Bent triangle
- Thread starter ILoveMyElectra209
- Start date
Help Support Rat Rod Bikes Bicycle Forum:
three steps.
First is the "string method" for checking the alignment and rear drop out width.
Second is getting the dropouts parallel to each other.
Third is the chain line.
Everything you need is at the Sheldon Brown page on frame alignment. Pictures included.
https://www.sheldonbrown.com/frame-spacing.html
These cheap gas pipe frames are the easiest to realign. Some get (oopsie) bent when someone drives the car in to the garage and squeezes the bike up against the wall.
Aluminum and carbon fiber frames are not straighten-able without destroying them for good. Cromo frames are so much stronger it's hard to cold set them.
I respace and align several frames every year. Some due to damage, mostly because I do a lot of single speed conversions on derailleur bikes. . Respacing a frame to fit a hub vs adding spacers to an axle to fit a particular frame. Just depends on the frame construction & hub. Most single speed hubs are 110 mm wide, most 10+ speed bikes are 121, 126, 130, 135mm wide. Adding too many spacers means more axle flex and possible breakage. Some frames are just too difficult to respace well.
First is the "string method" for checking the alignment and rear drop out width.
Second is getting the dropouts parallel to each other.
Third is the chain line.
Everything you need is at the Sheldon Brown page on frame alignment. Pictures included.
https://www.sheldonbrown.com/frame-spacing.html
These cheap gas pipe frames are the easiest to realign. Some get (oopsie) bent when someone drives the car in to the garage and squeezes the bike up against the wall.
Aluminum and carbon fiber frames are not straighten-able without destroying them for good. Cromo frames are so much stronger it's hard to cold set them.
I respace and align several frames every year. Some due to damage, mostly because I do a lot of single speed conversions on derailleur bikes. . Respacing a frame to fit a hub vs adding spacers to an axle to fit a particular frame. Just depends on the frame construction & hub. Most single speed hubs are 110 mm wide, most 10+ speed bikes are 121, 126, 130, 135mm wide. Adding too many spacers means more axle flex and possible breakage. Some frames are just too difficult to respace well.
Last edited:
I have both versions of that park tool but a 2x4 works better for overall alignment. (different hook sizes) I only use the two park tools (at the same time) when I'm trying to bend a stay mid-stay without bending the stay at the bb a the same time. If you use the park tool you need something to leverage against. Just having 1 park tool only works if you have an immovable anchor for the frame. I've broken 4 bench vises in half trying to remove bb cups, etc, and my bench (with the vise) isn't rock solid.
With the 2x4 you use the floor and gently step on it. Worse case you have to lift the 2x4 and have the wife stand on the frame to hold it down.
With the 2x4 you use the floor and gently step on it. Worse case you have to lift the 2x4 and have the wife stand on the frame to hold it down.
