Fork offset — also known as rake — is the distance between the axle and a straight line through the head head tube.
Offsetting the fork more (increasing offset) pushes the axle further in front of the head angle
. Reducing the offset — which is what many bike designers are doing today — pulls the axle closer.
Are bike forks interchangeable?
Will any fork fit my bike?
No
. When replacing forks it’s key to know your head tube diameter as you will need to pick a fork with a matching steerer tube.
Does offset of fork matter?
Fork offset — also known as rake — is the distance between the axle and a straight line through the head head tube.
Offsetting the fork more (increasing offset) pushes the axle further in front of the head angle
. Reducing the offset — which is what many bike designers are doing today — pulls the axle closer.
Does MTB fork offset matter?
Both the headtube angle and fork offset can change the length of the trail number
. By making the head tube angle slacker (decreasing the angle) you will make the trail longer. By reducing the fork offset, you will also make the trail longer.
What is reduced offset?
A reduced, 44mm offset fork
allows the rider to run a slacker geometry with a similar wheelbase, but still enjoy a stable steering platform without sacrificing traction, stability, and control
.
What does 44mm offset mean?
44mm vs 51mm Offset
44mm offset has
108.7mm
while the 51mm offset comes in at 101.7mm. This means that the 44mm offset will have a bit more stable platform. If we wanted to design the same amount of trail into the 51mm offset fork we would need to decrease the headtube angle.
How much difference does fork offset make?
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.
Is rake the same as offset?
Rake and Trail:
Fork Rake is also known as Offset
, which more accurately describes what it is: the hub’s offset from the steering axis. Not to be confused with the curvature of the fork blades, which some people think of as “rake”. Straight blade forks can have plenty of offset.
What does offset mean on MTB forks?
Key terms explained. Head angle is an imaginary line through the steering axis to the floor. 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.
Can you put a 130mm fork on a 100mm bike?
at 130mm you’ll probably be fine, I wouldn’t put anything bigger on there
. The kona frames are pretty strong, I used to run a 130mm fork on my 100mm jump bike for AM and a lottle more FR riding, I was fine.
Are MTB forks universal?
Any standard 1 1/8 29 fork will work
.
How do I choose a fork for my mountain bike?
What is bottom bracket offset?
BB offset, could be referring to “drop” which is
the distance the BB sits below the wheel centres
. A larger drop means a lower BB (generally), though on trials bikes, it’s the other way round as they like to (now) sit above wheel centre.
What is an offset MTB rim?
To start with, offset rims do one thing:
they equalize tension between the spokes on each side of the wheel
. This makes it less likely that the lower tension side spokes will go slack, fatigue, and eventually break. That’s all.
Can I run 27.5 wheels on a 29er fork?
Condensed Answer:
If the bike and the wheelset are designed for disc brakes, a 27.5” wheel will fit on a 29” frame and fork
. Since 27.5” wheels are smaller, their diameter will change the geometry of the bicycle in a manner that the rider may not appreciate.
What is 12mm wheel offset?
A wheel with a -12mm offset would have
a hub mounting surface 12mm inside of the wheel centerline, or closer to the back side of the wheel lip
. This type of wheel usually has a “deep” look as compared to a zero or positive offset wheel. Most all factory truck wheels are positive offset to one degree or another.
What does +45 offset mean?
For example, an ET45 wheel measurement has a positive offset of 45mm, which means that
the mounting face is 45mm in front of the centre line
. Conversely, a wheel with ET-12 will have a negative offset where the mounting face is 12mm behind the centre line of the wheel.
How can I increase my fork travel?
Does fork offset increase wheelbase?
A common one is the thought that a reduced offset fork will pull your front wheel towards you, significantly reducing the wheelbase length. In actuality,
the change is negligible
. In the case of a 29’er with a 65 degree head angle, going from a 51mm to a 44mm offset fork will reduce your wheelbase length by 5.78mm.
How does fork rake affect handling?
Fork rake is only part of the steering story, as
a greater fork rake will increase the wheelbase
, which is prevalent on endurance bikes to create stability. The below image shows an example of how an increase in fork offset or rake which reduces the amount of trail and as a consequence speeds up the bike’s handling.
What is rake on forks?
Fork rake is
the distance between the steering axis (blue line) and the fork blades (purple line) at the front wheel’s axle
. The measurement is taken in millimeters on a line extending from a right angle from the steering axis and bisecting the center of the axle (the orange line).
What does trail mean on a bike?
Trail is
the horizontal distance from where the front wheel touches the ground to where the steering axis intersects the ground
. The measurement is considered positive if the front wheel ground contact point is behind (towards the rear of the bike) the steering axis intersection with the ground.
