Do all 70's have a chain tensioner? My chain is real loose, but don't see one. Where would it be? Also, how to remove the brake drum to inspect the brakes. I think it's a 1978 or 1980 model. Gas tank has honda in yellow and atc 70 under it. Numbers on fork neck is TB03-2003422. Clay

There should be some sort of chain guide/tensioner:
http://www.glamisdunes.com/invision/upload...66174_thumb.jpg
Hope that link works...

I found it, got it tightened. Thanks. Now I can't get the brake hub off to check the brakes.

The brake drum should just slide off. Make sure after you take off the wheel and the spacer that holds the drum in place that you relieve the tension on the brake lever at the rear of the bike...

Relieved tension from brake, no avail. Heated it up with Mapp torch and pried with screwdrivers, not budging. Should I try to heat it up with a cutting torch and pry more?

Try out this site for atc70 stuff http://autos.groups.yahoo.com/group/ATC70/

Relieved tension from brake, no avail. Heated it up with Mapp torch and pried with screwdrivers, not budging. Should I try to heat it up with a cutting torch and pry more?

Make it easier just remove the rear axle, i will bet you the rear break drum will come off with the axle..