My solution cost about $1. I buy 5/16-18" or 8mm hex coupling nuts, grind every other hex point, install a protective bolt and drive them into the bar end with a hammer. Once in, there not coming out. I also use a 3/16" long flange spacer on the throttle side. http://www.mcmaster.com/#90264a445/=1rkpct http://www.mcmaster.com/#93020a781/=1rkq3b
Brilliant. Too bad for me, I already wasted a good hour of my life drilling out the center to 1/2 inch for my Acerbis Rally Pros.
Lots of solutions for that type of install... http://www.mcmaster.com/#insert-nuts/=1s1wn5 http://www.mcmaster.com/#insert-nuts/=1s1x0l
If my wife wants to entertain me for an hour, she puts me in front of the computer and pulls up the McMaster-Carr website.
Mcmaster Carr has come to my rescue countless times. I was restoring a '69 Husky and the only thing I had for the air cleaner assembly was the air horn. I was able to source all the rest of the components including the the filter cover from McMaster Carr.
