Joined: Aug 2010
Posts: 12,728
Likes: 2,106
From: Madison, WI
Bikes: 1961 Ideor, 1966 Perfekt 3 Speed AB Hub, 1994 Bridgestone MB-6, 2006 Airnimal Joey, 2009 Thorn Sherpa, 2013 Thorn Nomad MkII, 2015 VO Pass Hunter, 2017 Lynskey Backroad, 2017 Raleigh Gran Prix, 1980s Bianchi Mixte on a trainer. Others are now gone.
If you already have a readout on your heart rate from a GPS or phone or watch, but for some reason want zone too, do some math and tape a little table on your stem that lists heart rates for each zone for your age.