unable to spread rear stays..why/how.?

[Yardbent]

have acquired an older Peugeot with OLN distance of 120mm

need wheels - lots of new ones available with OLN of 130mm

so built a spreader - out to 140mm - gulp.!
removed 24hours later
OLD returned to 121mm....................... :facepalm:
.


how please..?

 

[Ian Raleigh]

Some interesting reading here matey:

http://sheldonbrown.com/frame-spacing.html

 

[originalshinkicker]

All you are achieving by that is springing the frame. If you left it like that for a week, it would still return to its original size. It's similar to sticking a 130 OLD into a 126 OLD frame; when you take the 130 wheel out, the frame returns to 126.

You need to physically set the new size by 'cold setting'. You need to pull/force each set of stays to its new position. I've done this many times and it can be a bit scary, it is very easy to pull past the limits of the tubing, wrecking the frame. Take it easy with small pulls of the stays, checking your measurements as you go. Because you pull each set of stays individually, you must check you are keeping them central and that the frame stays in track.

 

[Midlife]

Back in my physics days of the 70's what you have done is elastically deformed the steel...... that is you have not really done anything. What you need to do is plastic deformation. You need to be more brutal

Shaun

 

[latman]

i would just squeeze the 130 hubbed wheel in and leave it unset personally

 

[seaneee]

Some interesting reading here matey:

http://sheldonbrown.com/frame-spacing.html

The 2x4 method totally works. Go little by little, but you'll get there. I've done it a few times before I bought a frame spreader.

 

[Yardbent]

i would just squeeze the 130 hubbed wheel in and leave it unset personally

a chicken method - but one i will adopt i think

as levering the frame with a 2x4 .??........knowing my luck - the frame will end up SNUFU

thanks for all the advice everybody......

john

 

[Ian Raleigh]

The plank of wood does work, I watched an old chap do the same but his bit of wood was a cut down bit of scaffolding pipe!

 

[lewisfoto]

Re:

I would only cold set a cheap frame. Although it is not hard, and only a little risky, the biggest drawback is that your dropouts will no longer be aligned properly. A frame builder, or even a really professional bike shop can respace a frame for very little money.

 

[GasPipeWarrior]

Acquire some nice 126mm hub'd rears and ride seven speed. Job's a good un.