branko_76 

A couple of years ago I dragged home an abandoned 1975 Schwinn Sprint (with contoured seat-tube). I did so because of its unique design and I never seem to have enough projects...

I decided to start with the rear derailleur because it seemed to be the most difficult component of this bike to restore. This thing is built very well, all steel with plastic pulleys. I also have an older Allvit with steel pulleys. This one weighs 312 grams with the hanger. For comparison, the Campy N.R. weighed in at 206 grams (no hanger).

Tools needed to disassemble it are as follows:

6mm allen wrench
8mm combo (or socket) wrench (2 needed)
9mm combo (or socket) wrench
13mm cone wrenches (2 needed)
14mm socket wrench (open end will work but socket is better)
sturdy vise

As dirty as this thing was, I did not have to pre-soak it in solvent to loosen any of the bolts. The only rust was on the chrome plating. Once disassembled, I cleaned all of the parts with a soft wire wheel attached to my Shopsmith 10ER which was set to the lowest speed for safety reasons. ALWAYS WEAR SAFETY GOGGLES

Most of the bolts are threaded to the body. The nuts are locknuts, so they should be removed before attempting to remove the bolts to avoid stripping the threads.

When assembling the parts, the bolts should be left slightly loose untill final adjustments are made. This is best done with the hanger mounted in a vise and then testing the movement of the spring action while tightening the bolts and lock-nuts. Everything should be as tight as possible without hindering the "in and out" and "back and forth" movement of the derailleur.

A slide-show of the process to follow...

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

branko_76 

(15) 1/8" Bearings Each Pulley



Grease to hold bearings in place

branko_76 

Velo Mule

Thanks for posting this branko_76 . Nice job with documenting this rebuild. It is neat that on this derailleur that the link pins are shoulder screws and can be removed.

I am on the fence about the Huret derailleur on my Continental whether I should use it or not. I'll probably try it out, at least to start out. But there will be a tremendous temptation to use a Shimano or Suntour rear derailleur. Kudos to you for keeping it original and restoring your rear derailleur.

On another topic, it looks like you have an old maple top workbench. I love these workbenches.

branko_76 

OOPS....

branko_76 

Thank you. I really like these old all steel Alvitt and Huret Derailleurs.

That bench is 9 feet long and 3 inches thick, a buddy of mine helped me drag it down to the basement, hope I never have to move it again

Velo Mule

You have inspired me to give my Huret/Schwinn GT510 derailleur a more serious try. Mine has riveted link pins and a few minor differences from your Allvit. I had a Huret on my first 10 speed, a Astra. Probably 1974 or so.

branko_76 

a litle "tri-flow" or similar lube in those joints after a thorough cleaning should keep it snappy

dddd

The Allvit is cool with it's knee-action design. These can at the limit be modded for use on a standard 6s freewheel, but the need to do this emphasizes just how old that this design is (introduced in the late 1950's).

I think that few people have ridden a good bike with a well-tuned shifter, cable and Allvit derailer all together on the same bike. It works really well within it's allowable range of cog size and number of cogs. Like certain other old bike parts, Allvits were used on the widest imaginable quality range of bikes, from Varsities to exquisite constructeur models.
Here's one mounted on a Schwinn Supersport, under a 6s freewheel:

bulgie 

Thank you branko_76 for the excellent photo set and write-up.

The long-cage Allvit on my '73 Super Sport wasn't great. It worked, but it took high lever effort, and it was "reluctant" to shift all the way down to the small cog. OK it pretty much never shifted into High. It was bad when I first got the bike in the early '80s -- then I experimented with decades of benign neglect, to see if that would fix it. No such luck, it got worse.

When I disassembled it (6 years ago), I found three of the parallelogram parts were bent, and the pivots had no lube, unless road grit counts. Not the derailer's fault; this bike was abused. Amazing it worked as well as it did. (Try straightening a Delrin Simplex sometime... lol )

Cleaned and straightened each part, then assembled with light grease in the pivots, and all pivots adjusted just right. (Nice that they're adjustable, but the downside is you have to adjust them. Duh.)

The bottom (lowest) arm, which is cast bronze and has the cable anchor and inward-limit screw built into it, has a steel bushing that runs inside of it. The steel bushing is supposed to be fixed (stationary), pinched between the downward projections of the main body. Then the bronze piece is supposed to pivot on that bushing. But mine were corroded together, to where the bronze part couldn't move relative to the steel part. I tapped it out with a punch, sanded it down and polished it to where it moved freely inside the bronze part, then reassembled with light grease on all the bearing surfaces.

Oh and this might be the most important part: I bent the parallelogram spring, in the direction that increased the preload, to make it want to shift to High with more alacrity, authority and ability! (Speaking of High...)

Now I really like the way it shifts. In the 6 years since I overhauled it, it's been ridden several times a week on errands, grocery-getter and beer runs duty, and the occasional picnic, w/some gravel and singletrack thrown in. A fair bit of that in the rain, so the bike is once again covered in grit&grime. But the mech still feels fine. Maybe in a few more years I'll give it some more lube at the pivots -- maybe on the 10-year anniversary of the overhaul. Other than that, total neglect.

I am happy to have put $200 worth of labor into a $5 derailleur. Seriously! You can't put a dollar value on that feeling that comes from keeping a piece of garbage out of the landfill. Hmm, maybe I could phrase that better.

Mark B in Seattle

merziac

Nope, you got it right, the ability to do the right thing is priceless. So many will tell you its not worth it or the time, really, when I save a part that may or may not present itself when and how I need it, I save a lot more than $$$, time and resources, it pays dividends far down the road being able to fix, save, troubleshoot and become better at doing so, again priceless.

KenNC

Really enjoyed this. I derive as much pleasure from restoring the little bits, as I do from a re-assembling the complete bike. Of course then the little bits need to go somewhere....
Have an Allvit in the queue for restore. My earliest real bike, back around 72, came with an Allvit, but that bike was stolen within a year. Fond memories so really need to give the Allvit a try!

branko_76 

branko_76 

You're a trooper !

I spent a good part of my Saturday with this derailleur. I've got about 3 or four more that could use the same treatment. The next ones should take less time.