this just came in from Motorrad Elektrik who had the higher output (14.5v) regulator for all Airheads in stock.
Fast service and very knowledgeable too. explained to Rick what I was trying to achieve. He immediately recommended this higher output voltage regulator to better match higher voltage requirements of lithium iron phosphate batteries.
note a higher output voltage regulator is only needed if one is running large loads on charging system. like heated grips, heated jacket, heated gloves, etc. placing a 15-20 amp load on charging system will drop overall volts. which could result in an undercharged li-ion battery.
optimizing a motorcycle charging system for li-ion is brand new territory ... so we'll see soon, how much overall effect changing out to a higher output voltage regulator has.