered). While it hasn't happened to me, the source could easily have been a broken needle tip.
Does anyone know of any known solutions? I'm certain that gloves won't work - if they are too thick, one can't feel, and if the gloves are too thin, ... . Any workable Ideas?
Part 2: OK, Sorry, More Details:
1) Needle tips break rather frequently, often in patient arms, but especially when run over by vehicles.
1a) So not only is the needle a threat, so is the glass or plastic shard (but hold that issue for the moment).
2) Experience: Roughly about 80% of the source object cause of flats can be found very quickly (5 min),
maybe 18% can be found with a little diligence (15 min), but 1-2% are extremely difficult.
3) We're talking about that 2%, where one is on tour in the middle of nowhere,
biked through a town in the morning but remote camping tonight,
the kind where your tire goes flat over night and one, maybe, has already changed a tube at least once.
4) We know about where the object is (because of the same tube hole relationship mentioned in a response) but the offending object won't reveal itself except by pressure - This has actually happened to me, twice.
5) Until now, I've done the 'finger drag test' to find the object - Now I don't think that is smart.
6) What solutions exist?
7) I failed to mention that in my two tough flat tire cases, both times were on knobbies while on MTB tours.
In both cases I had to completely remove the tire and push the tire inward (on the tread) to stretch the insides.
[I moused over an icon and don't know how to rid of it.]
A) In the field, dragging a cloth or cotton ball seems logical and useful. Most people carry rags or maybe even use some article of clothing. Don't think that I've ever had a cotton ball.
B) In the shop, the Needle Stick sounds like a good idea (a whole new concept to me - thanks). It's probably a little more useful on the tread side of the tire; cotton ball or soft cloth for the inside.
C) Toilet Paper! Why didn't I think of that? Good idea!
A) The odds of a needle caused illness are slim, even remote, but not impossible. The issue is worthy of a query on a bike blog.
B) As for Needles Breaking and dealing with Broken Tips, I am happy for anyone that has never had to address such an issue. If one were to Google "Broken Hypodermic Needles" one will find way too many pages that address the issue of broke(n) needles.
Thank You Cyclists!