Cold Setting A Bike Chainstay

Sidewinder Jerry

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In your picture you have the sprocket outside of the disc. ???

To spread your chain stays, install the althread and turn the nuts out until the desired width in attained, put an extra nut on the outside of the althread to keep it in place. Get a spreader bar clamp and spread the inner part of the stay.
Looks like an awful lot of plastic in that thing. Are you familiar with how to calculate radius in bends so that they don't kink? Some metals can take a tight radius while others may require a wide radius to prevent kinking. Unlike one-shot shoe bends, you have to know how to calculate radiuses to do-hickey bending.

Using a 5° offset in all of the stays would add 1" between the dropouts and keep the dropouts straight instead off at an angle. The 5° offsets would only draw the dropouts 1/16 of an inch closer to the bottom bracket.
 

Chainlube

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Looks like an awful lot of plastic in that thing. Are you familiar with how to calculate radius in bends so that they don't kink? Some metals can take a tight radius while others may require a wide radius to prevent kinking. Unlike one-shot shoe bends, you have to know how to calculate radiuses to do-hickey bending.

Using a 5° offset in all of the stays would add 1" between the dropouts and keep the dropouts straight instead off at an angle. The 5° offsets would only draw the dropouts 1/16 of an inch closer to the bottom bracket.
I just posted that one to show the action, other precautions have to be taken so the frame doesn't kink.
 

Sidewinder Jerry

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I just posted that one to show the action, other precautions have to be taken so the frame doesn't kink.
Yeah, hickey style bending move a slight hair bend move a slight hair back bend, etc until you get the desired degree you're after. If you're a good welder the easiest way would be to cut the whole back end off the bike and use a hickey bender to put an offset in each stay. Then weld the stays back onto the frame.
 

Chainlube

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Yeah, hickey style bending move a slight hair bend move a slight hair back bend, etc until you get the desired degree you're after. If you're a good welder the easiest way would be to cut the whole back end off the bike and use a hickey bender to put an offset in each stay. Then weld the stays back onto the frame.
I used two sticks, that I custom shaped to the desired curve of the stay and used those as feet for my bar clamp, I have the old school bar clamps, they're 3' long and a little cumbersome but it worked.
When I figured out where I wanted the wheel and all its attachments between the stays, basically the width. Then I used the althread to maintain my inner measurement at the drop outs, which was easy because of the flex in the frame. Then I used the bar clamp to spread the front of the stay ever so slightly, maybe 1/4-3/8". Then tighten the althread to bend the stays back to the wheel position. Leave it for awhile or warm it up to get rid of its memory, BAM! wheel, chain, disc fit.
 

FrizzleFried

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Where I am at now with the stay, the chain fits... the disc fits... all is good on that front...

I've ordered a 203mm disc + the bracket to adapt to it.

The front disc is installed and working properly... though still needs some adjusting.

I'm gunna get to the motor this weekend I suspect. I might be able to ride this weekend if I have enough time to work on her.
 

Sidewinder Jerry

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I used two sticks, that I custom shaped to the desired curve of the stay and used those as feet for my bar clamp, I have the old school bar clamps, they're 3' long and a little cumbersome but it worked.
When I figured out where I wanted the wheel and all its attachments between the stays, basically the width. Then I used the althread to maintain my inner measurement at the drop outs, which was easy because of the flex in the frame. Then I used the bar clamp to spread the front of the stay ever so slightly, maybe 1/4-3/8". Then tighten the althread to bend the stays back to the wheel position. Leave it for awhile or warm it up to get rid of its memory, BAM! wheel, chain, disc fit.
You should try the turnbuckle thing.

Here's a good video so if in the future somebody does need to bend you can calculate how to do it without kinking the tubes.

 

DAMIEN1307

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In your picture you have the sprocket outside of the disc. ???

To spread your chain stays, install the althread and turn the nuts out until the desired width in attained, put an extra nut on the outside of the althread to keep it in place. Get a spreader bar clamp and spread the inner part of the stay.
Thats funny...I made one of those already with the addition of parachute cord that I sling onto one side of the frame and reverse the end to press against one side of the frame an the other side and then pull the trigger to spread them now so I am not totally stuck without another set of hands to help...lol.

Haven't had to use it yet, but as always, it's just a matter of time...lol.
 
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