QUESTION: Recently I punctured. After I replaced the tube and pumped up the tire, I hadn’t gone 300 yards before the same tire flatted again. I was out of tubes so had to hitch a ride home. What’s going on? — Benny S.
RBR REPLIES: First, stop by your local bike shop and buy a tube repair kit. And ask how to use it if you’re not experienced. Keep it in your seat bag and you won’t be stranded again if you run out of tubes.
Whenever you flat, find out why. Don’t simply take out the punctured tube and stick in a new one. If a thorn or piece of glass caused the original flat, the sharp point is likely to be embedded in the tire casing. As you discovered, you’ll pump up the new tube and start down the road, only to hear that dreaded psssst.
During the repair, take the tire off the rim and gingerly feel inside the casing all the way around. Keep track by starting and ending at the tire label. Don’t rub your fingers too hard and get nicked. Some riders prefer to use a rag, which will snag on a sharp point, but fingers are less likely to miss it.
When you find the culprit, dig it out of the casing with your fingernail or a screwdriver tip from your multitool. Be sure to get it all.
I was in a similar situations. Frequent flats. In one instance, the tire had plenty of tread, but the sidewalls were weak due to age.. I installed new tires and that was that. In another case, I rode on 25mm tires inflated to 110psi. Over time, the rim strips got pressed into the recesses for the spoke nipples in the rim. Apparently, this caused the tubes to enter into those recesses and with the dilapidated rim tape the sharp edges of the holes caused punctures in the tubes. Remedy-replace the rim tape. Now I always inspect the rim tape carefully when tires are off the rims and replace when necessary. Use a good tape such as Velox. Make sure it’s the right width for your rims.
i had a double flat when I fixed the first puncture with one of those new rubber-cement-free patches. The air, as air will do, forced its way through the puncture under the patch, and out.
Maybe I applied the patch wrong. But, I practiced using the new kind of patch at home and thought I had it down. Or maybe it was just bad luck. Or roadside-repair brain fog. Or who knows what. I went back carrying an old-school patch kit with rubber cement. Too bad, those new patches are a great idea.
I double-flatted about 15 miles from home last year – similar story with a spare tube. Couldn’t find the offending sharp object. Had a patch kit but the glue had dried rock-hard (ok – attention to details is important.). I tied a knot in the tube and thumped my way home but it held air.
Here is AZ, many (most?) flats are caused by thorns (tumbleweed thorns often), These thorns (when in the tire) are tiny, hard to find and hard to remove as the head is often flat with the tire where a screw driver or pliers will not work). To remove the thorn, I carry a 6″ piece of spoke with one end sharpened to a point (use a grinding wheel) to “pick” out the thorn.
I carry tweezers in a pouch with other road items (chapstick, tire boots, electrolyte packets, ID, phone, etc). Thorns, wires, glass, etc. can be difficult to pick out with fingernails. If you have old eyes and don’t ride with corrective lenses, you might consider carrying a very small set of reading glasses.
Carry a Q-tip in your bag. Use it to check inside the tire casing instead of your finger. If there is a thorn, steel from a radial tire or piece of glass, the cotton catches an pulls. This is much better than cutting your finger.
I have picked up those infernal little pieces of glass that hide in the rubber of the tire. These seem to be a problem especially after a light rain that seems to make them stick to the tire. On new tires, I mark the side of the tube and the tire sidewall with a little typing correction fluid. I recently looked and looked for what caused the puncture in the tube and knew exactly where to look in the tire by lining up the marks. I put the marks in the same place when I reassemble the tube and tire, and so the patch is now where the embedded sharp is and will have to cut through the patch and tube to cause another flat.
Another trap can be a rim that has cracked or failed in the join, The tire will hold air until it is underload, ie ridden on. Very hard to detect.
No one asked where the leak in the tube was found, was it in the area where the tube is against the tire? if so all the advice was good; but what if the puncture was on the underside of the tube then what? Then it could have been the rim strip either wore out or a recent wheel truing got one of the spokes to go just barely touch the underside of the rim strip, then when the tube came under pressure and pushed against the rim strip it eventually caused a puncture.