After cleaning my carb, the bike starts much, much easier--although I'm not sure the choke was working at all before. However, I still have the hesitation/missing around 30-35, and I'm periodically losing the ability to drive at full throttle, accompanied by an occasional backfire. After a couple minutes of full throttle riding, I lose almost all power until I let off to about 3/4, then the bike acts like it has about 3/4 throttle. A bit later, I can go back to full. I found Mike's guide to adjustment that Chris sent me to, but I haven't done anything with the tabs to allow me to turn past the factory allowed adjustment range yet. The existing range isn't making a difference.
...and that makes me realize that I don't know if I've got that adjustment back to its original position.
1970-73 C70 Honda Service Manual: http://tinyurl.com/6ebwtw
1970-73 C70 Troubleshooting Guide:
http://tinyurl.com/6ebwtw (scroll to sec.7.1 page 101.jpg)
1980-83 C70 Honda Service Manual: http://tinyurl.com/hu42c
1980-81 C70 Troubleshooting Guide:
http://tinyurl.com/hu42c (scroll to sec.18-1 page 170.jpg)
1982-83 C70 Troubleshooting Guide:
http://tinyurl.com/hu42c (scroll to sec. 20-28 page 205.jpg)
1980-81 C70 Maintenance Schedule: http://tinyurl.com/z4zn6
1982-83 C70 Maintenance Schedule: http://tinyurl.com/hw35c
More resources for C70 Passports and Cubs:
http://www.shlaes.com/Vehicles/Scooter.htm
http://www.velodrome.com/HondaC70/HondaC70.html