Part 1 showed how clincher rims can alter spoke tension when tires are inflated:
(1) Outward splaying of brake tracks, changing the rim shape, dropping spoke tension.
(2) Inflation pressure down on the rim bed, a constricting force that shrinks the rim causing measurable tension loss.
Tension loss can be confusing to wheel builders following tension recommendations from rim makers. We need to know why this happens and when to worry.
Here in Part 2 we explore how tires, independent of inflation, affect this dynamic.
First let’s review tire and rim sizing for those less acquainted. Why are they made to the sizes we see?