hey thanks, I might check that out

oh man that looks amazing! thought I wuz gonna die last week after about 4 hrs riding in super hot, super humid weather. if I didn't find water to jump into, I might not have made it home alive

I use Schrader valves. I'm a bit ham-fisted & they've always been kinda bulletproof for me. the inflator works fine. when I screw the cartridge on I don't hear any pop when it punctures the canister. I grasp it firmly & press it on the valve firmly & squarely. with Schrader valves I have to support the valve from the other side, pressing on the tire. which doesn't block the air. as soon as it inflates (which is almost instantaneously!) I take it off & test the pressure, either with a pinch or a gauge. if it needs more, I just press it on again. there's nothing to fuss with, screw the cartridge on & press against the valve. bingo bango I'm riding again

the cartridges come in diff. sizes

it was particularly useful one time when I had a slow leak. I was able to occasionally boost the inflation as I finished my ride. so convenient!

as cyccommute mentioned, the spring tension is tight. in fact, I thought my first unit got worse or wasn't fitting right, so I bought a 2nd & carry both. but they both work. they are tiny so I have to keep them in separate plastic zip bags, in my field repair bag, to be sure I don't lose them. 1 is by itself & 1 is w/ 2 cartridges

on epic rides I sometimes carry 4 cartridges in addition to my pump

on at least 1 occasion, I had 1 new cartridge be a dud. brand new, screwed it on, no gas. unscrewed it, no gas escape & it had a new hole from the inflator. I imagine new cartridge duds are quite rare but still, if you're gonna carry 1 you might as well carry 2

cartridges don't work when frozen so I keep them in my house during winter & carry them with me when I go out. they don't go in the winter bag they go in a coat pocket close to my body to stay at least a reasonable temperature

I also carry a small hand pump

you might want to test using it at home the next time you're swapping tires or something, so you have a feel for it. especially if you're using Presta valves, I think

If there were such a thing as a full-frame, spring-mounted pump with a folding foot-thing, 90 degree folding handle and a mounting spring lockout, with Zefal durability, that would be the bestest thing ever.

--Shannon

Now I'm wondering which works better against an aggressive dog: a whack with a pump or a face full of CO2? Discuss

DD

Length is close and, having run over a number of Zefal HP pumps because they popped out of the frame, the mount is far more secure. I bought my first Topeak Morph in 2000 and still have it. It still works and is going strong. I think it will last.

And it doesn’t rip valve stems out nor have to be pumped against a fence post or, worse, my knee to get to the proper pressure.

That's a skill thing (but it's ok if you can't learn it, different strokes etcetera, I know otherwise competent cyclists who are lost without indexed shifting); and pumps that have hoses have more places to leak.

As well, you can exert more force on the air column in the pump with it held between your hands than you can pushing down on the ground.

There are lots of skills that aren’t worth having because there are better ways of accomplishing the same goal that are easier. I have owned and used Zefal pumps. I know how to pump up a tire with one. I just choose to use an easier, less difficult method.

As to leaking hoses, hasn’t been a problem in 20 years of using one. Zefals, on the other hand, don’t work at all if you run over them…which I have done numerous times.

Um…no. Physics. When you push down into the ground, the maximum force is your body weight. When you push from one arm into the other, you can’t exert as much force. We don’t hold floor pumps between our hands and pump tires that way because we can exert as much force as our body weight.

I don't think that's correct.

Anyone who can do a pull-up is exerting more force than their body weight.

Squeezing a pump is, of course, not a pull-up; an exercise that is fairly similar to pumping is a chest-fly; average values for machine chest flys (flies?) quoted on the 'net show that any male more advanced than "novice" can exert more force than their body weight.

And if you did manage to exert more force on a floor pump than your body weight you'd be (briefly) doing a different kind of flying.

Of course, in a way this is all academic. All you need is a smidgen more than the pressure in the tyre - did you *really* need to get them up to 195 psi?

Not from what I’m seeing. MyFit.ca says that the average weight with a chest fly machine is 104 lbs they suggest starting at 50% of that for a novice. They also have a chest fly standard chart that lists weight for various levels of experience. You don’t get to more than body weight until intermediate level which they define as

A novice is defined as

Most people are going to be closer to a “beginner” in terms of arm strength. They are going to find driving the piston into the ground with their body weight than squeeze it.

What's the body weight of that 104 lb lifter?

They say “average”. I assume that’s over all weight ranges. I also assume that everyone who uses one of these machines isn’t using the maximum weight all the time.

A few more detail's from Heiko's Rebour archives on Flickr

https://www.flickr.com/photos/414206...7719190382423/

"FOR QUICK INFLATION"
This bottle filled with compressed air at 100 kilos allows you to largely inflate two tubulars to 4 kilos. Each bottle is tested at a pressure of 300 kilos before being put into service.
The right-angled connector, which does not change the rider's usual gesture, fits easily on all valves and has the advantage of not twisting the mechanism pins, provided of course that the connector is fully engaged on the valve. Simply screw the body on to open the bottle, and unscrew it to stop the compressed air outlet. The cylinder is provided with a centre point at each end for mounting on the bicycle frame itself.

always nice to see another Daniel Rebour drawing! I'm slowly making my way through Heiko's flickr pages.
I'm trying to figure out what a "kilo" translates into. I'm inclined to think it might be a kilopascal (kpa), but 4kpa is only 27.6 psi. I'm not sure how big the tubulars were back then, but 27.6psi seems quite low.
Of course, translation is always difficult, and especially when different eras and cultures are part of the translation. I like the comment "The right-angled connector, which does not change the rider's usual gesture", which I think means that the rider uses the same position/posture to use it as the rider would use when operating a Silca Impero pump. In the current culture in the USA, "the rider's usual gesture" suggests some sort of body language that is intended to send a message... probably not a happy message either, when fixing a flat.

Steve in Peoria

kgf/cm^2 ?

That’s 1400 psi. Not sure I’d want to carry around a bottle with that much pressure and an unregulated valve. It’s also going to take one hell of a compressor to fill them. CO2 cartridges are at about 800 psi.

It was my best guess. 4 kgf/cm^2 is still only 57 psi in those tubulars.

57 psi in a Clement Del Mondo silk would for sure get you home, and would probably ride pretty sweet...

--Shannon

Wonder how many vintage automobile drivers use hand pumps?

Bike Pros might disagree. The picture is copywrited 1996 but inflators have been around for quite a while. There’s a patent from 1954 but I can’t say that’s the first one.

My favorite dumb idea inflator is Genuine Innovations propane inflator. They call it “Big Air” probably because of the boost that the explosion gives you

My favorite dumb idea inflator is probably Stalin.

--Shannon

Close!

"Kilo" does not fit into the unit system of pressures in this context. As in Europe we use "bar" or "Pascal", it would either mean 4 kilobar (58015 Psi) or 4 kiloPascal (0.58 Psi).
1 bar = 100 kPa = 100000 Pa
1 Pa = 1 N/m² (apx 0.0981 kgf / m²)
1 bar = 100000 N/m² = 10 N/cm² (apx 0.981 kgf / cm²)

I would assume that Rebour is thinking in a different category in this text, that of ambient atmospheric air pressure.
Atmospheric air pressure (weather) is given a number in Europe that is around 1000. In a high pressure weather situation it is usually above 1000, in a low pressure situation it is below. The correct unit for this is millibar (mbar) or hectopascal (hPa).
So the "4 kilos" written in the text are surely 4000 mbar = 4 bar = 58 Psi.

In those days (1950!) racing bicycle tubulars on French roads were around 700x28c to 700x32c.

Yeah, usually I'm good about putting a "~" or "about" in front of approximations, forgot to this time.

Even though it's Earth-centric, I like the idea of referring to pressure in multiples of atmospheres. I wish it were done more.

I ride most of the time with a pump. Have for years but I did get a co2 inflator to top off the tire. The first one I had didn't have the control valve so when you screwed the cartridge on it was punchered and used up all the co2. Not very efficient. The second was this Silca one I got sometime in the late 80's or early 90's don't remember when.




I went on a ride with friends once with no pump just three cartridges, thought that would be enough. One of the other riders flatted three times and didn't have a pump so I let him use my inflator and cartridges. He bailed on the end of the ride, an unsupported century, and I flatted about twenty miles later. At this point I had been dropped by the other riders and no-one was answering my phone calls so I walked about two miles before they figured out something was wrong and came back for me.

Needless to say, I don't ride with out a pump anymore. Still carry the co2 but always carry a pump.