This is one of my favourite adverts.
I can really feel for the guy in the stripy shirt, riding his nasty French bike with its nasty, slippery, narrow diameter, steel handlebars badly wrapped in nasty, shiny, slippery, plastic handlebar tape and equipped with nasty, plastic, Mafac brake levers that were guaranteed to work loose and rotate alarmingly at a critical moment. I’ll bet the saddle on his bike is a nasty, unnecessarily narrow, rock-hard slab of unpadded, unergonomic, cheap plastic. It’s enough to make a mountain out of the smallest molehill.
Unfortunately upgrading to a SunTour drive chain will not help him with any of this. What he really needs is a better bike - and the fairly decent looking, SunTour equipped, Fuji on the second page would certainly fit the bill.
Browse associated derailleurs.