# Can you adjust derailleur Tension on a Schwinn Sprint/Huret Allivit?



## stationwagonguy (Sep 4, 2020)

So, got a Varsity I'm trying to tune up, and right now I'm slightly stuck- when in the smallest set of cogs, the chain sags a bit. Nothing else terrible going on, and while I realize *no one* should be in the smaller front chainring and the highest rear gear, *someone* is likely to try, so I'd like to eliminate the slack if I can... except I can't figure out how to adjust, well for lack of better term, "B tension" on it... how the deraillieur pulls itself backwards against the dropout.

Is that something adjustible on these at all? Or am I SOL here? I keep googling and I keep coming up empty handed.

Thanks!


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## 1motime (Sep 4, 2020)

Make sure the derailleur is clean with no dried up grease making the spring and parts from moving smoothly.  Well lube with oil and check.  Those springs are know to weaken.  Might have to replace.  Good luck


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## ccdc.1 (Sep 4, 2020)

If I am understanding your question, the Allvit does not provide any 'B tension' provision...the top knuckle is not sprung, like on some Simplex and Suntour and Shimano derailleurs are. The only tension provided is at the bottom knuckle, with the rotational spring at the cage. Of course, there are typically 3-4 detents on the cage that allow for tension adjustment. You may be able to shorten the chain a bit, as long as you can still get up to the large/large cog combination. A longer cage might give you more leeway as well...these were found on Allvits fitted to Super Sports, if I recall. Depending on the year of Varsity, maybe a Simplex TDF, which does have a sprung top bolt and sprung cage...it was used on the 8-speed Varsity models in the early 60s.


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## schwinnbikebobb (Sep 4, 2020)

This might help. Can you rotate the cage around a turn so it puts more tension in the spring.


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## 1motime (Sep 4, 2020)

schwinnbikebobb said:


> This might help. Can you rotate the cage around a turn so it puts more tension in the spring.



In my experience that prevents going to the largest cog.  @ccdc.1 advice about shortening the chain is a good idea for first fix attempt


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## GTs58 (Sep 4, 2020)

There's one issue that I've seen on a multitude of these old lightweights. Someone has messed with the derailleur and the pivot bolt is too tight and the derailleur does not pivot. That will cause chain sag among other things. Does the derailleur pivot nice and easy? Depending on what year the bike is, 64 and 65 have three spring tension lugs on the front of the jockey wheel cage and I believe the 66 & 67 models only have two.

My Varsity is on small small. Note the position of the derailleur and jockey cage.






My Corvette is on the small freewheel sprocket. The chain has the same number of links as my Varsity.





Position of the derailleur when chain is on the large sprocket.


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## juvela (Sep 5, 2020)

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Manufacturer's mounting and adjustment instructions for the Huret Allvit model 1900 rear mech -





Manufacturer's parts drawing for unit -




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## bloo (Sep 5, 2020)

The step that mentions chain cutting and arrow "F" makes absolutely no sense to me. Does it make sense to any of you?


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## GTs58 (Sep 5, 2020)

bloo said:


> The step that mentions chain cutting and arrow "F" makes absolutely no sense to me. Does it make sense to any of you?




Chain cutting is making the chain shorter. The F is indicating the position that the jockey wheel cage loop should be in with relation to the chain. 

I'd like to see a picture of the OP's set up and know if derailleur actually pivots properly on the hanger.


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## bloo (Sep 5, 2020)

GTs58 said:


> Chain cutting is making the chain shorter. The F is indicating the position that the jockey wheel cage loop should be in with relation to the chain.




Thanks. Ya, i got it about the chain cutting. It was the other part, the length of the chain and the resulting angle of the cage. Looks like the end of the cage points exactly to the chain.

The sheet didn't say what sprocket though. In the last step you would be on the largest sprocket, but the graphic shows one sprocket down.

The Corvette pic above looks about like the illustration in the sheet, but it is on the small sprocket. The orange or gold bike is on the large sprocket and the cage is pointing at the sky. I don't mean to be obtuse, but I must be missing something.


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## Eric Amlie (Sep 6, 2020)

I size my chains by having the cage & jockey wheels canted forward & down at about a 45 degree angle when in the big-big combination.
I don't think I've ever had a problem with doing it that way.
Another thing to watch for is the ability of the derailleur body itself being able to pivot back & forth at the attachment to the mounting claw.
I see a lot of pics of these derailleurs where the body is canted back, showing that it's locked up tight at that location.
It can be a finicky adjustment to make to get all the side to side slop out, but still retain the ability to pivot.
There are stops built in that restrict how far the body can pivot both forward and back.


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## stationwagonguy (Sep 6, 2020)

Somehow the forum did not see fit to let me know anyone had responded! GAH. Thank you all!

Trying to get through the questions...

-Varsity is a '68, but I suppose I don't know if the derailleur is the original unit... I know the stem/bars are off a newer Varsity and I got the bike with no wheelset at all.
-Derailleur moves freely, is not bound up on the pivot
-It only has 2 spring adjustment stops on the cage, and it's in the higher tension one already (I think... when facing it, it's the top/left one, if that makes sense)
-I took 2 links out and put them back in already- absolutely refused to go in the largest set of chainrings otherwise.
-GTs58's Varsity's chain is sagging similarly... is this just "how it is"?


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## Eric Amlie (Sep 7, 2020)

I would say the amount of chain sag on GTs58's '64 model looks about normal for the small/small combination.
As mentioned previously, the springs probably lose some tension over the years.
I always store my bikes in the small/small combination to relax the springs and minimize it.


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## Jeff54 (Sep 7, 2020)

Not sure B/C years since I'd rebuild and or restored used Schwinn 10 speeds to sell,  1972  was the last time and so, older than whatever Schwinn made before 72. .  I remember  that same sloppy tension like GT's. When it's like that the shifting is not smooth as should be and causes excessive wear. But, Pretty sure I was able to tighten or wrap the spring (2152) another turn er somtin like that. Another notch maybe. IDK I didn't have any guidance except determination and once I'd figured it out, it might have been a little tricky or tough to get the spring tighter but, solved it. .

I mean, I'd strip every thing including spokes so I could polish rims hubs and nipples like new. Back then you could actually make money doing it. B/C it's been so long, can't remember exactly what or how except, pretty sure it's that spring and a way to increase tension there.


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## Eric Amlie (Sep 7, 2020)

@Jeff54  I think you're right.
It's been a long time since I've torn one of these down to go through it, but I seem to remember when reassembling that you have to wind that spring around to get tension on it, so you might be able to wind it an extra turn.


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## ccdc.1 (Sep 7, 2020)

Just wondering...you mentioned that the wheel set is not original...for reference, what freewheel tooth count is on that wheel set and what is the front chainring tooth combo? Many of the Schwinns of that era had a 14-28 (or less...14-25) rear with a 52/39 front, but the post-1970 Super Sports came with a 14-32 rear...and that was also when Schwinn introduced the Allvit with the longer cage for more chain take-up. Can't tell from the pics, but if your freewheel has a larger cog than 28, the spread is likely too much for the regular cage Allvit.


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