This was a easy " bolt on " moidification. vented disk from a Vt600 88 -90 or INTRUDER 750 87-91 Mine is an aftermarked one.
To sharpen it even more maybe softer brake pads
Now i have to eksperiment with spacers in the forks to get the proper static Zag, so i can get the full benefit from the incrased brake performance.