Modern Vespa

I have half a dozen different tire pressure gauges: dial, stick, digital, etc. When working with small scooter wheels, they all have this annoying habit of "hissing out" a couple of psi before the gauge gets properly seated to take a reading.

I try to apply the gauge square, so it doesn't happen every time. But often enough to be annoying. I hate it when checking the air pressure ends up being the cause for low air!

Anyways, just wondering if anyone has a favorite pressure gauge that works well for scooters, without any "hissing loss"?

Still looking.

I think that air gauge is found in the same aisle as frictionless bearings and weightless pulleys. However, all those items are always out of stock when I look.

Did you ever consider that it might be you?

Even on my FJR front wheel with large dual disks, I can usually get the gauge to seat with minimal air loss, if I take my time, get it lined up, and press with vigor. Not easy, but doable. I have a "Slime" brand electronic air gauge that I picked up at Target. Usually have to do some maneuvering to get it in position, but it holds the last reading, so no need to see the readout as you are applying it. Looks like Advance Auto still sells them fro around $12. The chuck is almost perpendicular to the gauge body, which make sit easier to get it on straight and press hard.

Damn you Heisenberg.

Yes, and no.

I mean, if it takes that much effort to get a good reading (and I agree with you it does), then I personally allocate that to a problem with the tool, not the human. But I agree many would call this "pilot error". And I get the impression a better mousetrap may not exist.

I was thinking of the Observer effect as I wrote my post!

Just over inflate your tyres a little bit.
Then hissing loss becomes satisfying adjustment.

TPMS?

https://innovationtire.com/product/tireminder-motorcycle-tpms-2-tire-kit/

The Bluetooth TPMS systems that screw onto the valve stems are dangerous and shouldn't be sold. The spinning weight imparts stress on the stems that were never designed for it, and on the back wheel they can easily slap against the frame and break even if they appear to clear at low speeds. When they break, the air leaks out of the tire quickly. I got a mile and a half on my 150 before all this became clear.

I now have car Bluetooth internal TPMS modules on five of my six scooter tires. They work well on four of those tires; the module stopped working on the fifth about two weeks after installation and I haven't re-dis-assembled the tire to deal with it. Internal Bluetooth TPMS is not a no-brainer; it is much more difficult to install a tire on a rim with the module installed, especially the small Vespa tires. And you have to fuss with an app and be moving in order to check the pressure.

As a result I am very neutral on these systems. If you have a garage compressor with a pump attachment that contains an integral gauge, every month you check the pressure you can be equipped to add air. This one, for example, is the gold standard:
https://www.amazon.com/gp/product/B0002SRL20/

That gauge goes to 160 PSI, with 2 PSI increments on the gauge. And I doubt it is accurate to that level. Not to mention the chuck would be entirely useless in the confines of a small scooter tire, unless you have offset stems.

A difference of 4 PSI is significant.

Your guess is at odds with my experience. The nozzle fits every tire I’ve tried it on except a tiny 4-inch tire from an electric kick scooter. It is accurate to 1-2psi in the range of all of the tires I’ve ever used it on, 20-60psi, to the limits of my technology. This is more than accurate for any amateur rider/driver. I’ve used these for decades and gifted them to every person I know with a compressor. They’re really good.

There's no way that'd fit between the disks on my FJR. Have you verified the indicated pressure with a different gauge? My eyesight, like everything else, isn't what it used to be. I doubt I could judge the pressure accurately to 1 PSI on that gauge. With my electronic gauge, easy, to a half-PSI.

I just got this for my garage, and I'm very happy with it so far.

https://www.amazon.com/gp/product/B07D3PVBJ4/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

It works fine with the straight valve stems on my Sprint, and I like that it clips onto the stem so I don't have to hold it in place while adding air. It can also be used as just a pressure gauge if you don't want to connect it to the compressor. Uses 2 AAA batteries.

I prefer the pistol grip setup for adding air, because I find the other style of trigger to be prone to pinching my hand. Ouch!

Yes, of course I verified the pressure with other gauges. That is the limit of my technology.

Tire pressure management is not a game of half-a-psi.

What is the deal with the snide titles - “no way,” “or not.” I’m relating my experience, you’re theorizing. If you have better gear to suggest for the OP, let’s hear it. Digital gauges feel precise but are not necessarily accurate, and they need batteries. I stopped using them a long time ago.

When I say "No Way" I mean there's no way to use that chuck on many of my bike and scooter tires. I have a similar long chuck, and a right-angle short chuck, and it's a trick even using the short chuck on some of them.

And I do tend to adjust my pressure to +/- .5 PSI. Might as well be accurate. I wouldn't settle for +/- 2 PSI.

If you are happy with your gauge, fine. I have no quibble with that.

My electronic gauges last 3 or 4 years, checking car, truck, scooter, and bike tires. I'm not even sure the battery is replaceable. I just get a new one when they quit working. They're between 10 and 15 bucks, so no great expense.

I combined an airtank with an inflator for off road tires 6-12 psi, replaced the gauge with 0-60 psi
The chuck fits in tight places, like a 10" scooter back tire & releases easily
https://www.amazon.com/gp/product/B01AO1ZBLW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

The big wheels on the liberty's make it easy to use a straight connector, like on this
https://www.walmart.com/ip/EVERSTART-Maxx-Jump-Starter-and-Power-Station-1200-Peak-Battery-Amps-with-500W-Inverter-and-120-PSI-Compressor-J5CPDE/908537063?wmlspartner=wlpa&selectedSellerId=0&wl13=2106&&adid=22222222227321447474&wl0=&wl1=g&wl2=c&wl3=399600055337&wl4=aud-1025747331496:pla-843835989725&wl5=9030890&wl6=&wl7=&wl8=&wl9=pla&wl10=8175035&wl11=local&wl12=908537063&veh=sem&gclid=CjwKCAiAnvj9BRA4EiwAuUMDf292-9TaEt-cZNBc2yXeuCvJZ0SShFdp9qAveNFi2BdZgWTpm-R9XhoCt74QAvD_BwE

Set the pressure & it shuts off
The display reads in tenths & seems to be in agreement with TPM on a subaru
The chuck is decent for a screw on...

I bought one of these: https://www.amazon.com/Topeak-Joeblow-Mountain-Floor-Pump/dp/B07C45V3JG

Pumping by hand isn't so bad, and unwinding a pressure hose, setting up a compressor and then putting everything away afterwards is a pain. This pump clips on the valve and the gauge reads out the pressure. It works. Not a day at the beach to clip it on sometimes but I get the job done.

If there was a Costco Tire Center convenient to me, that's where I'd air up. They have a nifty system where you key in the pressure you want, and it modulates the air until your tire gets there. Works so fast you doubt it did anything at all.

Seriously, buy a decent, manual, no battery, easy to read gauge and practice with it until you get it. TPMS is for my 20,000 lb RV, not my 250- 550 lb scooters

It's one of things that once you learn how to do it it's no big deal, but it is one of the most important things to do correctly.

Except for NASCAR and drag rails!

My wife heard my whining, and got me a "no hiss" Slime pressure as a stocking stuffer. Sound like what you were describing.

I haven't been riding due to snow, but I decided to try it out today anyways... Sure enough, no hiss!

We'll see how long the seal holds up, but I'll admit I was pleasantly surprised.

https://www.amazon.com/Slime-20475-Digital-Trucks-Bright/dp/B07V7GXSQV

My guess is that the problem is operator technique. May find some testers better or worse than others but biggest percentage of error is with the one holding it. My opinion. I use the Astro digital pressure gauge and really like it.

I solve all my tire filling problems by using a pancake compressor that I keep in a deck box on my front porch. The 50-ft hose will reach any vehicle in the driveway.

I have a tire chuck with an accurate built-in gauge on the hose end. It monitors pressure in real time, so I can easily slightly over-fill, then bleed off a little until I'm right on the money.

Easy-peezey.

I have a gauge that goes in-line with the air pump, so when you put it on, if some air leaks, out, you just add more and the gauge gives you a true reading. So all you loose is what little leaks out as you pull it off the valve stem. I'll try and find a link to it, I've had it for a while.

-Dan

Sounds interesting. I'm going to give it a try.

I've been using a Ryobi battery powered air pump. It seems to release without too much loss, tells me the pressure, and it's a pump too. I do tend to over inflate a bit, just to make sure. Plus I ride like an old man because I'm 65. I have better tires, better tech, newer scooter and I worry more. This whole "getting older thing" is really trying my patience.

It always works.

Never found the stick gauges like that to be particularly accurate, or even repeatable. Maybe I never spent enough money on one to get a good one (if they exist). Handy for a shirt pocket, though.

I mostly use a good bicycle pump, because I have no electricity in my garage. My brother gave a portable battery operated air compressor which is great for topping up.

Xiaomi Mi Air Compessor

Not entirely hiss-free and I would be worried about damaging the battery when stored in the pet carrier, but it fits well in there.

What i have (British made) is sufficiently accurate.

I love my JACO. Ive had it for 5 years now

90 degree valve stems help too

Good luck getting that thing onto the rear-wheel valve stem on an LX (unless you install a 90-degree stem).

After reading your experience, I ordered one of these as well. It does work as advertised - no hiss, no loss of pressure.