Bike geometry, original specs and upgrades.
Understand its geometry, find its original build, and keep track of what you have changed.
Understanding bike geometry: what the numbers describe
A plain-English guide to reading a bike geometry chart, comparing the right size, and understanding what the measurements cannot tell you.
Stack and reach: a useful way to compare bike frames
Learn what stack and reach measure, compare two real Trek road frames by size, and understand why these numbers do not predict fit on their own.
How to find your bike’s original specifications
A practical source trail for finding the geometry chart, original parts list, manuals, and service information for a specific bike.
How to identify your bike’s model year and trim
Use paperwork, manufacturer archives, labels, and frame details to narrow a bike identity without guessing from paint or a serial number alone.
Stock parts and upgrades: record what is on your bike now
Keep the factory build as a reference while making a clear record of replacements, upgrades, and parts whose exact identity is still unknown.