Bumping an old thread.
I just tried installing my Motorcycle Larry handlebar risers that I ordered last season and didn't get to ride much. I, too, believed what they said when they said that there was enough slack in the cables/lines for a 1" riser, but it's not true. Both the brake line and the clutch cable were too tight. I could have adjusted the brake line and made it work, I think. I took off the little clamp that holds the brake line to the triple clamp, and there is an extra rubber sleeve around the line (for abrasion protection, it seems), that if I had worked at it, could have been moved down and then re-clamped with enough slack for the 1" rise. But given that the clutch cable was too taught at the lever/adjuster, too, I decided to put the stock parts back on and came in to do this research on this forum.
It looks like a few folks have got it to work by rotating the bars a bit, but I like the stock orientation, just wanted to relocate it upwards. In another thread, someone posted that the Honda Transalp clutch cable (Honda part# 22870-MAB-620) is 2" longer, and that looks to be the ticket, for ~$15.