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45

I happened to do just that. I took an old hand pump and an inner tube to the bath tub. Submerged the pump and pre-filled the tube with water, complete with burping out any air bubbles. With the tube moderately full and free from air, I put it on the rim with the tire. Then the final pressure up. The first thing to notice is that the pump operates with ...


34

As you mentioned, one of the primary differences between a Presta and Schrader valves are the diameters--with Schrader valves being slightly larger--and therefore the valve holes on bicycle rims are drilled to suit one size or another. Your foremost concern with using a Presta valve in a rim drilled for a Shrader valve shouldn't be 'movement' of the valve ...


30

The cap keeps dirt and rocks away from the valve, particularly the fragile release mechanism. It's not the end of the world if the caps are missing, but I suggest leaving them on. They don't take that long to remove and replace.


27

I haven't tried them specifically with goatheads, but I've run through nails, staples, glass and just about anything else you could find in an urban environment on Schwalbe Marathon Plus tires. I have never had a flat over thousands of miles with their Marathon Supremes, either--and they're much lighter and better riding--but they're not as puncture-proof ...


25

Do yourself a huge favor, inflate them daily. As they are high pressure and low volume they tend to lose air quicker than that of a tube that is low pressure and high volume (MTB). With daily inflation checks you will vastly reduce the instances of pinch flats, which imo are typically the result of too low pressure. Butyl tubes, the typical tube, retain ...


22

I switched to using Specialized Armadillo a while ago because of frequent punctures, and I haven't had any since making the switch. I'd highly recommend them.


17

Inflating daily might be a bit more work that necessary. Inflate them before every ride. From my experience with 700x25c tires at 115 PSI, I find they lose about 5 PSI after 24 hours, just due to the natural properties of the rubber. I ride a few times a week, and it's part of my standard pre-ride checklist to give each tire about 3-4 strokes on the floor ...


15

Mark your tire where the tube's valve stem is located, remove the tube, inflate it and put it in a bucket of water. Look for bubbles. This is where your leak is. Now inspect the tire and rim at the correlating point for something that may be causing the leak. Good Luck.


15

This is a debate that gets picked up on every bicycle forum known to man (okay, that might have been exaggerating a bit). Typically you start to ask the question when you notice that the morning after you have used your CO2 cartridge, your tyre is ridiculously low. By no means am I a chemist but, as it has been explained to me, CO2 and butyl are more ...


15

If you're at home, use a floor pump. They are very easy to use and have a gauge so you can measure the pressure. When you're on the road, the quickest and easiest way to get you back on the road is to use CO2 cannisters. They are not that cheap though and the CO2 will leak out of the tube faster than air (mostly N2), requiring topping up over the next few ...


14

smaller hole in the rim is good (presta +) schrader has piece that inserts into the valve (screws in) with a spring mechanism to seal it - these parts sometimes fail (schrader -) presta uses tire pressure to seal it (presta +) rocks can lodge in uncapped schrader and cause leaks (schrader -) presta does not need a valve cap to keep rocks out (presta +) ...


14

Nobody has noted this yet, so maybe I'm particularly clumsy. The caps prevent you from bending the somewhat delicate presta valve stem if, like me, you're fitting a fairly beefy lock between your spokes every day. I smacked mine pretty good after a groggy morning commute, and it bent the valve stem pretty severely. They're somewhat known for snapping off ...


14

Baby powder works great and is very inexpensive.


13

It's not unusual for narrower tires to need pumping up every day or two, but if they really are losing air after "a few minutes" then the tubes have been holed somehow. Did anyone check the tires for small pieces of wire, etc, sticking in them? A tiny piece of wire can puncture a new tube within minutes. Did anyone check the rims to make sure that the ...


12

Just about any tire is going to be vulnerable to punctures especially as they age/wear. I've found the Continental Gatorskin tires to be effective and I match them with Mr. Tuffy tire inserts. As long as I check the tires for embedded thorns/glass every few weeks, I can go a few thousand road miles or more without a flat. The downside of using inserts and ...


12

They work ok - if you are just riding around town, they would probably be fine. If you are on a ride out in the middle of nowhere, I wouldn't count on these. The ones with glue work significantly better, to the point where I wouldn't by the glue-less ones.


12

The inner tube has no significant effect on max pressure. The valve stem area is the only area sensitive to pressure, and in general the valve can withstand 200 PSI or better. (And if you exceed whatever limit there is the result is "catastrophic" failure, not simply the inability to pump in more air.) What it sounds like you're noticing is the geometry ...


12

Note: this calculation makes many assumptions, so it's only useful in an 'average use case', not some sort of exact measurement. If you find better information, please post it and I'll update the answer. How many pumps you would need to fill up a tire depends on many variables. First, the volume of your inner tube, which can be approximated as a torus ...


11

Presta's main benefit is more about how the valve functions, in regards to getting pumped up to higher pressures. Because the stem of the valve needs pressure in the pump head to get high enough before it pushes the valve stem in, and start flowing air into the tire, when you try to get to 120 to 160 lbs of pressure it works better than a Schrader valve ...


11

http://alchemygoods.com/ They recycle inner tubes into usable products, and will give you credit towards their products for recycling.


11

Sometimes it can be hard to find a small hole. Sometimes it helps to mix water and dish soap together and either pour that over the partially inflated tire, scanning for leaks or submerging the tire in a bucket of soapy water. The soap will bubble and make holes more apparent. You also probably want to immerse the valve to see if the leak may be ...


10

If you're putting in 5 or maybe even 10 PSI every week, that's not too much out of line; it's normal for tires to lose a little bit of pressure over time. If your tires are sinking down to much more than that, you may have slow leaks. If both tires are decreasing by the same amount, perhaps you have older tubes that need replacing. If one tire is doing ...


10

I've use glueless patches for a number of tube repairs and have found them to be just as durable as the glued patches.


10

Check the label on the tube - does it say '26 x 1 3/8' by any chance? If so, this is actually a completely different size than the standard MTB 26". Get a tube that says something like 26x2.1 or 26x1.9 - the point is, the tire width should be expressed as a decimal, not a fraction. See Sheldon Brown's tire size chart. Yeah, I know, it's stupid - I didn't ...


10

This kind of failure is typically caused by excessive wear on the brake surface of the rim. Every time you apply your brakes, you are polishing small amounts of metal away from the rim. Eventually, the rim gets too thin and weak, and will crack, like you have seen in your photo, from the normal inflation pressure of the tire. In general, this means tht ...


9

How about recycling them yourself? Here are some ideas posted on the brilliant BikeHacks website. Shoelaces, wallet, yarn, handlebar tape, top tube passenger seat, dog lead, Maglite handlebar attachment, rack, key chain bling, bike bell, repaired bike seat...


9

A tube should not have excess length, and doubling on itself will cause the tire to feel uneven while riding, as well as increase the likelihood of flats. Assuming the tube is the correct size for the tire, as you said it was, there are 2 common causes for this problem. If you installed the tube without inflating it first, just a tiny amount, then it ...


9

I think that it is definitely worthwhile to patch a tube for many reasons: five patches go for about $5, lower than the price of a single tube (~$7). a patch kit can be taped under the seat whereas a tube must be carried in a bag or pocket (and if in a pocket, remembered). Given the ability to avoid flats almost entirely (e.g. using puncture-resistant ...


9

Schrader valve/Schrader tube aka "American valve" or "Automotive valve" The Schrader valve consists of a valve stem into which a valve core is threaded, and is used on virtually all automobile tires and most wider rimmed bicycle tires. The valve core is a poppet valve assisted by a spring.


8

Check inside the rim at the point where the punctures occur. Is the rim tape intact? Does a spoke push through when weight is placed on the bike? One of my friends had a problem like this, and it turned out that when he sat on the bike his weight caused the end of a spoke to push through the rim and puncture his tyre.



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