I was really hesitant to cut into the frame backbone, especially with just a hand drill. However, you can hem and haw and procrastinate only so long; at some point you have to just have to take the bull by the horns and attempt something, even if it’s wrong. (Unless you’re in Congress.)
I used the two plates bolted together as a template to mark the hole positions in the upper backbone tube.
Ladies and Gentlemen, this portion of this evening’s performance can be found in your programme under the section entitled, “Holy Crap, What Am I Doing?”
Opened the first hole up to 5/8″ with a step drill. Past the point of no return now.
With three more holes drilled, and the inserts in place.
Well, whaddayaknow, it fits. Actually, the right side rear holes were misaligned by about half a millimeter or so, and I had a run a 5/16″ twist bit through the rear hole before the bolt would go in. But, for just freehanding it with a cordless drill, I am very pleased with how well it went.
I was trying to get the shock as far forward as I could to keep the rear suspension height down closer to where it should be. I think I cut it about as close as possible without hitting the frame. I could make a new spring collar on the lathe with a beveled bottom at some point if it turns out to be necessary.
There’s lots more to do. I still need to drill the lower backbone tube and add the two lower mounting points, then strip the area down to bare metal and weld all the bungs into the frame. But at this point the bike can actually stand up on its suspension without any plastic prosthetics. Yay for progress!
