tire pressure question

Too, I'd much rather be doing something physical to raise the pressure, versus standing/watching an electric 12 volt pump struggle.

 

Yep, I'm the same way with leaf blowers! I'm probably more talented with a broom and rake than anyone I've ever met. If they had raking and sweeping competitions I'd be right up there with the best of them. I have so many gardens and driveways I do this in and every time I find new ways to get better at it.

 

Oh I love my leaf blower. Being a corded electrical it's a bit of a task getting it ready. Not in the same league as gas, but no slouch.

I really hope corded-electric tools don't lose out to battery powered, I've seen some of the latter leaf blowers in action (maybe low end, to be fair), and they behave like glorified hair dryers.

Also, corded electric tools are cheap as dirt, and maybe more dependable than battery powered.. I see battery powered Milwaukee Wet/Dry, over a grand CDN lol.

Sorry for topic drift btw.

 

I got 10K additional miles out of my tires at 47psi in front and 45psi in rear... The wear was entirely even. It's a myth that a steel belted tire inflates like a balloon. The steel belts are more than enough to keep the surface flat.

 

People who use leaf blowers tend to be slobs... They think nothing of blowing all that debris into the street or the neighbors yard while kicking up a cloud of dust that can shorten the lifespan of your lungs while also being incredibly noisy.

When I'm done sweeping and raking the debris isn't turned into someone else's problem.

How many people would clean up their house with a leaf blower? If someone did do this, my reaction would be the same as the people who do this outside.

 

If it has rained recently, I have to take care that mine does not blow the live grass out of the ground.

 

It’s what kind?

 

The ones I use produce 1 psi per 7 strokes on my Prius tires, or per 10 strokes on my Subaru.

Knowing this, I can hit the desired top-up amount in a single try almost every time. Or just add a few extra strokes, then sometimes let out about a half pound.

 

I never have to worry about this with my rake & broom... What's more it's good cardio and the afterglow of that labor is way better that vibrating hands from using power tools, not to mention the fumes if you aren't battery based, and most important human lungs don't last very long if they breathe too much dust.

 

It's an early one from the EGO Power+ cordless line.

My rake sometimes pulls stuff up too.

I should probably add there's a walnut tree in back.

It drops walnuts. Then it drops leaves. Then it drops the twigs the leaves were on. Leaving giant mats of twigs.

The blower really does seem to move all that stuff out of the lawn with less trauma to the lawn than raking does. And it takes no time for the rake to get all clogged up with walnut twigs.

... and I do blow the stuff, slob-like, into (a tidy pile in) the street, where the city later comes along with a giant vacuum truck that I do not own one of, and slurps it up and takes it away.

 

Yeah I'm not averse to rake an' broom. Just every so often like how the leaf blower gets into all the corners, very effective. Use it for drying the car after washing, and blowing out the engine bay (poor man's compressed air).

We're hopelessly off-topic, btw. My bad...

 

Walmart sold a similar unit as @Mendel Leisk uses. It’s in the automotive section (I’d prefer one specifically labeled it can handle automotive tires, more volume than a bike tire). I loved those (red) things except eventually the cylinder portion would pop off the foot and that would be the end of it. (I sometimes check tires at around 4 something am and imagine the noise of a compressor to the poor neighbors). Eventually they started selling a much shorter version with a much wider diameter cylinder. (I assume for more durability). They may not have done their engineering homework as it’s extremely hard to pump air. I resorted to a dual mode AC/DC pump I purchased at Costco.

I second the Slime units @cyberpriusII mentions, I have two now:

Slime Digital Emergency Flat Tire Repair Kit - 50123 - Walmart.com

https://slime.com/collections/tire-repair-kits/products/pro-series-flat-tire-repair-kit

The second one I got from AutoZone but I haven’t tried it yet.

Their only negative that I know of is the screw on valve. As you unscrew air tends to leak out, skewing the accuracy of the built in gauge.

Pros: at least the first one from experience can be used as a pump, no need to waste/dispense the goo or worry whether it works with a dispensed goo can. (The one in my iQ was used and I could not get the compressor to work without it, at least not in my panic/rush). The goo does not expire like the expensive goo that Toyota sells, (MSRP higher than Porsche)! The one from Walmart claims 8 min and I can confirm from experience on a 295/35R20 tire it’s reasonably fast. (No “my pump pumps 1 billion cubic feet per second”, but that’s into outer space where there’s a vacuum), gimmicks that @ChapmanF alludes to. The Pro version claims 6 minutes on the label. There’s one thing that you also have to be careful of: Sometimes the manual of your new pump may have a surprise condition for you, “only use the pump continuously for x amount of minutes, after which allow to cool down for y minutes before using it again, or risk unwarranted damage.” Get one from a place you can easily return it if needed…

 

Different bicycle tires, in different uses, cover a much wider range of inflation pressures than passenger cars. Skinny road-bike tires may be (or used to be, before paradigms changed) pumped up beyond 120 psi, while fat snow-bike tires may be set as low as 1 psi in fresh powder snow. The full span in between is used by various other tires and conditions.

Considering that fewer people use manual pumps for cars than for bicycles, I believe you'll find a better selection of choices in the bicycle or sporting equipment department than in an automotive department.

Larger diameter pump cylinders do produce a higher air delivery rate, and are better suited to the higher volumes and lower pressures of fat tire bikes, but don't overdo it when selecting a pump for a car. For any given tire pressure, fatter pumps simply require more force to push the piston against the air you are compressing. This isn't a case of poor engineering, it is just basic physics. The consumer needs to select a size that they can work with.

My usual and favored bicycle pump has an outside barrel diameter just barely under 1-1/4 inch, and a gauge reading to 160 psi. Making assumptions about the wall thickness and inside diameter, that places the piston face very close to 1.00 square inch. So to reach 40 psi, it needs a bit over 40 pounds (plus some extra for friction and flow restrictions) pushing down on the handle. Reasonable for able-bodied people, though more of a workout for older and smaller people than young big ones.

But the same style pump stashed in my Subaru has a bigger barrel meant to deliver air faster. It has a 1-5/8ths inch barrel, chosen to be quicker for the larger volume and lower pressure of the Subaru tires, but is also harder to push at any given pressure. Its piston face is probably 1.75 to 1.8 square inches, so it would need more than 70 pounds on the handle to reach 40 psi. This is fine for a big (i.e. heavier) person like me, but a lot more fatiguing for smaller (lighter) people such as my spouse.

Under basic physics, the energy needed to fill a tire should be the same for either pump. The bigger one just needs more force for fewer strokes. But when human factors are included, the higher force causes more fatigue than a larger number of repetitions of a smaller force. Especially as body size goes down. At some point, smaller people simply can't produce the needed force.

For my use, that 1.25"-barrel bicycle pump is best for the Prius, and I would recommend against any fatter barrel for most people. For people weighing significantly less than me, e.g. average-sized females who aren't serious athletes, a slightly narrower pump, such as 1", may work better.

 

I found them I still have one of the older style and two of the impossible to use newer style. Outer diameter of the skinny one is about 4.2 - 4.3 cm. Outer diameter of the thick one is about 5.5 cm. I could bear my weight down (I’ve since gained more weight) and for 3x PSI of regular tire okay but around 50 PSI I’m guessing impossible for the thick one.

 

Both of those will be very difficult for getting common car tires up to full pressure. They are better for fat tire bicycles, ATVs, and other low pressure tires.

Get something skinnier for car tires, to keep the handle force tolerable. For better air volume per stroke, the cylinder should long, not fat, though that will be better for a pump left in the garage. A pump stored in the car trunk will need to be shorter, but must still be skinny.

 

I use a small portable compressor with a 0.5cf bottle built in, and a regulator. @ChapmanF helped me find it; it's a battery operated unit that shares batteries with a bunch of my yard tools.

Still works great and I actually just bought a new kit to extend the thing with various needles and cone tips to inflate balloons and kid toys. Many of those in my near future. I've been using it to inflate & top up all our car and bicycle tires, the garden equipment & snowblower tires for a while.

It's noisy but powerful and quick, easy to store & live with since it uses the same batteries as the mower & blower.

 

If you'll be pumping tires up to 35 psi, then a pump with a cylinder cross-section of 1 square inch will demand 35 pounds of force as you finish pumping. If it has a 2 square inch cross-section, you can pump the tire in half as many strokes, but you'll need 70 pounds of force as you finish. If it's a floor-standing pump and you weigh double that, probably that's a thing you can do.

I found a 12 volt DC compressor with a 23 amp permanent magnet motor and hardwired it, using the spare tire as its tank and a 60 psi pressure switch. So the spare is always at 60 psi if I need it, and now and then I'll hear the compressor topping it off. To fill other tires (or use a blowgun, or whatever), I just uncoil the hose from the little cubby in the left of the hatch. The compressor just stays put, nestled in the spare rim.

It's not whisper-quiet, but because it's kind of buried down under the hatch storage and clamped down, it doesn't make a racket, so much as a deep muffled hum.

 

Floor standing bicycle pump I'm using has barrel OD just over 31 mm, seems a good zone, not too strenuous. Called it 1.2" ID, and if my math didn't go off the rails, cross-sectional area around 1.13"

 

Don't know how tire pressure got to leaf blowers, but...

Did not have the time to read REALLY closely, but a few points.

SLIME inflators: Yes, as noted the "screw-on" bit of the SLIME products is a bit of a pain, but I got a short length of adapter from Amazon that solves that problem and it was pretty cheap, plus extended the length of the hose.

LUMITECO Locking Tire Chuck with Rubber Hose and Standard Tire Valve Fine Thread, Tire Inflator Pump Hose Adapter for Twist On Convert to Lock On Connection

Anyone that disses leafblowers does not actually have much leaf work to do....or they have a lot of time/energy on their hands,

I have a SunJoe corded leaf blower -- $25 on clearance from HD. A 60V battery powered blower from Greenworks and a backpack Stihl BR450.

The corder blower works O.K. Although sometimes it does not turn-on and it was that way from the start. Good for when the battery powered blower goes out. I mostly use the battery power on the sidewalks/paths around the house.

The Stihl is a beast. It takes what used to be three hours to four hours of raking down to 20-30 minutes. If I had the time/physical ability, I don't mind raking, but I don't. Plus, the blower -- if you know how to use it -- actually can be easier on the landscape in terms of NOT blowing gravel or not damaging bedding plants -- vs a rake -- again -- if you know how to use it,

The Stihl is a blessing.
kris

 

just don't over inflate your tires, above 40psi is just too hard.. some people claim that over inflating boost their MPGs.. yeah right..