I'm 210 and I run my rear at about 39lbs on the V. In my opinion it's a trade off. Running a little extra air makes em last and wear better, but softer is stickier. That said, 36 is about as low as I would go intentionally, but I might go up to 40 or 41.
Might want to check your gauge against another one known to read accurately good. I have a gauge that reads 3-4 lbs low. It's kind of like the opposite of what a Kawasaki Speedometer does :-)
Also if they chip-seal roads in your area, that stuff eats tires compared to asphalt I'm in Western NJ and they do it quite a bit here.
'79 Yamaha XS650