For most dogs, chasing a cyclist is just a game for them, but there are some that are out for blood.
I have found that a well aimed shot of water from my water bottle will stop any dog. I can usually hit them in the eyes at around 20 feet and never even have to break my stride.
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Il faut de l'audace, encore de l'audace, toujours de l'audace
1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1