I have an 81 C70, and am having issues with the drive chain. I keep trying to tension the chain correctly, and on the center stand it seems great (about 1/2 inch play up and down with the tensioners pushed as far back as they can go). Once I start riding though it starts making a lot of noise and when I check the chain, sure enough it's laying on the bottom of the chain guard.
I tried breaking a link out of the chain, but then even with the axle all the was forward it's too short to connect. I've noticed that the left tensioner, even adjusted to push the axle as far back as it will go, doesn't move the axle all the way to the back of the frame cut out.
Has anyone else dealt with this issue?
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: