Whats the best bicycle chain thickness?

There are a lot of chain types and standards that have been made for bicycles over the years. As time goes by chains are getting thinner and thinner in order to accommodate higher sprocket ranges on the rear cassette. However not all chains are the same. So which chain should you look for on a bicycle? When bicycles were invented in the 1800's there was a lack of standardization which led to a proliferation of various incompatible chain standards. Eventually one standard became common, especially on the track circuit, the block-chain used on skip tooth cranks. It was thought to be stronger than the average chain and up to the torque delivered on the track so it persisted as a track or fixed gear standard up until WWII. In general as shifting technology and manufacturing processes were not that great in the beginning most bicycles continued to be manufactured as single speeds (with a few exceptions). Endurance racing at competitive turn of the century events such as the new Tour de France and renowned Giro de Italia necessitated a new way. Riders were tired of being forced to use flip-flop hubs with one gear on each side. In order to overcome significant terrain elevation and to keep the competitive advantage without stopping to flip the wheel with wrenches new shifting levers were adopted. These varied mechanisms such as the 1947 Campagnolo Cambia Corsa included two long right-upper-chainstay levers for forcing the rear stays apart in order to change gearing and tension - all while in motion! It was at this point that the arms race for more gears started, necessitating smaller chain widths to fit in between the numerous gears. By 1970s bicycles were getting in tho the 5-speed range and the combination of the 1973 oil crisis coupled with early advancement in computer-aided engineering created a golden renaissance in bicycle innovation. New derailleurs came about moving the industry from the Simplex Patent 2-dimensional models to the more reliable and accurate slant parallelogram patented by SunTour. Bicycles quickly moved from 5 to 7 speeds and the rear drop spread was increased accordingly from a 122mm standard to a 126mm by the 1980s. It became increasingly apparent that the rear drops and freewheel widths could not grow in width infinitely so after the 8-speed chain things had to get thinner. Not only did the material need to get thinner to fit in between thinner sprockets but also the way these chains worked had to be re-engineered with concepts like one-directional disposable pins. Another main issue at that time was the new index shifting technology that grew out of the Shimano - SunTour rivalry to replace decades-old friction shifting. This technology while quite finicky at the time also had issues with compatibility between different speed standards. And for the first time systems became less cross-compatible with each new successive marketing standard announced. This both allowed corporations to utilize their patent portfolios to make better drivetrains than was ever possible prior and also meant that for the home tinkerer drivetrains became a compatibility minefield between different years/brands. You can still buy modern 8-speed chains mass-manufactured from reputable industry leaders such as Shimano and SRAM which are compatible with 5-6-7sp systems. These chains are ticker and less prone to breakage through torque and regular wear. Their pins are thick enough that they do not necessitate the purchase of individual replacements with every modification and most come standard with master links for easy disassembly without having to even use a chainbreaker. Most importantly these chains are still used on some new bicycles and are compatible with most everything you can find on the vintage bicycle market from between 1970-1987. As a casual rider you really dont need the cutting edge tech to win by seconds, and you also should not feel like you have to pay a premium for it. If youre looking for an affordable bicycle to ride with a strong chain a 7-8 speed bicycle is the way to go. And what is going to make more of a difference is how how fit you, the engine, are at pedaling your machine and not how many gears it has. (all that being said if you find a bicycle that is following a newer standard at a great price dont let me stop you. The chain should obviously not be the deciding factor if you find a new bicycle at a fraction of the cost it retails for on the Sprocket app) 7