I also took a moment to make further preventative measures. I went in with a power drill and hogged out not only the foot peg mounts, but the sub frame mounts as well. Dan fashioned up a couple of plates and welded on some turned down 10mm hardened steel nuts along the backside. These plates would get welded into the factory peg "box", essentially replacing the factory hardware that's got a bad habit of stripping out with bigger, beefier, better hardware. This same treatment was taken to the rear subframe mounts, replacing the existing threaded fittings with 10mm nuts. The upper sub frame mount was drilled clean through, replacing the existing two 8mm bolts with a single hardened 5in bolt. This is a bit more of a common mod done to the KLRs, one that I really recommend.
Sorry for the blurry pics.
I was able to use the factory bracket on the right hand side, the one that the existing water overflow bottle mounts to, as a clearance gauge when placing the secondary radiator. My research led me to believe that the right side radiator out of a KLX was the way to go. Dimensionally, it was fairly close to the stock KLR radiator, but a few inches shorter. This was needed to clear the header. I threaded some bolts through the radiator mounts and stacked several nuts on the other side. With the reservoir bracket in place, I gauged my placement in the dim light with one eye closed and tacked the nuts to the frame. I didn't have a clue at the point how exactly I was going to plumb everything together, but I would get to that when the time came.
I stacked two more nuts on these mounts than what's shown here.
With everything tacked into place, I set about going to town with the grinder stripping away any paint from the welding points. I put a good several hours of welding into this frame while instrumental tunes played in the speakers overhead. I was having WAY too much fun. My sleep schedule was all sorts of fucked at this point. I would wake up late in the morning and be out in the garage from early afternoon well into the wee hours of the morning. I caught some flack for this, but I think Dan got a kick out of not knowing what he would be walking into the next morning before work. He would be going to bed with a bike 90% intact strapped to the bright pink stand, and wake up the next morning with the smell of ozone and burnt metal in the air and a naked frame in the corner.
Again, not the prettiest of welds. I took my time and experimented with my technique. Filling voids first, then laying a bead. Swirling the tip to fill any gaps, or just kind of cross hatching back and forth to spread the material a bit. All and all, I think it came out fairly well. I was nervouse about overheating the thin factory metal and ended up bouncing all over the frame. A two inch weld here, then while that cooled, a few other misc. welds all over. Dan suggested using some filler material on the lower framing gussets, and it worked out fairly well, even if I did have trouble filling the seam and making it look right. I would go through nearly an entire coil of welding wire and half a tank of gas on this job.
Back to the front downtube, I was still undecided how i would reinforce and bridge the gap where I had trimmed off the factory gussets. In the end I just used a beefie chunk of pipe, trimmed into kind of a medalion, to bridge the seam and add some strength. I hope.