Another vote for bone conducting headphones. They're like driving in your car with the radio on. You hear the music and everything else around you, And unlike riding with speakers,you don't force everyone around you to listen to your music. And like Rides4Beer, I too, can hear my Varia beeping when a car approaches.
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HCFR Cycling Team
Ride Safe ... Ride Hard ... Ride Daily
2017 Colnago C-RS
2012 Colnago Ace
2010 Giant Cypress