UBI Day 8: Suspension Forks and Frame Prep

We started the day with a discussion of modern suspension components and how best to tune a suspension equipped bicycle to a given rider.  While there is obviously a lot of subjectivity in what “feels” right to a particular rider, there are some general guidelines that will provide, at minimum, a good starting point for these types of adjustments.  Definitions and adjustments for sag, rebound damping, compression damping, spring rate, etc. were all explored.  We then removed the lower fork tubes from a typical “all-mountain” fork and performed a routine service and oil change.  After completing the suspension work we segued into metallurgy and frame construction materials and techniques.  This eventually led us to the proper way to prep a frame prior to bolting any components to it.  We discussed and performed bottom bracket thread chasing and facing, as well as head tube facing and reaming.  These operations are often necessary to achieve concentric and parallel bearing surfaces for those components.  This has become even more critical now that a 2 piece ceramic bottom bracket might cost $200 and will wear much more quickly if it’s bearings are not parallel to each other in the frame.  These sorts of small, but critical, details are often overlooked by the typical mechanic at the typical shop.  Caveat Emptor!


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s