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CO2 charger cartridges are used for bike tire inflation because they are a common, inexpensive product that has been around since the 1950s. Their other uses include powering air guns and inflating life vests. They were originally developed by the Crosman Corporation and marketed under the name "Powerlet". Powerlet cartridges are filled with CO2 presumably ...


35

A car tyre has much thicker rubber than a tubeless bike tyre, thicker still than a tube. The steel wires in the belts of a car tyre are impermeable to gas and occupy a significant fraction of the area of that layer. So there is a material difference. In both cases the rim can be regarded as impermeable, and the sidewall more permeable than the tread. Car ...


26

I believe you will find these articles informative: The hidden life of a CO2 cartridge [PDF] The CO2 Cartridge … an Under-Appreciated Marvel of Technology! — George Fox Lang [PDF] At room temperature (below the 31°C/87.8°F critical temperature) a CO2 bottle is to a practical extent self-regulating. This is not possible with simple compressed air. You ...


26

16 km/h is so slow that even the worst tyres should keep you up, unless something like oil spills were involved. If something is so slippy that you fall without warning at such low speeds there is not much one could do. If you have a hunch this might happen tripodding corners or getting off the bike may help. The first drizzle after a long dry spell can ...


19

One term: Mechanical advantage. You need a pump with the correct mechanical advantage. In the case of an air pump, the size of the piston defines how fast it does its job and how high a pressure you can put into a tire. Let's say your pump has an effective piston area of 1 square inch (6.5 cm²). That would mean that in order to pump 100 psi (pounds per ...


18

It can't burst the tube, because the tube is completely surrounded by the tyre and rim. Bear in mind, though, that higher pressures don't automatically mean a faster ride. There are two competing factors: a soft tyre is constantly losing energy due to being squashed flat against the road, but a hard tyre loses energy because any bumps you go over have to ...


16

In places where it rains very little or hasn't rained in a while and then a light rain falls, the water is not enough to "wash" the road surface; instead it only wets fine dust and oils that are on the surface. These oils come from cars' engines and exhausts, but are not noticeable at first sight. This mix turns into a fine, paste-like substance that is very ...


16

This study: William M. Bertucci, Simon Rogier & Raoul F. Reiser II (2013) Evaluation of aerodynamic and rolling resistances in mountain-bike field conditions, Journal of Sports Sciences, 31:14, 1606-1613, DOI: 10.1080/02640414.2013.792945 is very far from comprehensive, but it reports rolling resistances for two pressures (2 and 4 bar - 200 and 400 kPa) ...


15

As a heavy rider personally, I don't have many issues with flats. A normal tire on the high/maximum pressure works fine to avoid pinch flats. The key is to check tire pressure every time you get on the bike. Even a day will allow a tire to soften 10 psi, and that will allow flats to occur. Road hazard flats are not avoidable except by avoiding the ...


15

Sounds like the butyl rubber inner tubes have perished a little, and you have either a very slow leak, or a valve that lets the air out slowly. Just buy three new tubes from an online supplier - they'll cost about $5 each. Two to fit, and one to carry as the spare. You should also have two/three plastic tyre levers, a working pump, and whatever tools are ...


14

To fall to the inside of the turn means that the bottom of the wheel has slid to the outside. When that happens, it is really quick. I would look back at the corner and see if there's a metal plate in the roadway, which are terribly greasy when wet. Other possibilities include round grit/gravel/dust/sant that acts as a ball bearing, and oils on the ...


13

Each type and size of tire has a different pressure range. The range is written or embossed right on the side of the tire. The actual pressure you choose is dependent on what you are using the bike for, the road surface you ride on and your general preference. A safe choice the middle of the specified pressure range. Lower pressure will give a bit more ...


12

I presume you were riding in the direction you came across the bridge and down the ramp. I doubt tire pressure had anything to do with it. On a moutain bike sized tire, unless rolling tires of rims, too low tire pressure tends to cause imprecise handling and a general 'sloppiness' in the front end. "wiping out" as you did is not typically caused by low ...


10

No, not really. It is difficult to get an accurate idea of tyre pressure by pressing it. Especially for thin, high pressure road bike tyres - they should feel pretty hard. Even if they do feel hard, the pressure may be much lower than it should be. Best option is to get a good pump, with a built in pressure gauge. Many mini pumps will take a lot of effort ...


10

In addition to the previous answers, your tire pressure was likely too high for the conditions. If you know you're going to be riding in the rain, it's usually a good idea to lower your tire pressure from what you would normally have them at in dry conditions. A lower tire pressure allows the tire contact patch to deform more, thereby increasing the amount ...


10

I would expect lower tire pressure to give larger contact patch also when cornering so should equate to more grip in corners (assuming the tire stays on the rim). As correctly pointed out in another answer, increasing the contact patch does not increase optimal grip. However, a larger contact patch does give you a form of redundancy: if part of the ...


9

Short answer: no. The only fix is to mostly deflate the tyre (so it's just barely inflated, enough to hold it in place but soft enough that you can manipulate the bead) and work the slack in the bead around the wheel so that you have an even distribution. If you're really lucky there will be a matching place elsewhere that the bead has stuck in the middle ...


9

Your opening claim: Everyone knows (citation needed) that (at fixed rim diameter) tyres with smaller section require less effort to move around (at least on a paved road). Is actually not true. Your next claim isn't true either. The contact patch area for a tire will be nearly the same regardless of what width tire is used, for a given pressure. If I ...


9

After reading the answers here and becoming more curious, I found this article, which agrees with @Daniel. to briefly summarize it, they found that at the same tire pressure the narrower tires deflected more and had a lower stiffness (force over displacement) A curious finding is that a difference of 1 bar (14psi) makes more of a difference that a 5mm tire ...


8

DT Swiss publishes the exact document you are looking for: Manuals page / RIMS / Tire Pressure/Dimension (PDF) The document specifies the maximum usable tire pressure based on rim and tire width. More narrow tires allow for higher pressures. For example, the rims in the question (XR 400, inner width 18 mm) are compatible with tires ranging from 23 mm width ...


8

The maximum tire pressure should be written on the sidewalls. Often the embossed lettering is hard to read, shining a flashlight at an angle can give you the contrast to make it easier to read.


8

This explains part of the reason in what may be too much detail:http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch4/deviation5.html If you're going to read any of it, read the material starting after the table listing "van der Waals Constants for the Various Gases". It calculates that compressing CO2 from 1 Liters to 0.2 Liters using the Ideal Gas Law (...


8

The type of tire cracking that is most worrisome is when it's accompanied by bulging areas from the tube pressure. This implies damage to the casing, which in turn implies a tire that might very realistically fail at any time. The casing is the major structural part of the tire, not the rubber. Cracks in the rubber like this look bad but almost never result ...


8

Smaller tires need to be run at higher pressures to accommodate the same weight. You want to have enough air that the tire's rolling resistance is good but you don't get pinch flats / damage from appropriate road hazards. Too little/much air can affect control to some extent as well. If you have tubeless tires, you can usually run lower pressures (since ...


8

How wide are the tires compared to the rim? Wide tires at high pressure put stress on the rim’s sidewalls which can result in sudden, catastrophic failure. If the tires are relatively narrow it’s probably okay to over-inflate, but I doubt you’ll see much benefit. There are diminishing returns for rolling resistance. See for example this test of 56mm wide ...


8

I don't think your pressure should change based on tube material. Raising pressure just means that you're subtracting out whatever benefit you're getting from latex. Lowering pressure doesn't make sense because latex tubes are just as susceptible to pinch-flats as butyl tubes. There are different schools of thought on what the "right" pressure is, ...


7

The reason that rims have maximum tire pressures is because the tire presses out at the bead seat. This load is carried by the "bend" in the 'U' shape of the rim. Higher pressures put more stress on the rim and, given enough pressure, will cause it to fail either at the bend or perhaps through the spoke holes if that is the weak point. With rims designed ...


7

We don't do product rec here, but some general advice: You want to find the biggest tires you can fit into the bike, and run them at high pressure. The pressure written on the tire sidewall is useless (the maximum pressure depends on the rim and the tire), but in all likelihood you will be close to or exceeding it on many tires. The particular model of tire ...


7

Do a web search for tandem tires. A tandem bike carries two people, so typical loads are even bigger than you. Also, definitely use a pressure gauge. You may think you can tell by feel, but I ride every day and can't tell the difference between 80 and 100 psi.


7

I'd change it for a better tire, one that's much tighter on the rim. You inflated out to only 15 psi over its maximum. That kind of force could easily be generated in a quick turn with the brakes on. If the tire blows off in such a scenario, then you'll be underneath the vehicle you were trying to avoid. Go to your LBS, and explain that you want a ...


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