Tire pressure gauge

[Ken R]

Today, I checked the air pressure in my Titan truck.  One tire was really low.  I aired up all four to 40 PSI and took the truck to Discount Tire Company.  They fixed a puncture in the one that was low.  Then, they checked the pressure in the three others.  They were all at 35 to 36 PSI!   This is cause for concern because I trusted my gauge/filler.     

This is the tool I own:  Air Gauge/Filler

So as soon as I got home, I checked a couple of the Titan's air pressure with my gauge.  Now, the gauge indicates 43 to 44 PSI.   
Then, I checked every air gauge I own.  The Harley Davidson air shock pump with integral gauge most closely matched the Discount Tire air pressure on the truck.  My other el-cheapo gauges measured differently by differing amounts.

Then I check the rear tire on my Ultra Limited with the HD pump/gauge.  It read 35 PSI.  (I'd filled to 40 PSI a few weeks ago, before going to South Dakota).  Front tire read 30 PSI.  It's really hard to get a gauge or a chuck onto the valve stem on these new motorcycles; the HD Pump/Gauge doesn't lose any air becaue it's screw-on and seals well. 

So I've been riding for maybe years with under-inflated tires. 
Wondering what under-inflation by 4 to 5 PSI affects.  Handling?  Stability? Mileage? Tire wear? Safety? 

Ken

[Tsani]

Don't forget that as you check the pressure, you will lose a bit so it will be less when you do it again.

[harleyjt]

Today, I checked the air pressure in my Titan truck.  One tire was really low.  I aired up all four to 40 PSI and took the truck to Discount Tire Company.  They fixed a puncture in the one that was low.  Then, they checked the pressure in the three others.  They were all at 35 to 36 PSI!   This is cause for concern because I trusted my gauge/filler.     

This is the tool I own:  Air Gauge/Filler

So as soon as I got home, I checked a couple of the Titan's air pressure with my gauge.  Now, the gauge indicates 43 to 44 PSI.   
Then, I checked every air gauge I own.  The Harley Davidson air shock pump with integral gauge most closely matched the Discount Tire air pressure on the truck.  My other el-cheapo gauges measured differently by differing amounts.

Then I check the rear tire on my Ultra Limited with the HD pump/gauge.  It read 35 PSI.  (I'd filled to 40 PSI a few weeks ago, before going to South Dakota).  Front tire read 30 PSI.  It's really hard to get a gauge or a chuck onto the valve stem on these new motorcycles; the HD Pump/Gauge doesn't lose any air becaue it's screw-on and seals well. 

So I've been riding for maybe years with under-inflated tires. 
Wondering what under-inflation by 4 to 5 PSI affects.  Handling?  Stability? Mileage? Tire wear? Safety? 

Ken

So I guess my question is why do you think the tire company's gauge is the correct one?  Yours may be the accurate one and you may now be over-inflated.   Herein lies the problem as I see it.  There's no really good way to validate a gauge nor calibrate it even if it is found to be off.
jt

[LexKing]

This is pretty much the reason that I purchased the gauges that I use and the accuracy information is as follows:

The dial tire gauges are ANSI Commercial Grade B gauges (meets ANSI B40.1 Grade B specifications), which is the best quality gauge typically used for tire pressure applications. These tire gauges use a fully geared, solid brass precision movement with bronze bourdon tube. Unlike piston-plunger-type gauges, the bourdon tube movement is not affected by changes in temperature, humidity, altitude or air stream contaminants.  The mechanical accuracy rating is ± 2% from 25% to 75% of scale and ± 3% below 25% and above 75%.

Motorcycle: The 60 psi tire gauge is accurate to +/- 1.2 psi from 15 to 45 psi and is calibrated to ± 1 psi at 30 psi.
Car / Truck: The 100 psi tire gauge is accurate to ± 2 psi from 25 to 75 psi and is calibrated to ± 1.5 psi at 50 psi.
   

[Ken R]

Today, I checked the air pressure in my Titan truck.  One tire was really low.  I aired up all four to 40 PSI and took the truck to Discount Tire Company.  They fixed a puncture in the one that was low.  Then, they checked the pressure in the three others.  They were all at 35 to 36 PSI!   This is cause for concern because I trusted my gauge/filler.     

This is the tool I own:  Air Gauge/Filler

So as soon as I got home, I checked a couple of the Titan's air pressure with my gauge.  Now, the gauge indicates 43 to 44 PSI.   
Then, I checked every air gauge I own.  The Harley Davidson air shock pump with integral gauge most closely matched the Discount Tire air pressure on the truck.  My other el-cheapo gauges measured differently by differing amounts.

Then I check the rear tire on my Ultra Limited with the HD pump/gauge.  It read 35 PSI.  (I'd filled to 40 PSI a few weeks ago, before going to South Dakota).  Front tire read 30 PSI.  It's really hard to get a gauge or a chuck onto the valve stem on these new motorcycles; the HD Pump/Gauge doesn't lose any air becaue it's screw-on and seals well. 

So I've been riding for maybe years with under-inflated tires. 
Wondering what under-inflation by 4 to 5 PSI affects.  Handling?  Stability? Mileage? Tire wear? Safety? 

Ken

So I guess my question is why do you think the tire company's gauge is the correct one?  Yours may be the accurate one and you may now be over-inflated.   Herein lies the problem as I see it.  There's no really good way to validate a gauge nor calibrate it even if it is found to be off.
jt

Good question.  That's why I went directly home and checked with every gauge I owned on the tires that they pressurized.  I have two or three that agree with Discount Tire.  None read less pressure.   The rest of mine all read 3 to 5 pounds high, including the one on which I've always depended.
(Theirs is an automated system with a digital read-out.  Enter the pressure desired on the panel and it goes there and displays the progress s it inflates the tire). They could all be wrong, of course, including Discount Tire's. 

[a2wheeler]

Reading thru the comments I now feel the need to check the gauge accuracy of the one that has been rattling around in my tourpak for 8 years. It was once accurate, but I should check again.

[Ken R]

This one, LexKing?

http://www.getagauge.com/Accu-Gage-HSeries.cfm

$14.50 doesn't sound like enough for a quality instrument. 

It does look like the chuck will fit between the spokes of the cast wheels. 

Ken

This is pretty much the reason that I purchased the gauges that I use and the accuracy information is as follows:

The dial tire gauges are ANSI Commercial Grade B gauges (meets ANSI B40.1 Grade B specifications), which is the best quality gauge typically used for tire pressure applications. These tire gauges use a fully geared, solid brass precision movement with bronze bourdon tube. Unlike piston-plunger-type gauges, the bourdon tube movement is not affected by changes in temperature, humidity, altitude or air stream contaminants.  The mechanical accuracy rating is ± 2% from 25% to 75% of scale and ± 3% below 25% and above 75%.

Motorcycle: The 60 psi tire gauge is accurate to +/- 1.2 psi from 15 to 45 psi and is calibrated to ± 1 psi at 30 psi.
Car / Truck: The 100 psi tire gauge is accurate to ± 2 psi from 25 to 75 psi and is calibrated to ± 1.5 psi at 50 psi.

[boooby1744]

NAPA pencil.................check this article,it compares several gauges against an  accurate reference :

http://www.mcnews.com/mcn/technical/200511gauges.pdf

[LexKing]

This one, LexKing?

http://www.getagauge.com/Accu-Gage-HSeries.cfm

$14.50 doesn't sound like enough for a quality instrument. 

It does look like the chuck will fit between the spokes of the cast wheels. 

Ken

Yes, that's the one Ken.  Here is a better picture and link of the Motorcycle Gauge - Picture/Link with the rubber protection ring.

boooby174; Thanks for sharing the article. It looks like my car/truck tire gauge even made the recommended list for motorcycles. I do plan on picking up one of those NAPA #90-378 to carry in my windshield bag on the bike. This will most-likely replace the H-D Mini currently on board.

[tdkkart]

 I bought a Harley Digital model about a month ago partially because I was amazed that it was only $29.95 rather than the $69.95 I expected, considering it had the Bar and Shield and the Harley Davidson name all over it.  Seems to work OK. A BIG consideration with the newer bikes comes down to if it will actually fit on the valve stem. Checking the rear tire on my new RGU is near flippin' impossible without standing on your head and having an additional wrist installed in your arm.

[LexKing]

I have had one of the HD dial gauges for several years. I got it free, as a promotional item, if you buy several dollars worth of parts in the spring. It even came with a tread depth indicator, chrome braided hose and a carry case. It works pretty good, but like you I found that the angle head was problematic.

$14.50 doesn't sound like enough for a quality instrument.

Kens comment, along with yours, makes me think that if the previously referenced gauge had "Harley Davidson" printed on it, it would surely cost another $50 or so. Call it $69.95, sound about right?

[Ken R]

This one, LexKing?

http://www.getagauge.com/Accu-Gage-HSeries.cfm

$14.50 doesn't sound like enough for a quality instrument. 

It does look like the chuck will fit between the spokes of the cast wheels. 

Ken

Yes, that's the one Ken.  Here is a better picture and link of the Motorcycle Gauge - Picture/Link with the rubber protection ring.

boooby174; Thanks for sharing the article. It looks like my car/truck tire gauge even made the recommended list for motorcycles. I do plan on picking up one of those NAPA #90-378 to carry in my windshield bag on the bike. This will most-likely replace the H-D Mini currently on board.

Ordered one for my workshop.  Will used the closest-reading pencil type for the road.

[Evo160K]

Repeatability of the gauge is more important to me than accuracy.  I subscribe to the thinking a tire should not expand more than 10% from cold to hot, an Avon rep offered that.  He said, if the pressure increases more than 10%, the tire was too low cold, the sidewall flexed more than it should have and  created heat.  Within the 10% is ample room to adjust for personal preference.  Bottom line, if the gauge is off the same amount repeatedly, it will work for me.  I suggest most of us know our primary bike so well, we can feel when a tire is too low, particularly the front.

[texaskatfish]

Garry & 04Glider - I ordered one of those cycle gear units

THANKS!

Just received this gague - IMHO a high quality unit! My only addition to it would be a 90* fitting instead of the 45* it comes with

[MaxxV4]

Hey Ken R:
Remember all those gas mileage tests you were doing?
Dang! Looks like you have to start over. (LOL Just kidding)
Mike

[Ken R]

Hey Ken R:
Remember all those gas mileage tests you were doing?
Dang! Looks like you have to start over. (LOL Just kidding)
Mike

Yeah, looks like it. 
My new gauge arrived today.  Haven't tested it yet, but it looks like it'll easily fit between the cast wheel spokes.  It's a nice looking gauge.
Now I need to compare it to all the rest.
Ken

[08FLHTC]

I also have used the Accu-gage from http://www.getagauge.com for several years.  Go on line to www.getagauge.com and you can order the gauge with any features (Including pressure range) you desire, including the right angle chuck.  I highly recommend you include the $3.00 rubber housing cover to mitigate riding (or dropping) shocks.  They are in the $20.00 range depending on type and features.  I also ordered one for my RV, except it is the 100 PSI version with the double ended chuck for the duals.

[Rockymtnglide]

I have used the Roadgear digital gauge for a couple of years now. Works well.

http://www.roadgear.com/digital-tire-gauge-p-40.html

[Dennis The Menace]

As much as I hated to - I bought the HD dial gauge with a hose on it. It works great, appears to be accurate (just comparisons with other gauges). But the hose and small fitting on the end is what you need to check tire pressure with the cast wheel designs of HD. It keeps the measured pressure until you push the release button, again handy because you spend all your focus on pushing that fitting down in a nice straight pattern so you don't loose pressure while checking it.

Has worked well for me for several years.  The one I have was actually a give away 6 or 8 years ago with a minimum purchase.  The next year they started selling them.
jt

Same here....great gauge.  I also have a small HD gauge without the hose, I keep in the saddlebag.  Pretty accurate, IME.