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Discussion Starter · #1 ·
Has anyone compared the reading on the bike to a reading on a good TP gauge? If my bike shows cold TP as 42 my really good gauge will show 3 to 4 pounds under. Same when the tires are warm. I have decided to not trust the bikes reading and go with the gauge.
 

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Always go with the gauge. On my GSA, every once in a while, the TPMS shows I'm exceeding the tire limit and at 79 psi. Use the gauge.
 

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You know,
It kind-a amazes me that, with a bike so well thought out, so well engineered, with such high quality control in manufacturing, that there is some Poor operational components or parts. So far, at least accoring to the folks who've answered on this post/thread, the majority say to use an independent tire pressure gauge vs relying on the accuracy of a tire pressure monitor system in a $30,000 motorcycle. And that also goes for the fact that about 90+% of the K1600 riders think the on board Blue-tooth and com systems are also JUNK.

I know and realize that air pressure, in ANY gauge is always a sort of crap-shoot. People have multiple air gauges at home and can get multiple readings on the same tire. How do we know the tire pressure monitor system is not totally accurate and, any other off-the-shelf air gauge is? Who's to say the bikes system is not dead on? And to take that one step further, "Dead on" with WHAT? Does it matter if you pay $10 or $80 for an air gauge? And, does it matter if it's standard analog or, digital? I think people think that, just because an air gauge is digital, it HAS to be accurate. Who says? What is there out there to compare to?

Torque wrenches are periodically calibrated to bring them within a very tight spec of accuracy. I don't think I've ever seen any info on calibrating an air pressure gauge, to make it accurate. The pit crews for Indy cars, I'm assuming, use fairly accurate tire pressure gauges. After all, they're working on cars that do well over 200 mph. If they claim their gauges are super accurate, what's different about theirs, then the ones we can purchase or, the tire pressure monitor system on the K-bike?
Scott
 

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Tire pressure is one of those things I choose not to obsess over.
The K1600 has a temperature compensated TPMS, which means that it always shows the pressure that a good external gauge would read, IF the tire temperature were 65 degrees F.
My Connie didn't have the temp compensation, so it displayed the actual tire pressure at the current tire temperature. It wasn't unusual to see 39 psi as I rolled out of the garage, and 42 psi a few miles later. Unless I'm willing to pull over and adjust the tire pressure every few miles, I've got to accept that close to 10% change in real-live tire pressure as negligible. This will probably kick off a whoop-de-doo from the tire scientists on the forum, but I'm guessing that tire pressure really isn't a problem until you're close to 10 PSI (not percent) off of the recommended pressure.
I check the TPMS on every ride, and when I see less than 40 psi at the start of the ride, I add a few pounds when I get home. If I ever saw a significant disagreement between the pressure gauge on my compressor chuck and the TPMS, I'd get a third opinion, but so far that hasn't happened.
When it comes down to it, I rely on the bike's TPMS to tell me when I need to warm up the compressor, and when to quickly pull to the shoulder if I pick up a nail while riding. The accuracy I've observed suits those expectations.
 

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You know,
It kind-a amazes me that, with a bike so well thought out, so well engineered, with such high quality control in manufacturing, that there is some Poor operational components or parts. So far, at least accoring to the folks who've answered on this post/thread, the majority say to use an independent tire pressure gauge vs relying on the accuracy of a tire pressure monitor system in a $30,000 motorcycle. And that also goes for the fact that about 90+% of the K1600 riders think the on board Blue-tooth and com systems are also JUNK.

I know and realize that air pressure, in ANY gauge is always a sort of crap-shoot. People have multiple air gauges at home and can get multiple readings on the same tire. How do we know the tire pressure monitor system is not totally accurate and, any other off-the-shelf air gauge is? Who's to say the bikes system is not dead on? And to take that one step further, "Dead on" with WHAT? Does it matter if you pay $10 or $80 for an air gauge? And, does it matter if it's standard analog or, digital? I think people think that, just because an air gauge is digital, it HAS to be accurate. Who says? What is there out there to compare to?

Torque wrenches are periodically calibrated to bring them within a very tight spec of accuracy. I don't think I've ever seen any info on calibrating an air pressure gauge, to make it accurate. The pit crews for Indy cars, I'm assuming, use fairly accurate tire pressure gauges. After all, they're working on cars that do well over 200 mph. If they claim their gauges are super accurate, what's different about theirs, then the ones we can purchase or, the tire pressure monitor system on the K-bike?
Scott
The "problem" is not that the TPMS is junk. The problem is that ridiers do not understand what the little number on the dash is telling them. If they took the time to actually read the rider's manual, they would very quickly come to understand why there is a difference between what the number on the dash is telling them and what their eleventy-billion dollar digital tire gauge is telling them (unless the temperature of the air inside the tire is exactly 68°F (20°C).
 

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I have reasonably priced (about $20), yet accurate, analog dial tire gauge. I also have a very cheap pencil type gauge that is within 1 psi of the round dial analog gauge. Those two are the first and third opinion with the TPMS being an active monitoring tool.
now how do I know my dial type analog gauge is accurate? I have compared it to a an aircraft tire fill valve/gauge tool that is certified and calibrated accurate.
Nothing is perfect, but this method is close enough.
PS the pencil gauge is super convenient to carry on the bike.
 

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PS the pencil gauge is super convenient to carry on the bike.
My 3" Slime gauge works great, fits easily in the fairing pocket, and as I recall, did not cost me a dime. 😁
 

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Trust the bike reading. Your garage gauge is not temperature compensated so if you are using it above or below 68 F it's not accurate. The bikes TPMS is temp compensated.
 

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2021 K1600B Kalamatta
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This cracks me up, I had posted a similar question in regards to when does the TPMS Warning actually come on and got no responses. And I only asked this because I like most use a gauge before I ride and TPMS is more for insurance. However I got the warning on the Garmin but nothing on the bike dash itself and my front tire had dropped to 33psi. They were both checked cold in the garage and showed 42 each and I had only ridden about a couple hundred miles and was on my way home. Temps had dropped into the low 40's compared to when I left. But TPMS still showed my rear tire at 42 and front at 33. So when I took it in for my tire change I asked when should the light come on. I was told its the same system as in the RT's and should come on between 34-36psi.
 

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The "problem" is not that the TPMS is junk. The problem is that ridiers do not understand what the little number on the dash is telling them. If they took the time to actually read the rider's manual, they would very quickly come to understand why there is a difference between what the number on the dash is telling them and what their eleventy-billion dollar digital tire gauge is telling them (unless the temperature of the air inside the tire is exactly 68°F (20°C).
Except that it doesn't actually work like it says it does. When it is 68°F, it still doesn't match a known good gauge. They simply inaccurate and inconsistently so. My built in TPMS shifts 2-3 PSI at times while I'm riding. If is doing the temperature compensation correctly, that makes no sense. It shouldn't be moving 2-3 PSI as the tire warms up.
 

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Trust the bike reading. Your garage gauge is not temperature compensated so if you are using it above or below 68 F it's not accurate. The bikes TPMS is temp compensated.
The change should be 1 PSI for every 10 degrees....and easy number to adjust for. So, if you're between 60 and 80, the most it should be off would be 1 PSI....close enough.
 

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Discussion Starter · #16 ·
Tire pressure is one of those things I choose not to obsess over.
The K1600 has a temperature compensated TPMS, which means that it always shows the pressure that a good external gauge would read, IF the tire temperature were 65 degrees F.
My Connie didn't have the temp compensation, so it displayed the actual tire pressure at the current tire temperature. It wasn't unusual to see 39 psi as I rolled out of the garage, and 42 psi a few miles later. Unless I'm willing to pull over and adjust the tire pressure every few miles, I've got to accept that close to 10% change in real-live tire pressure as negligible. This will probably kick off a whoop-de-doo from the tire scientists on the forum, but I'm guessing that tire pressure really isn't a problem until you're close to 10 PSI (not percent) off of the recommended pressure.
I check the TPMS on every ride, and when I see less than 40 psi at the start of the ride, I add a few pounds when I get home. If I ever saw a significant disagreement between the pressure gauge on my compressor chuck and the TPMS, I'd get a third opinion, but so far that hasn't happened.
When it comes down to it, I rely on the bike's TPMS to tell me when I need to warm up the compressor, and when to quickly pull to the shoulder if I pick up a nail while riding. The accuracy I've observed suits those expectations.
I agree 100% with your post. I don't fret over a few pounds of pressure. I also didn't know the TPMS was temp sensitive, which answers a few of my questions. I live in the High Desert of Kalifornistan where it gets down below 30 during parts of the winter. Three hours later it will be 70. Thanks for the great info!
 

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Has anyone compared the reading on the bike to a reading on a good TP gauge? If my bike shows cold TP as 42 my really good gauge will show 3 to 4 pounds under. Same when the tires are warm. I have decided to not trust the bikes reading and go with the gauge.
Mine does the same thing.
 

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The main thing I now know and admire about the TPMS sensors are they 1) have alerted me when I had a small puncture, giving me enough time to plan, and 2) alerted me immediately in a blowout situation in the Utah boonies near Diamond Fork hot springs when an arrowhead sized rock went right thru my rear tire carcase. No roadside fix for that one; called MOA towing and free tire replacement.
 

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Has anyone compared the reading on the bike to a reading on a good TP gauge? If my bike shows cold TP as 42 my really good gauge will show 3 to 4 pounds under. Same when the tires are warm. I have decided to not trust the bikes reading and go with the gauge.
same with me
 
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