rim offset correct or not

u dont need adjustable. very complex
find out ur spring rate & length
then replace a longer type from honda or other make.
else u research jp website how they mod

less powerful. did u compare gps speed or base on speedo only. now you need less rpm to achieve same speed so fc meter wont be accurate
becos u driven more km than computer calculation. use manual way to kira

flush is cool. just higher chance to scrap ur tyre.
look at both side scrap mark. fender edge & tyre edge