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36

Advantages: Fast - generally these fill up your tire much faster than you could with a pump Less effort - hook up, push button, no pumping Possibly less weight (but I haven't compared weight of smallest pumps to CO2) Lower initial investment - a valve and 2 cartridges generally seems to be cheaper than a good small pump. Disadvantages: Consumable ...


24

I'm surprised nobody else has mentioned this. Probably the most legitimate purpose of CO2 inflators for bicycles is for inflating tubeless tires. If you need to replace or repair a tubeless tire, chances are you will have zero luck inflating the tire if you try to use a hand pump. You either need to use an air compressor (good luck carrying that with you on ...


13

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 ...


13

Disadvantage: Environmentally irresponsible. It seems to me that there is a lot of energy contained within, and required to make, that CO2 cartridge for a single tyre inflation. I do carry one for emergencies 'in case of pump failure' but I try my best to never use it out of laziness.


12

Bike shops advertise them because they're consumable items. Every time you use a cartridge the shop is likely to make another sale. Whereas a good pump should last through many, many flats and is less likely to get good placement in the shop. For advantages/disadvantages, see freiheit's answer.


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 ...


9

The ideal gas law (which is a good approximation in this case) says PV=nRT where P is pressure, V is volume, n is mols of gas, R is the ideal gas law constant, and T is temperature in Kelvin. Thus, solving for n, we see n = (PV)/(RT). Then, assuming air is made up of {gas1, gas2,...} with fractions {p1,p2,...} (so p1+p2+...=1) and corresponding molar ...


8

Most likely this is a result of riding the tire while the pressure is too low. When you do that the tube tends to slide around in the tire and can get cut against the edge of the rim. However, this could also be the result of using a hand pump, which, if you don't "buck" it against something or hold the head steady will move the stem back and forth rather ...


8

Don't bother with an air compressor. Get a proper bike pump. They are cheaper, and will fill a tire to 60 psi with minimal effort. A good bike pump will also require less maintenance. Also it'll only take a couple pumps to top up your tires. Much less time than to drag out a big air compressor. Have you had problems with standard floor/track pumps? What ...


7

It is for adjusting the suspension on a medium to high-end mountain bike (fork), hence the lack of 'Presta' option. Since you will be returning it, to keep the shop happy and get what you really need, consider getting: A track pump with gauge and aluminium body. Look for one with a well engineered head that does Presta and Shrader valves. The easiest ones ...


5

A shock pump is designed to fill a very small volume of space with very high air pressures. A tire pump is designed to fill a large volume of air, to relatively low pressures, pretty quickly. You can technically fill a schrader valve tube using a shock pump, but because the volume of air for each repetition of the pump will be so low, it might take a week ...


5

The liters/minute capacity of a compressor says nothing about it's max pressure. Most compressors intended for air tool use are good to about 100psi, maybe 120, but you need to make sure before you spend your money -- the compressor needs to do maybe 30% higher pressure than your "target" pressure, or you'll be forever waiting for the tires to fill. But as ...


5

You're really asking two questions here: 1) Do road tires lose air more quickly? And 2) Do tubeless tires lose air more quickly? First off, let's talk about the different ways that tires can (and do) lose pressure. Obviously, they can lose pressure through a poor seal, either on the valve or where the tire seats to the rim on tubeless tires. Tires also ...


5

The CO2 inflater is, for me, only an emergency option. It lives in my saddle bag to get me home after a flat. I haven't rigorously investigated it, but anecdotally I think that tyres inflated with CO2 deflate by themselves more quickly than air-inflated tyres do. Fortunately I haven't punctured too much recently, but the last couple of roadside fixes with ...


4

The air we breathe is made up of 78% nitrogen (N2) and 21% oxygen (O2), with trace gases making up the rest. So the easiest comparison is between N2 and CO2. N2 is less dense than CO2 but otherwise they're very similar (to your tires) unless you somehow find yourself riding in temperatures near their liquidation points -- in which case you have bigger ...


4

The main benefit that I get from using a CO2 inflater over using a pump is time savings. The CO2 will fill your tire with air faster than a pump. I always carry a pump in addition to a CO2 inflater because the pump provides unlimited air. It's a good idea to be prepared to handle at least 2 flats so the pump is a nice backup. I would consider just ...


4

To calculate the weight of a gas you need the volume, pressure and temperature. A bike tyre is a torus (doughnut) with volume given by the formula: V=(πr^2)(2πR) where R is the radius of the wheel and r is the radius of the tyre. For a 700c25 tyre, R will be 311mm and r will be 12.5mm that gives a volume of 9.59×10^5 cubic millimetres or 0.000959 cubic ...


3

According to the people at Scott, the general weight limit for a rider is 110 kg. You are significantly above this, so the manufacturer doesn't necessarily support you on that. The wheels durability depends a lot on who built them and how well they were built and if they have taken any damage. You are in a YMMV (and at your own risk) range by sticking with ...


3

The visible strip sticking out from the top of the rim and inside the line is in fact the Chafer strip. This is on the tire to prevent the bead hook on the rim from cutting into the tire. The bead is the wire or in the case of folding tire such as the x'plor ush Kevlar ring on the edge of each tire. When seating the tire the bead is place inside the bead ...


3

That appears to be a standard flip-up chuck, and it claims to be "universal". If using on a Schrader valve you just push it on and flip up the lever. If using on a Presta valve you unscrew the knob on the Presta valve first, then push on and flip up the lever. With some of these you need to not push the chuck quite all the way on if using on Schrader. ...


3

I can't see your specific rims from here, but plenty of bikes back in the 70s and 80s had rims that width capable of handling 90-110 PSI. And I definitely wouldn't run a 1-1/8" tire at 65 PSI. I'd imagine that the rims, if designed for tires that narrow, should be able to handle 80 PSI or so.


3

I really like using the co2 canisters cause the're quick to pump up. Particularly for road bike, you can't get a road bike to 110psi using a hand pump. Most I've got is around 40psi with a hand pump. That pressure will let you limp home but certainly you can't continue on your merry ride with that pressue for fear of a low pressure flat. I've also now ...


3

Based on your edit, do this. Remove the wheel, deflate to about 10 PSI, then roll it along the ground, pressing down hard, for several revolutions. After you've done this examine the strip. Anywhere where the strip is not showing the "average" amount, tug on the tire to pull it out. Anywhere where the strip is showing too much, first examine the opposite ...


2

That depends... I usually carry inflaters AND a pump. I've had problems with both. The CO2 cartridges aren't too crazy expensive, but my most recent flat I used 2 of them and still ended up finishing with the pump. It's really easy to blow the CO2 out without getting it in the tire, and if that happens, you'd better have another cartridge to try, or a ...


2

Yep, it appears to be what it says (though not very clearly) -- a "shock pump", intended for pumping up shocks in bike suspensions, not for pumping up tires. And, frankly, I've never seen a "mini" pump that could do even a halfway decent job of pumping up high pressure tires. You need a full-sized frame pump to do it reasonably well.


2

at normal temperatures (human life temperatures) and pressures all gases behave about the same with temperature variation. Check out this article and the pressure tests of air, CO2, and nitrogen at the end: http://www.powertank.com/truth.or.hype/


2

With regard to your question over potential weight savings, I quickly weighed the kit that I normally use to give a comparison. The mini pump that I carry from Lezyne comes in at 83g (has some subtle modifications to stop it rattling); whereas the two unbrnaded 16g CO2 cannisters that I carry come in at 118g and require a chuck to use which is another 21g. ...


2

Inside the Presta pump head there will be a peg behind a rubber washer, which depresses the valve on the stem which is engaged when you move the lever into the elevated position. At the same time, typically a set of jaws will clamp onto the body of the stem holding it in place. It sounds very much as if your pump isn't able to activate the valve sufficiently ...


2

Road tires have higher pressure with lower volume, and both of those properties are going to cause them to lose air more quickly than a lower pressure, higher volume tire, tubeless or not. With that in mind, it may be the case that the tire needs a little more sealant. The stuff has to squeeze around not only throughout the casing of the tire, but also ...


2

If the guys who installed the tubeless tire didn't clean the rim and use sealant on the rim and tire before installing it, then it is likely losing excessive air. Tubeless tires run at a lower pressure than tube type tires...about 10 to 15 pounds per square inch less, so they need more attention than the tube type tires. I'd take the bike back and explain to ...



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