Eli5: Why do offroad bicycles have fatter tires while offroad motorcycles have skinnier tires?

Question

Eli5: Why do offroad bicycles have fatter tires while offroad motorcycles have skinnier tires?

In: 17

Answer 1

First of all your premise is incorrect.
Typical mountain bike (bicycle) tires are around 2.5” (~60mm) wide. A typical motorcycle tire is 4-5” wide (120-140mm). There are some variations like fat tire bicycles, but generally these are pretty close — with motorcycles having wider tires than bicycles.

Motorcycles need the wider tires for traction since the rear tire is driven by an engine, not a human. The front tires are not as wide as the rear in order to maintain steering feel and agility, but they’re still wider than most typical mountain bike tires.