TireGard tire pressure monitor, cost about $150. Have had it on my bike for seven years now.

 

Making it easy to add air to tires and accurate tire gauges are not in the interest of HD or any tire manufacturer. During bike week a few yrs ago a Dunlop Rep gave me a handful of tire gauges. High to low they varied about 20#s. All measured to the low side. If your tire gauge is not accurate or consistent regular testing is a waste of time for the most part. A $5.00 tire gauge is most likely not going to be as accurate as a more expensive one.
My '09 RGU with the Knuckles wheels was such a pain in the *** to check tire pressures that I bought a set of Street Glide wheels. Problem solved. Think about it, some of the tire wear problems may be due to improper tire pressures. Hope this helps.

 

Yep. Me too. And no, I don't lose any pressure when I unscrew it.

 

same here