put gears on the bike that fit you perfectly, i.e. the Pinarello, it make sense to make it even more comfortable, especially on the long ride from East to West just to have some pints.
run the Simoncini single speed for now (with chain tensioner) so you can see whether you want to put gears on it or not, it would be a waste of time putting gears on and finding out you didn't like how it ride.
takes notes
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