The popular harley turbo kits are Aerochargers. A turbo that doesn't need it's own oil feed but it works with some oil mist technology of their own. Can also be installed in any angle thay say. Don't know how long life that is or anything but it seems it works well on the models they make it for.
A single carb
bike is pretty simple to turbocharge, and any motorcycle can handle 0,5bar boost except for the
stock clutch that might start to slip.
I counted that this kind of set would cost about 1000-2000euros depending on accessories like intercooler and oil cooler etc that are not a must. As long as you can do most of the fabricating your self.
I could never go back to stock now. Not that I didn't love the bike already, but the torque and powerband make the bike feel a ton lighter and effortless to drive
Not to mention the beat up of smaller sporty bikes and mid range sport cars that think they could take on a lazy big cruiser
I've never driven a R* with high comp pistons or any other power ups, but would love to see how they behave compared to my bike