To that end, doing a brevet like that SS/FG sounds real tough. Esp. if the course is hilly and you need to moderate your efforts. I'm good for riding my bike for 5-7 hours at a time with some hammering here and there, but after that, I need a warm meal and a shower!
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"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste