(11-16-2019, 03:38 AM)postoak_imp Wrote: I just installed the FOBO 2. It's pretty slick! I especially like the feature that tells you what your tire pressure would be if the air inside the tire was 70 degrees fahrenheit.

(11-14-2019, 07:36 AM)2017EX_imp Wrote: Back in the day, when I was young and a newbie to motorcycle riding and maintenance ( actually I was a newbie to car maintenance as well ), I noticed that in the winter the tires on my bike lost or leaked tire pressure much more quickly than in the summer. As I gained knowledge and experience with all things motorcycle ( and later car mechanics ), I came to understand what was happening. I found an article that does a good job of explaining the effect of ambient temperature on tire pressure, and have included a link to it.

Many cars these days have TPMS ( tire pressure monitoring system ) as well as some motorcycles. Correct tire pressure is not nearly as critical for a car as it is for a motorcycle, and I use the system in my car as a reminder of when to check the tire pressure on my CB, particularly in winter. The first car I had with TMPS only had a red light on the dash to indicate when any of the tires fell 5 pounds or more below recommended pressure, but now my car shows a diagram of all four wheels and the pressure for each tire. As the article notes, for every temperature change up or down of 10 degrees F, tire pressure correspondingly goes up or down about 1 pound. When the ambient temperature gets colder, the pressure will decrease, when the ambient temperature gets hotter the pressure will increase. Tire pressure will also increase about 1 pound every five minutes for the first 20 minutes a vehicle is driven due to the tires being heated from contact with the road. The TMPS in my car lets me know when to check my bike tires for over inflation as well, when the ambient temperature goes from cold to hot. When I say my cars TMPS lets me know when to check, what I mean is that I can see tire pressure decrease in cold weather, or increase in hot weather on the TMPS wheel diagram.

Tire pressure should always be checked cold, which means that the vehicle, whether motorcycle or car, should not have been driven for at least 4 hours, prior to checking the pressure. I have never been able to figure out why supposedly experienced mechanics at dealerships will check and adjust tire pressure as part of a checklist of items when a car comes in for an oil change, because the tires will not be cold for at least 4 hours from the time the car arrived at the dealership. As a result, whenever my wife or I take a car in for an oil change or other service, it is clearly noted on the work order to leave the tire pressure alone.

For those of us that already know this stuff, it is just a refresher. For newer members that might not know, I hope it is helpful.

https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=73&affiliate=TX3