# Axle Thread Damage From Chain Adjusters.



## jimichrome (Aug 6, 2016)

Hello, I removed the rear wheel from my '38 Schwin Pioneer/Whizzer "F" and discovered the chain adjusting bolt ends push against the threaded axle-rod and damaged axle-rod threads.  My question is: What kind of arrangement is supposed to be there to protect the axle threads when tightening chain adjusters? Thank you.


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## keith kodish (Aug 7, 2016)

Don't remember ever seeing anthing about protection for chain adjustors.  Maybe why drop outs with the clamp washers.

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## jimichrome (Aug 8, 2016)

Here's a shot of threads damaged by the chain adjuster bolt. Opposite side is not as bad. This will be a complicated disassembly. 
I'm new to Schwinns and surprised not to find any info regarding this vulnerable adjustment area.  Is there any? Or is there supposed to be something there to protect the threads?
I'll just avoid using the adjusters after damage is repaired.


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## Obi-Wan Schwinnobi (Aug 9, 2016)

I never tighten them that much if at all!!!!  Someone got a little wrench happy it looks like. 

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## frankster41 (Aug 9, 2016)

I think your supposed to loosen the axle nuts before adjusting the chain!!


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## Wheeled Relics (Aug 9, 2016)

Replace the axle is the quickest fix. Chasing the threads with a thread cutting die will fix the damage threads. It looks like someone counter sunk a hole in your axle, on older bikes tens to teens I often see flat spots on front axles for forks but with rear axles for chain tensioners it depends on the geometry of the tensioner in the dropout. In the diagram you posted the chain tensioner contacts the axles bolt, not the axle itself. 

I just realized this is the Schwinn forum and I have no schwinns right now so my apologies if this info is useless


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## jimichrome (Aug 9, 2016)

Thank you everyone for helpful responses.


Wheeled Relics said:


> In the diagram you posted the chain tensioner contacts the axles bolt, not the axle itself.



   Guess I needed a better pic to make my point. The chain tensioner on my ca '38 Schwinn is centered in the slot and when everything is loosely assembled, the only thing stopping the tension bolt(s) when screwed down are the axle threads. Maybe there's a special washer? 
This all started because the Whizzer drive stuff was rubbing and I needed to shift things over.  I'm good to go, Thank you.


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## Obi-Wan Schwinnobi (Aug 9, 2016)

You shouldn't be tightening them to the point it mashes the threads. I don't even use them to center the rim or adjust tension. I just pull the wheel back tell it's centered and I have the appropriate chain tension. Then I snug them up just a c hair. They shouldn't be tightened when you have the axle nuts tightened down either to get the chain tight. Plus the spot that the damaged threads are at doesn't really matter since it's the gap where it sits in the frame drop out and the nut will not be going down that far. If that makes sense. Unless you thread the axle out further to that side it really doesn't matter. Also, what I see here since you said things moved is that you need to get a washer that cuts into the frame and bite. I think it's called a toothed washer or something. If it moved that much then the washer you are using isn't right or you didn't tighten the snot out of the nut...  put more torque on that puppy so it doesn't move... and get that washer...you need one that bites!

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## fattyre (Aug 9, 2016)

Are you sure the drop outs arn't opened up and the tensioner bolt isn't hitting the axle square?  That would lessen the effectiveness of the tensioner and cause it to wedge in.  It could require more force to tension than if it was hitting square therefore damaging the threads.  -if this makes any sense.  

I've never seen any special washers.  That's just the way they are.  Like others have mentioned, minimal force should be used.  

You could just run a die backward to fix threads enough for dis assembly so you don't toast the lock nuts.  Do one side, shift cone & lock nut inward on the other (worst) side and clean threads.

On more than one pre war Schwinns I've owned, the drop outs were all mis aligned and opened up.   Steel is pretty soft on these frames. Aligning drop outs also can help the wheel sit nice and vertical in the frame and not all cock eyed.


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## frankster41 (Aug 9, 2016)

This may have happened if axle nut was loose and from accelerating with the Whizzer motor causing a pulling forward motion of the axle into the adjuster.


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## rustjunkie (Aug 9, 2016)

Might as well check to see if your axle is straight before worrying about the threads. Running the cone or axle nut over that spot with oil on it should fix it up fine anyway, or you could use a little file on it.
Def looks like the fork end is opened up, no longer parallel top to bottom. One of the drawbacks of rear-facing fork ends that was solved by the change to dropouts: lots more metal above the axle, stronger, much less likely to open up over time. As @fattyre said: fork end alignment front and rear is really important, makes the bike ride better and saves bearing surfaces too.


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## Obi-Wan Schwinnobi (Aug 9, 2016)

rustjunkie said:


> Might as well check to see if your axle is straight before worrying about the threads. Running the cone or axle nut over that spot with oil on it should fix it up fine anyway, or you could use a little file on it.
> Def looks like the fork end is opened up, no longer parallel top to bottom. One of the drawbacks of rear-facing fork ends that was solved by the change to dropouts: lots more metal above the axle, stronger, much less likely to open up over time. As @fattyre said: fork end alignment front and rear is really important, makes the bike ride better and saves bearing surfaces too.



I agree. Was going to state that prewar frames blow for whizzers....postwar is best for that

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## bairdco (Aug 10, 2016)

You can use channel locks to carefully squeeze the "drop out" (I know, it's technically called a rear facing fork end) back into shape, and to stop it from spreading back out when you tighten the axle nuts, put a large crescent wrench over the drop out, so it acts like a vice, and tighten up the axle nuts.


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## Critter1 (Oct 12, 2016)

Since this is a thread about chain adjusters... What is the chain adjuster thread pitch on pre war Schwinn's? (such as the one above) Is it a common modern pitch, or is it something that's not used anymore? I need to chase the threads in mine...


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## Critter1 (Oct 13, 2016)

Chain adjuster bolt - thread pitch... anyone??


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## jimichrome (Jan 31, 2017)

Critter1 said:


> Since this is a thread about chain adjusters... What is the chain adjuster thread pitch on pre war Schwinn's? (such as the one above) Is it a common modern pitch, or is it something that's not used anymore? I need to chase the threads in mine...



Sorry for late reply, I've been away from the forum;  The chain adjuster thread pitch on the pre war Schwinn shown above in post #7  is "24".


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## bricycle (Jan 31, 2017)

There are two push to the rear versions. One should press against a thick washer, the other is in middle of drop out and actually pushes against the axle threads. On second style, tighten axle nuts properly and back out adjuster 1/2 turn. Tighten lock nut. Done. Damage only occurs when axle nuts become loose.


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## PCHiggin (Jan 31, 2017)

Get a THREAD FILE @ an Industrial Tool Supply or a good Plumbing Supply house.You can clean that up without recutting the threads with a die and trashing the rest of the axle.


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## PCHiggin (Jan 31, 2017)

P.S. You'll probably use that thread file a lot more as times goes on


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## PCHiggin (Jan 31, 2017)

P.S.S. Dont use the chain adjusters.Get a set of serrated washers,they were used on most bikes,all Schwinns post WWII. Just turn the adjusters in to look like they're being used.Dont run them up to the axle.


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