Quote Originally Posted by LBTC View Post
DH and I have the ancient Forerunner 301....
We both just strap the unit to the handlebar with the wrist strap - I found it would fall out of the handlebar mount when I used it as a HRM in the house on the trainer so I've never used the mount in the real world.
My 301 snaps very firmly into the handlebar mount, but I really have to push it in hard. Is it possible you weren't getting it in all the way? I always did use the wrist strap as backup, loosely fastened just in case, but it never came off even on some pretty rough roads.