Reports of the demise of this Web site are greatly exaggerated! We at sheldonbrown.com thank Harris Cyclery for its support over the years. Harris Cyclery has closed, but we keep going. Keep visiting the site for new and updated articles, and news about possible new affilations.


Search sheldonbrown.com and sheldonbrown.org

find us on FB

More Articles by Jobst Brandt
Next: Stuck Handlebar Stem
Previous: SRAM (formerly SACHS) Power-links

spoke

Subject: Aligning a Fork
From: Jobst Brandt
Date: May 11, 2001

aka Bicycle pulls to one side

Riders occasionally complain that their bicycle pulls to one side when ridden no-hands. That is, the rider must lean off to one side to ride straight ahead. This symptom can be from a wheel that is in crooked, something that is easily checked by observing whether the tire is centered under the brake bolt, or by just reversing the wheel to see whether the wheel is improperly centered.

Assuming the bicycle still pulls to one side, the reason is usually that the fork is bent from a side impact. A bend from a frontal impact is easily seen because the blades have a rearward bend just below the fork crown where they should be straight both fore and aft and side to side. A frontal bend usually gives a side bend as well, because the blades are not identical and tend to skew to one side. This is harder to fix and requires fixturing.

If the fork is only bent to the side, the correction must be to the side to which the rider must lean when riding no-hands. This bend can be done carefully by bending one blade at a time.

Lay the bicycle on its side, front wheel removed. Place the rubber-soled foot inside the crown of the fork and pull the upper blade until the gap at the fork end increases by a couple of millimeters. This should be measured. With the foot in the same place, pull the other fork blade until the original spacing is restored. Ride the bicycle and assess the difference. Repeat if necessary. This must be done with a strong arm and a bit of skill but it is simple.

If you have a non-steel bicycle, buy a new fork.

Jobst Brandt

[The more primitive the tools, the more skill is required to get a repair right. Brandt describes a "heroic" repair, or a "desperation" repair, requiring skillful muscle control to avoid bending the fork too far, potentially ruining it, and skillful, repeated measurement.

When a steel fork is bent backward, usually the steerer (inside the head tube) will be bent, not only the fork blades. I've successfully straightened forks by placing the crown between wooden blocks in a vise and first straightening the steerer by hauling on it with a close-fitting pipe fitted over it, measuring its straightness with a straightedge. Once I've finished that, I straightened the blades with blows of a rubber mallet, measuring alignment relative to the steerer. But a fork-straightening jig does a much quicker job -- see the article on frame repairs -- John Allen.]

Spoke Divider

More Articles by Jobst Brandt
Next: Stuck Handlebar Stem
Previous: SRAM (formerly SACHS) Power-links

Spoke Divider

Spoke Divider

Articles by Sheldon Brown and others
Harris
Home
Beginners Brakes Commuting
Lights
Cycle-
Computers
Do-It-
Yourself
Essays
Family
Cycling
Fixed Gear
Singlespeed
Frames Gears &
Drivetrain
Bicycle
Humor
Bicycle
Glossary
Bicycle
Links
Old
Bikes
Repair
Tips
Tandems Touring What's
New
Wheels Sheldon
Brown

Reports of the demise of this Web site are greatly exaggerated! We at sheldonbrown.com thank Harris Cyclery for its support over the years. Harris Cyclery has closed, but we keep going. Keep visiting the site for new and updated articles, and news about possible new affilations.

Harris Cyclery Home Page

If you would like to make a link or bookmark to this page, the URL is:
https://www.sheldonbrown.com/brandt/align-fork.html

Last Updated: by John Allen