Same time interval no matter the speed. That's the whole point. It means the faster you are going the further back you have to be.
Edit, problem is 20 mph is about 9m/s so the right time for AG is somewhere around 1.33 seconds (debatable). I can imagine a little button you could buy for like $5 that you put on your extension. You press it when the guy in front of you passes something. Then 1.33 seconds later it beeps. If you've passed that thing, you're too close.
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Ed O'Malley
www.VeloVetta.com
Founder of VeloVetta Cycling Shoes
Instagram • Facebook
Edit, problem is 20 mph is about 9m/s so the right time for AG is somewhere around 1.33 seconds (debatable). I can imagine a little button you could buy for like $5 that you put on your extension. You press it when the guy in front of you passes something. Then 1.33 seconds later it beeps. If you've passed that thing, you're too close.
-------------
Ed O'Malley
www.VeloVetta.com
Founder of VeloVetta Cycling Shoes
Instagram • Facebook