That bash guard (the curved surround part) appears bent outward.
Other than that, the SHIMANO EAGLE is quite a very good basic rear derailleur.
It is designed to be heavy and indestructible. Shimano took the input from Schwinn engineers who had insisted that a protective bashguard in the form of what it was on the GT-100 that was built for Schwinn in 1969 for introduction on the 1970 Suburban five speeds and 1970 Collegiates.
Shimano realized that the protective bashguard that Schwinn engineering insisted upon did have real world benefits as Schwinn knew it did. Shimano was smart enough to essentially say, okay, we learned something else, so lets now make one of our own with the incorporation of a massive bash guard. Thus, the EAGLE emerged, essentially a LARK / SKYLARK with incorporated suggestions that Schwinn engineers wanted in theirs (GT-100) of the cable saver feature and a protective bashguard.
Heck yes, some people make fun of the excess weight that the bashguard adds to the rear derailleur but you've got to remember this great rear derailleur was destined for bicycles that were gonna be owned by people previously unfamiliar with anything but basic cruiser coaster brake bikes that you could essentially treat like airport baggage handlers, or fed ex & ups delivery people.
The benefit of it taking one helluva beating and rough treatment and staying in perfect operational tuning was priceless.
So big deal if it weighed 100 grams or so more than the lightest rear derailleur of that time (~Campagnolo~)did. So what, its like you're carrying an extra nickel and an extra quarter in your pocket, you're not racing in France in the Tour de France.
Though that EAGLE rear derailleur was a staple on many $79 lowest line department store bikes of the early seventies, it remains a far superior rear derailleur in operational function to anything at any price point that Campagnolo, Simplex, or Huret ever produced in the Seventies. There are a few slightly different editions of the EAGLE rear derailleur as evidenced by how EAGLE is written there and slight differences in bashguard variations.
Sheldon Brown has extremely high praise for the Shimano EAGLE. Perhaps, you may wish to go and see what he wrote.
The Disc Brake never gained acceptance in the Seventies. You didn't need it. You certainly didn't want it on the rear wheel of a ten speed. It was a sales-marketing ploy to say to idiots that didn't know any better, "That You Should Buy Our Bike Because It Has Disc Brakes." J.C. PENNEY's tried for a bunch of years to feature DISC BRAKES on ten speeds during the SEVENTIES and initially some idiots bought into the premise that DISCS must be better only to find out that oh how dumb could I have been because I now realize that 90% of braking on a Ten Speed is done with the Front Brakes, and this DiSC Thing at the Rear is beyond stupid!
Schwinn had disc brakes on one of those decked out high rise handlebar little boys 20" wheeled bikes by 1972. It made a heck of a lot more sense on something that was ordinarily stopped via the rear coaster brake skidding the rear wheel. Chain slip offs or the internal coaster brake getting overheated goin' down repeated long downhill descents and stops were now not as much of a factor, in theory anyway on the 20" bike(s) that had those. They did work very well if set up so adjustment was as it should be. They were not user friendly in that you had to take it in to service it and/or to obtain parts if you were going to DIY service by following GLENN'S MANUAL step by step how to.
Practically, they public didn't want the added expense and complexity, even though no question that stopping power was far superior, but having discs on the back of a ten speed just made zero sense. The significant added weight and location at the rear wheel essentially made DISC brakes of that era, practically UNUSEABLE for a ten speed. Now for a coaster type application they should have been a winner, but the public never saw it that way, the added cost and complexity turned them off to the idea, since weight would not have been the factor on those types of bicycles. Market penetration and acceptance was very low. The idea was dropped for decades.
Huffy's get laughed at by too many people. People forget that the rear derailleurs as seen on those low buck Huffy's and other Murray's Free Spirits for SEARS, Columbia's and the imported Japanese-Korean built ALL-PRO bikes for K-mart, feature far better rear derailleurs than the English & European bikes, like the Raleighs & Peugeots and the even much more expensive FRENCH, ITALIAN, BELGIAN, & ENGLISH bikes that cost even as much as five times what the Huffy's, Murray's, & Columbia's did in the early Seventies bike boom. The Shimano rear derailleurs were easily at least twice as good as anything Europe ever produced. They didn't break easily and they stayed in tune and reliably shifted every single time. Shimano freewheels were also far better engineered and advanced than anything European made was from 1970 onwards. Maeda Suntour also had superior freewheels and rear derailleurs to all of what the Europeans had to offer from 1970 onwards. The fact that the good quality basic Japanese stuff, that appeared on thousands upon thousands of low-buck dept store bikes in the Seventies, was far superior to even the top of the line European rear derailleurs and freewheels of the early Seventies era still irks a great many classic steel European bike afficionados to this day. As much as they love Campy and the lovely script and looks of the Campagnolo rear derailleurs, they hate that their beloved Campy is second rate to even the most inexpensive low level Shimano and Maeda Suntour rear derailleurs from 1968 and beyond. Shimano went on to rule the world. Campagnolo, Huret, and Simplex were wiped out by 1977 as far as rear derailleur acceptance goes. Shimano and Maeda SUN TOUR were just simply that much better in engineering execution and quality control. Heck, you would not be wrong if you would assert that, oh well , all Shimano & SUNTOUR did was come in during the sixties and comingle and copy the best European designs and refine them. Yes they did. The Japanese took it to another level, still unmatched today, as Shimano is still on top today, some 55 years later.
