Is fork offset same as trail?

Simply put, fork offset, or fork rake, is the distance between the front axle and the steering axis – the imaginary line running straight through the midpoint of the steerer tube. Trail is the horizontal distance between the steering axis and the contact patch of the front tyre.

How does fork offset affect trail?

Increasing fork offset reduces trail. Larger wheels increase trail. With a larger wheel (e.g., a 29” wheel) the axle is higher off the ground compared to a smaller wheel. If you draw a line through the steering axis to the ground, it intersects the ground farther forward of the axle, increasing trail.

How does fork offset affect a mountain bike?

Decreasing trail improves agility. The front wheel feels easier to turn and it can make a bike feel more nimble. Trail on a mountain bike is affected by three factors: fork offset, wheel size, and head angle. Reducing fork offset increases trail. Increasing fork offset reduces trail. Larger wheels increase trail.

What’s the difference between the offset and the trail?

Offset is how far the front axle is ‘offset’ from the steering axis. Trail is the distance between the contact patch of the tyre and where the head angle line hits the floor. The bigger the offset the shorter the trail figure. And vice versa, the shorter the offset the larger the trail figure.

How does head tube angle affect fork offset?

As I had said before, slacking the head tube angle gives you more trail, as well as reducing the forks offset. This is giving bikes a much longer than previous trail numbers, and with a longer trail, you will typically have a more stable or slow front end steering.

Which is an example of a reduced offset fork?

On this example, the head tube angle does not change. Different brands are taking slightly different approaches in their use of reduced offset forks. With their most aggressive trail bikes, the Sentinel and the Patrol, Transition has paired a lower offset fork with an extremely slack head-angle – 64° – resulting in very long trail numbers.