Motorcycles (when riding two-abreast on en echelon). My experience the bike on the outside won't move over an inch for a bicycle. My other problem is pickups (mainly) with large/aggressive tread tires. They are very hard on my hearing. I would actually love to have some sort of hearing protection that attenuates that tire noise but still allows you to hear other stuff. The other PITA is 2-stroke mopeds that stink to high heaven after going past you. I have a route with a 4 mile hill about 6% ave and some big guys on those mopeds those things are full throttle. Or a pack of kids on modified ones that scream. (But they like to pull wheelies and what-not which is entertaining.)
scott s.
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