Bike pump maximum pressure.
#1
Senior Member
Thread Starter
Bike pump maximum pressure.
I have an Axiom Expandair HV.
How many pounds pressure should it be able to pump in an ordinary Hybrid tire?
The most I have been able to pump is thirty pounds. I know that is probably
the max but it seems very low to me. My tire max is 80 pounds.
I run seventy. Maybe I can run on thirty until finding a
more powerful pump but it would be nice to have fifty.
How many pounds pressure should it be able to pump in an ordinary Hybrid tire?
The most I have been able to pump is thirty pounds. I know that is probably
the max but it seems very low to me. My tire max is 80 pounds.
I run seventy. Maybe I can run on thirty until finding a
more powerful pump but it would be nice to have fifty.
#3
Senior Member
Thread Starter
I pumped for a darn long time to get thirty.
Pumping two or three times as long would be quite the task.
As you suggest I have a very good floor pump in mind.
The reason I used the Axiom is it was for a flat on the road.
#6
Really Old Senior Member
I carry a cheap Bell pump and a couple CO2 cartridges for the road.
Use the cheap pump basically to get the bead seated properly and up to "some" pressure and then finish off with the cartridge.
If it get's stolen, it's much smaller loss.
Use the cheap pump basically to get the bead seated properly and up to "some" pressure and then finish off with the cartridge.
If it get's stolen, it's much smaller loss.
#7
Senior Member
Thread Starter
I guess this gets chalked up to experience.
At least I know what the answer is anyway.
The pump is small so good for emergency road flats.
#8
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If you are only going to 70psi on your hybrid, you can find a number of pumps, even at Walmart, that will work. I use a good SKS high pressure floor pump for my road bike, but I have an inexpensive Performance (Spin Doctor) floor pump for my mountain and commuter bikes. No need to spend a lot on a 160psi pump when you won't see half of that.
John
John
#9
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For on the road, if you can find a way to mount an old-fashioned frame pump, you can get any Zephal HPX or "Classic" pump and have a pump that will last you years, hundreds of pump-ups and will easily get you to any pressure you want. Tires a large as yours will take a few more strokes but getting far more pressure than you actually want to ride with will not be a challenge.
Ben
Ben
#10
☢
The most I have been able to pump is thirty pounds. I know that is probably
the max but it seems very low to me. My tire max is 80 pounds.
I run seventy. Maybe I can run on thirty until finding a
more powerful pump but it would be nice to have fifty.
the max but it seems very low to me. My tire max is 80 pounds.
I run seventy. Maybe I can run on thirty until finding a
more powerful pump but it would be nice to have fifty.
#11
Senior Member
The only pumps I generally have had trouble with is the ones that take CO2 cartriges. Do they work properly at all? Some of the mini pumps I have had hasn't lasted long in use, but generally they have be fine. Any basic pump should be up to filling max pressure in a tire, if not, just get another, return it if a new one doesn't work properly. A few things that can act up; the rubber seal not properly in place, the locking lever that closes around the valve has to be in correct position to work; it differs from brand to brand. Maybe someone can lend you a pump until you find one that works. Some pumps are easier with presta valves than others. Sometimes the valve mechanism can be a bit stuck, but usually it comes around after a few attempts.
#12
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The laws of physics can't be violated no matter who makes the pump.
The maximum pressure you can attain with any pump is determined by the diameter of the barrel and how hard you are able to push. If your pump has a 1 square inch barrel diameter and you want to achieve 100 psi, you have to be able to push down with 100 pounds of force.
Inflating a tire adds volume to the equation. A fat tire, for example, takes a lot of volume so a pump with a long stroke will take many fewer strokes to inflate your tire than a itty bitty short stroke mini pump. (Mini pumps essentially suck.). A skinny tire has less volume but generally needs more air pressure so you're better off with a pump that has a skinny barrel that's will be easier to push. A pump with a 1/2 square inch diameter will only take 50 pounds of push to get to 100 psi. (Mini pumps will still suck because they take so many strokes.)
The good news about mini pumps is that they only suck when you have to use them. If you don't get very many flats and you have a kind of zen demeanor when things go badly, the compact size of a mini pump may very well suit your needs.
The maximum pressure you can attain with any pump is determined by the diameter of the barrel and how hard you are able to push. If your pump has a 1 square inch barrel diameter and you want to achieve 100 psi, you have to be able to push down with 100 pounds of force.
Inflating a tire adds volume to the equation. A fat tire, for example, takes a lot of volume so a pump with a long stroke will take many fewer strokes to inflate your tire than a itty bitty short stroke mini pump. (Mini pumps essentially suck.). A skinny tire has less volume but generally needs more air pressure so you're better off with a pump that has a skinny barrel that's will be easier to push. A pump with a 1/2 square inch diameter will only take 50 pounds of push to get to 100 psi. (Mini pumps will still suck because they take so many strokes.)
The good news about mini pumps is that they only suck when you have to use them. If you don't get very many flats and you have a kind of zen demeanor when things go badly, the compact size of a mini pump may very well suit your needs.
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Last edited by Retro Grouch; 05-22-18 at 07:32 AM.
#13
Senior Member
I had a flat yesterday and used my Topeak Road Morph G for the first time in a while. I was surprised at how easy it was to get up to 100psi with it, based on the gauge. If I could only have one pump that would be it as it works easily enough that it could do as a home pump. I had the flat fixed in 2 traffic light cycles, so it was quick, no tools required except the pump.
#14
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The laws of physics can't be violated no matter who makes the pump.
The maximum pressure you can attain with any pump is determined by the diameter of the barrel and how hard you are able to push. If your pump has a 1 square inch barrel diameter and you want to achieve 100 psi, you have to be able to push down with 100 pounds of force.
Inflating a tire adds volume to the equation. A fat tire, for example, takes a lot of volume so a pump with a long stroke will take many fewer strokes to inflate your tire than a itty bitty short stroke mini pump. (Mini pumps essentially suck.). A skinny tire has less volume but generally needs more air pressure so you're better off with a pump that has a skinny barrel that's will be easier to push. A pump with a 1/2 square inch diameter will only take 50 pounds of push to get to 100 psi. (Mini pumps will still suck because they take so many strokes.)
The good news about mini pumps is that they only suck when you have to use them. If you don't get very many flats and you have a kind of zen demeanor when things go badly, the compact size of a mini pump may very well suit your needs.
The maximum pressure you can attain with any pump is determined by the diameter of the barrel and how hard you are able to push. If your pump has a 1 square inch barrel diameter and you want to achieve 100 psi, you have to be able to push down with 100 pounds of force.
Inflating a tire adds volume to the equation. A fat tire, for example, takes a lot of volume so a pump with a long stroke will take many fewer strokes to inflate your tire than a itty bitty short stroke mini pump. (Mini pumps essentially suck.). A skinny tire has less volume but generally needs more air pressure so you're better off with a pump that has a skinny barrel that's will be easier to push. A pump with a 1/2 square inch diameter will only take 50 pounds of push to get to 100 psi. (Mini pumps will still suck because they take so many strokes.)
The good news about mini pumps is that they only suck when you have to use them. If you don't get very many flats and you have a kind of zen demeanor when things go badly, the compact size of a mini pump may very well suit your needs.
The Topeka Morphs, Lezyne Micro, Axiom EnforceAir or any of a number of minifloor floor pumps improve the minipump pump significantly as well as being vastly better than frame fit pumps. The plunger is pumped horizontally like a floor pump so that the user can put more force on the air being compressed and thus have to work less. You also don't have to stabilize the wheel while pumping so you can concentrate on pumping. I bought my first Topeak Morph (I have around 10 of them now) about 20 years ago and I haven't regretted it for a minute.
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Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School When It Wasnt Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
#17
Senior Member
Thread Starter
You are only partly right. It's the wrong pump, period. This is a little pump with a small volume and poor ergonomics.
I would add that the other problem is how you have to pump. With this pump, the plunger is moving horizontally so the maximum force you can put on it is what you can squeeze between your arms. Add in the need to stabilize the wheel and the natural movement of your arms and you have a recipe for inefficient pumping. I would also suspect that most people don't ram the plunger all the way to the bottom of the shaft and are only compressing the air but not getting much into the tube.
The Topeka Morphs, Lezyne Micro, Axiom EnforceAir or any of a number of minifloor floor pumps improve the minipump pump significantly as well as being vastly better than frame fit pumps. The plunger is pumped horizontally like a floor pump so that the user can put more force on the air being compressed and thus have to work less. You also don't have to stabilize the wheel while pumping so you can concentrate on pumping. I bought my first Topeak Morph (I have around 10 of them now) about 20 years ago and I haven't regretted it for a minute.
I would add that the other problem is how you have to pump. With this pump, the plunger is moving horizontally so the maximum force you can put on it is what you can squeeze between your arms. Add in the need to stabilize the wheel and the natural movement of your arms and you have a recipe for inefficient pumping. I would also suspect that most people don't ram the plunger all the way to the bottom of the shaft and are only compressing the air but not getting much into the tube.
The Topeka Morphs, Lezyne Micro, Axiom EnforceAir or any of a number of minifloor floor pumps improve the minipump pump significantly as well as being vastly better than frame fit pumps. The plunger is pumped horizontally like a floor pump so that the user can put more force on the air being compressed and thus have to work less. You also don't have to stabilize the wheel while pumping so you can concentrate on pumping. I bought my first Topeak Morph (I have around 10 of them now) about 20 years ago and I haven't regretted it for a minute.
That is just Traditional Archery. The real total is much higher.
I actually enjoy that kind of labor and do pump in an efficient manner but I see your point.
Unfortunately unless I do a lot more long distance riding,
I can't justify replacing that almost new pump. At least now with all the help
I know the pumps limitation.
Last edited by PdalPowr; 05-22-18 at 10:47 AM.
#18
Senior Member
Thread Starter
I do have a Zen demeanor when it comes to my bike.
I am sorely impatient when driving my car but
cruise through life complacently in the granny gear when on my bike.
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#19
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...
I would add that the other problem is how you have to pump. With this pump, the plunger is moving horizontally so the maximum force you can put on it is what you can squeeze between your arms. Add in the need to stabilize the wheel and the natural movement of your arms and you have a recipe for inefficient pumping. I would also suspect that most people don't ram the plunger all the way to the bottom of the shaft and are only compressing the air but not getting much into the tube.
...
I would add that the other problem is how you have to pump. With this pump, the plunger is moving horizontally so the maximum force you can put on it is what you can squeeze between your arms. Add in the need to stabilize the wheel and the natural movement of your arms and you have a recipe for inefficient pumping. I would also suspect that most people don't ram the plunger all the way to the bottom of the shaft and are only compressing the air but not getting much into the tube.
...
The secret for a good horizontally pumped pump is 1) length (get the biggest one you can fit on your bike), small diameter and good ergonomics. There are other good pumps out there, but I stick with Zephal because they nailed those three 45 years ago. The pumps have only improved since.
Edit: I got reminded every time I pumped a tire that, yes, this was one of the few upper body exercises we cyclists do.
Ben
Last edited by 79pmooney; 05-22-18 at 11:05 AM.
#20
don't try this at home.
Short, small pumps are slow. But they are tiny and lightweight, so maybe the tradeoff is okay.
I have a Topeak Mini Morph, the shorter version of the Morph pump. These pumps, with a hose and one end of the pump on the ground, allow much higher force on the pump handle as the pressure rises. And it's much less likely to damage the valve stem when pumping.
On road bike tires, I counted about 200 strokes to get to maybe 70 psi, enough to finish the ride. For the last 50 strokes, I had to lean into the pump with a stiff arm and my body weight.
I rarely get flats, so the smaller size works for me. (and I usually carry CO2 now.) Other riders have used longer Morph pumps, and those are much faster than the Mini.
Mini Morph:
I have a Topeak Mini Morph, the shorter version of the Morph pump. These pumps, with a hose and one end of the pump on the ground, allow much higher force on the pump handle as the pressure rises. And it's much less likely to damage the valve stem when pumping.
On road bike tires, I counted about 200 strokes to get to maybe 70 psi, enough to finish the ride. For the last 50 strokes, I had to lean into the pump with a stiff arm and my body weight.
I rarely get flats, so the smaller size works for me. (and I usually carry CO2 now.) Other riders have used longer Morph pumps, and those are much faster than the Mini.
Mini Morph:
![](https://cimg5.ibsrv.net/gimg/bikeforums.net-vbulletin/400x351/mini_morph_278873a823a7abaaeca4ae35558675c5f8c0e370.jpg)
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