I did a set of GSXR triples I gotta send back out to JackstandJohnny here on CF, I have a 4 flute mill bit that does perfect 12mm plunge cuts on triples all day long. I used to do the hand drill and then drill press methods but ended up liking the results of the mill most of anything.
In my opinion, stock up on good tools
and spend the few bucks to ship the stuff to a machinist for properly indexed and drilled holes.
JJ's triple machined for backing plates to cover the skeletal structure under it. Which by the way can make a hand drill have fits staying center on, even the cheap drill presses have some issue holding a triple solid if the bit heats up and starts to clog.
The riser was kinda twisted on the one closest to the camera, there is no overhang from the risers to the triples. It is absolutely as wide as you can go on the triples and still fit the bars mounting area into them properly. You ain't getting that precision without some experience and good tools.
