I haven't seen one of these in person for some time. Apparently, Simplex- made this front derailleur--commonly referred to as the "suicide" front derailleur-- almost to the beginning of the "bike boom" of the early 1970's. When I first started riding distances, as a teenager in the mid-1970's, I actually saw a couple of them. They were ridden by cyclists whose bikes were made before I was born and who most likely started cycling some time before my parents were born.
If you don't like downtube shifters, you'd hate this derailleur because you actually have to bend over enough for your head to touch the top tube of your frame (if it's a diamond-style) in order to turn the lever.
Probably the one good thing about it was that it eliminated the stretch and flex of cables that are used on nearly all shift levers. On the other hand, modern designs have made that flex less of an issue.
Other companies, including Campagnolo, made similar front derailleurs. But it is most associated with the French manufacturer SImplex because they invented it and it was the most prevalent type of front derailleur during the 1940''s and 1950's, when Simplex ruled the derailleur world in much the same way Campagnolo, SunTour and Shimano would in future decades.
If you were riding this "suicide" front derailleur, there would have been a good chance that you were riding another "suicide" part--a stem.
Track racers--particularly in the days of the Six-Day Races-- used these stems, which were usually made of forged steel, because different events called for different riding positions. I've known a few people to ride them, and nobody was hurt from them. That may be due to the fact that they were all highly experienced and trained riders who knew enough to keep the pinch-bolts tight, or had someone else do it for them.
Sometimes shops and teams used "suicide stems" for fitting and positioning purposes. Usually, after the shop's fitter or team's trainer figured out the right position for the rider, the stem would be replaced with a solid one in the proper size.
If you were riding a "suicide stem," you may also have been riding on Cinelli's M-71, a.k.a., "Suicide" pedals.
Introduced in 1971, they are the forerunners of modern clipless pedals. However, they have one distinct disadvantage vis-a-vis Look, Time, Speedplay and SPD's. Those pedals are like modern ski bindings: When you step into them, they click and grab your cleat. To disengage, you turn your heel outward and your foot away from the bike. On the other hand, to get out of the Suicide Pedals, you have to bend over--in a very similar way to which you would have to bend for the "Suicide" front derailleur--and flick a lever on the pedal. I simply can't imagine using these pedals in a peloton and, I believe, nobody ever did.
If you were riding "suicide" pedals, front derailleurs or stems, chances are you weren't riding this item:
During the bike boom, many people bought bikes with dropped bars because they were fashionable. Most, who weren't cycling much beyond the local park (if they cycled at all) found they didn't like riding in a bent-over position. So, brake-maker Dia Compe invented these levers to fit on Dia Compe's road levers, and similar ones like those from Weinmann.
Why were brake extension levers bad? Well, they cut down on how far you could pull a brake lever, which cut down on the amont of leverage you had when braking. Also, the hardware that connected the so-called "safety levers" to the regular levers tended to come loose quickly and often, which led to the risk of those levers coming off altogether when they were used in an emergency.
Do you know of any other bike parts nicknamed "suicide"? We are going to use them to build the velocipedic equivalent of Bruce Springsteen's "Suicide machines"!
