I raced with a VX short cage. The Campy boys in the pack in the pack laughed (sometimes literally), and my Superbe-equipped teammates took gentle pity on my "plight". But that thing shifted reliably every time it needed to, and was only a trivial weight difference from the far more unaffordable componentry. Great derailleur - which is what you can say about nearly every rear one made by Maeda (although the plastic cage on the Alpha 2000 on my commuting bike is fixin' to fail soon.)

And this one is a long cage which helps me age ungracefully!

52telecaster You must have won all of the good deal bikes this summer in your area!

It's been a bit ridiculous. Time to let a few go!

The late 70's Super Course is underrated, Surprisingly quick and responsive. I'll have another one one day.

I have a 73 I enjoy but this one feels sportier and more competent. Almost like a competition.

The catalog says the fork and stays are
manganese alloy.

Yeah, it's definitely an entry level racer by the late 70's.

YEP!!! That is an amazing derailleur. My first light weight bike , a Kabuki Diamond Formula came with a corn cob and one of those. I lived on a sail boat and rode that bike(still have it) many many miles , we did not drive a car for over two years and we both worked full time. Salt air and everything was thrown at that thing and when I was out and about I passed all those expensive European bikes up with my Japanese racer! I still have the derailleur but I have since built up the Kabuki with Campagnolo Record .

I raced my first season on a triple and VGT Lux long cage RD. Club races simply as is. Open races I'd set the inside FD limit to double. Rear shifting was excellent. (I ran a 13-19 5-speed and made a short as possible claw hanger from 1/4" aluminum plate.) The Cyclone on my true racing bike the next year felt better but was equaled in the task by that cheap one!

So poor man's 531

I've thought about that (I had an 84 Trek 420 made of Tange Mangaloy)

None of the makers of manganese alloy tubing really tried to position themselves in the same ball park as 531. As I understand Mangaloy and Ishiwata Mangy and Miyata's Mangalight were all classified as carbon/manganese alloys rather than manganese/molybdenum alloys. As such- they're "better" than hi-ten, but "beneath" CrMo.

In Trek terms (*VERY* generally from 70s/early 80s)
200/300- Hi-Ten
400- CMn w/ Hi-Ten stays and fork
500-CrMo
600- 531 frame with CrMo or CMn stays and fork
700- 531 frame with 531 stays and fork
900- Columbus SL/SP

(yes, the 200/300/400 designation kind of went through changes- and the 600 series was CMn early, then CrMo later until 400 series bikes were built like that in 86... but we're talking generalizations here and the rough idea of the weight/prestige of the tubing) (and yes, "better" is in quotes for a reason)

Ty man!

Just the other day I went to buy a 20 dollar tange champion Japanese schwinn super sport for the suntour barcons.. going to use most of the components for a touring bike I'm building for my girlfriend. The guy was so happy I knew a few things about his old bike that he ended up giving me a trek (my gfs size!) 520 frame and a NOS suntour cyclone derailer. Great day. So yes barcons for the win.

I didn't know super sports had tange champion... Great bike!

Any bike that's sporting Suntour barcons is worth at least 45 bucks!

I do think you probably have the lower end helicomatic hubs on that Trek. They have suffered more failures due to small ball bearings and gaps at the cone that allow grit in to help them self destruct. I do have a few of these that are undamaged and seem just fine with light usage and periodic cleaning.
The higher end 700 helicomatics were found on some Treks and have some differences as pointed out by JohnDThompson in this post,
Maillard Helicomatic hub question
The labyrinth seals, bigger ball bearings, and better cones make them much better.
The 6 speed helicomatic freewheels I have work pretty well with Shimano indexed shifters as well.

Those Treks make nice STI, 700c conversions

Yup, 84 Supersport with Tange Champion.

They are just great framesets period. I love 700cs on them with fenders and 35s.... Oh and barcons of course.

Long have I been a fan of Barcon shifters. The Suntour Barcon...


in my mind is much superior to the Campagnolo version...


But the absolute best Barcon that I have ever used are fitted to my Jamaican Bianchi. Indexed and offers a perfect shift, without hunting for that sweet spot, every time...