Tapered steerer tube: what it is
It's a steerer tube with two diameters: 1.5" at the bottom (lower bearing) and 1.125" at the top (upper bearing). It's the modern standard. A straight steerer fork (1.125") needs a reducer to fit a tapered frame, and a tapered steerer one doesn't fit a straight frame. Before buying, confirm what fork fits your bike and check the cluster guide.
"Tapered" describes the shape of the tube, not the quality. What really matters to you is whether it fits your frame's steering: that's where people go wrong when buying.
What the tapered tube is
The steerer tube is the part of the fork that goes inside the frame and turns on the headset bearings. On a tapered tube, that tube doesn't have a single diameter: it's wider at the bottom (1.5") and thinner at the top (1.125"). That shape gives more stiffness to the steering area and is the modern standard on most current bikes.
Quick table
When it fits and when it doesn't
Straight steerer fork in a tapered frame: doable, but with a reducer that adapts the lower bearing. Without that piece it doesn't fit right.
Tapered steerer fork in a straight frame: doesn't fit. The 1.5" lower section doesn't fit a steering meant for a 1.125" straight steerer, and there's no reducer that solves it in that direction.
That's why, before buying a fork, the first thing is to know what steering your frame has. Check what fork fits your bike so you don't get the tube wrong.
Tell us your bike's make and model and we'll tell you whether your steering is tapered or straight and which fork to look for. Message us on WhatsApp
Frequently asked questions
What is a tapered tube?
A steerer tube with 1.5" at the bottom and 1.125" at the top. It's the modern standard and gives more stiffness to the steering.
Does a straight one fit a tapered frame?
Only with a reducer: a 1.125" straight steerer fork needs that piece to fit a tapered frame.
Does a tapered one fit a straight frame?
No. The 1.5" lower section doesn't fit a straight steerer steering, and there's no reducer that solves it.
Related
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