Vice grips are a good all purpose tool. Clamp them to a broken cable to get you home, for example. Headlight and tailight bulbs and the tools to install them. Maybe a length of fuel line with hose clamps, or just a hose clamp. Good zipties they are the modern baling wire. A few first aid supplies, something for burns, mild roadrash, a few motrin, maybe sunblock. How often are you adjusting things versus replacing parts? Most adj. can wait and a debilitating breakdown may well mean serious tools and a trip to a parts store anyway. Think of the repairs you can do without any parts and get those tools gathered. I'm thinking a combo screw driver of good quality, the vice grips, I kinda like the needlenose ones, maybe a 1/4" socketset, if the screwdriver has a drive bit leave the ratchet at home and just use the vise grip to grab the screwdriver better, leave the useless size sockets at home two sized open end wrenches to match the sockets. Just some ideas I had from my experiences years ago. Here is a blast from the past a masterlink for the chain.