So a frame with an original 501 decal can't be from the 70', 531 decal doesn't help as much because of the range of years produced. Reynolds 531 tubing introduced around 1934, still used today Reynolds 501 tubing introduced around 1983). Shifting ramps and pins on cassettes/sprockets and chainrings (versus flat sprockets)įrame material (e.g., shift from tubular steel to use of CF and hydroformed aluminium)įrame tubing type (e.g. Style of shifters (brifters, triggers, etc.) threadless)īraking system (especially with mountain bikes: v-brake, direct pull, etc.) How the steerer attaches to the fork (quill vs. Quick releases versus contemporary through-axles old catalogues, fan websites)Ĭottered cranks vs square tapered or splined cranks and bottom brackets
The span of answers would include things such as:
To some extent, these will also help you narrow down the model as well as it will tell you what distinguishing features to look at.
Each 'answer' should address a different way to determine the manufacturing year of a bicycle. This is a canonical question that will hopefully encompass all of the questions we get asking us to determine what year a bicycle was manufactured (how old is my bike, how old is my frame, etc.).