# Bicycle Mechanics - Changing forks affects handling?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.

View Full Version : Changing forks affects handling?

Brian_T
11-20-02, 03:03 PM
I just started putting together a Surly Steamroller fixie for riding on the trails and have been thinking of upgrading the road fork for a Surly 'cross model. However, I have heard that the 'cross fork will raise the head tube 12mm as it's configured a bit longer than the road fork (it's really configured for an entirely different frame.)

Anyway, what would raising the head tube 12mm really do to the handling of the bike? As I'm pulling together pieces to make this bike road-ready I'm finding myself more and more theorizing about equipment combinations without any real empirical evidence. It's a dangerous racket. :)

pokey
11-20-02, 04:31 PM
Why don't you ask Surly? Is the rake different too?

D*Alex
11-21-02, 07:27 AM

<phone rings> "Yeah- dis is Surly Customer Service! What the h3ll do ya want??!! C'mon-I haven't got all day!!"

:D

faith
11-21-02, 08:17 AM
Brian_T

Since you’ve asked, “What would raising the head tube 12mm really do to the handling of the bike?” Try to understand the function of the fork in steering. The steering axis is a line through the head tube, the term “rake” is used to quantify the amount of distance the front wheel axial is set forward from the steering axis. Generally it is thought the more rake, the slower the response however the more “stable” the ride. On the other side of the geometry, the EZ rider chopper motorcycles are an extreme in steering angle; nice traveling in a straight line, but tight cornering wasn’t their forte.

I’m certain other forum members will enlighten you on additional aspects to be considered. Pokey directed you to the frame vendor, a wise consideration since raising the head tube may change the steering axis angle and in theory may affect the rake for a given fork. Be advised that with any “cycle” changing steering geometry can cause some very strange things to begin to happen at high speed, trust me on this!

Cheers; and God Bless