This is the maximum safe bore (106mm) at a stroke of 84mm. This appears to be the maximum stroke that will induce minimal piston rock. Even at the stock strokes the various pistons actually draw somewhat out the bottom of the sleeves. To keep engine height the same, the rods are replaced with some that are shorter by half the stroke increase. To be clear, we start with a XVS1100 crank because there is "less distance to go" in the stroke increase and they are several pounds lighter than 750/920/1000/1100 cranks - less flywheel to skim down for balance. This displacement boost is predicated on such a crank in exchange or three hundred dollars additional. This is conditional as XVS cranks are getting rarer and more expensive.
At BDC the pistons are 13.5mm lower due to the longer stroke and shorter rods. The flyweights will be skimmed down and longer sleeves used to control piston slap. A bonus to be had from shorter rods is the fact that the pistons spend some time motionless at TDC and BDC. This is good for accelleration and gives back some of the top-end that the longer stroke takes away.
Presuming that no crank is coming, this kit will run approximately $5000 with Carrillo rods and oil cooler.