Just my opinions but here goes:

Kawi front tire pressures are too low, even with the recommended tires on some models. I can't say if that's true for a VN800. If the pressure you are quoting above for the Battlecruise is the pressure listed on the side wall, that is the recommended max pressure for the tire's rated max load. That is not simply a recommended pressure. You are not putting anywhere near the max load on those tires, so using those pressures will over inflate them and wear the centers out very fast.

You need to find the right pressure for your bike plus your normal cargo (that's you, a passenger, saddlebags and contents, etc.). Here is an article with one way to do that: How to Find the Right Tire Pressure | American Sport Touring

I would start out with the front around 34 psi and the rear around 38 - 40 for Battlecruisers as they seem to be pretty beefy tires.

I like the approach in this article of using cold vs hot pressure change to find a good pressure. With excessive heat, the pressure could change a bit more, depending on how cool and how hot the temps are when checking, but it should get you a reasonable tire pressure. If you get very little pressure change, the tire is not flexing enough and you have too high pressure. If the change is large, you have too low pressure and the tire is flexing way too much. Just remember that it may take several rides to get it right.

I have my own method, but it's pretty complicated and requires a tire pressure management system (TPMS).

 

Thanks Greenisbest, for the trouble you went to, appreciated.

 

Some tire mfg publish load vs. inflation pressure tables. Don't know if that's commonly done for MC tires though. Maybe it's published in their technical info online, or maybe they'd send it on request if available.

 

Metzler used to do that. They even had a table of recommended starting pressures base on bike models, but they took that down over 10 years ago. AFAIK, no motorcycle tire mfg does that today.

 

Thanks Whoaru99.

 

I've always used the 10/20% rule, front tire should have a pressure increase of 10%, 20% rear from cold to warm tire pressure. And you'll have to adjust pressures a couple a times per year with weather changes because the tires won't warm up as much in winter as they do in summer. Different tire brands can also warm/cool at different rates. I've read you can get one of those digital temp readers to see the tires temperature, makes it a bit quicker to determine if pressures are good.