Start by reading
Bicycling Street Smarts: Riding Confidently, Legally and Safely http://www.bikexprt.com/streetsmarts/index.htmStreet Smarts has been adopted by four states (PA, OH, FL, and MO) as their state bicycling manual. The techniques work!
See specifically Chapter 2a, RIDING IN A NARROW LANE.
Be sure that you are visible. Wearing bright clothing (neon yellow) jackets and bright jerseys helps. Don't ride at night or when the weather makes it dark out
if you don't have a headlight and a good reflector and/or taillight.
If the lane is too narrow to share, you won't help the situation by cowering at the edge encouraging motorists to try to squeeze by. Instead, move further left, making it obvious that the lane is too narrow to share. The motorist must then change lanes to pass you. That will leave plenty of space between the mirrors, trailers wider than the car, and the motor home steps they forgot to fold in.
If a motorist honks, that means s/he sees you, and has told you and anyone else around that you have been seen. You should evaluate the honk by onsidering the possiblility that you are being rude, but if you have positioned yourself properly, you don't need to move. You might give a "slow" signal, it says that you know the driver is back there, but it isn't safe to pass.
Enjoy the tunnels! Northern Tier Section 1, Map 4 has two tunnels. See
http://www.dataman.cc/philip/theres_always_another_hill.htm
for more information and a picture.
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