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Bottom Bracket Standards

: The irony is that the newest, most relevant bottom bracket standards, such as BB90 and BB30, aren’t about bottom brackets. They’re about frame construction, and frame stiffness.

Frame Stiffness

: What follows below may be a line of reasoning I have to eventually repudiate. My intention is to deliver my thesis with maximum caution and minimum hubris, in case I need to eat crow later.

Armstrong on his Tri Bike

: Things are changing for Lance. Like, his position. What goes around comes around, and he's laregely come back 'round to his pre-bike-race tri position, with an assist from Slowtwitch forum members.

The final Slice

: As many Slowtwitchers know, I and the Slice I rode in the Tour of California time trial did not deliver each other safely to the finish line. Nevertheless, I did promise readers a recap of that ...

The Slice is built (sort of)

: As the late senator Moynihan put it, "Everyone is entitled to his own opinions, but not his own math." Okay, he said facts, not math, but the idea is the same. But now on to that Cannondale Slice.

The correct length of your chain

: Do you know how to determine your bike's correct chain length? Do you know why it's important? It has to do with course topography, and choosing the right freewheel for your race. You don't have ...

Torque wrenches (and one in particular)

: In the old old days of cycling (when I was 25 or so), everything was made of steel and forged aluminum. Back then we needed torque wrenches. In today's age of carbon, you really need a torque ...

Working with crown races

: Do you want to install (and uninstall) your fork on your bike? If so, you need to get the crown race on and off. There are tools for sale that represent the incorrect way to tackle this job. Here ...

The Miter block

: Also known as steerer cutting guide, or fork saw guide, I prefer miter block, because I cut a lot more than fork steerers with it. This tool is in almost constant use—frequently seen in the jaws ...

The case for wrenching

: Two times in 20 years has a bike I've worked on failed during a race: my own, in a race I traveled around the world to get to; and one ridden by Lance Armstrong in a national championship. But, I'm ...

A man-skills workshop

: Updated from its original publication in 2004, this article is the answer to a Slowtwitch Forum user who once posted: "[Blank] the car, I'm putting a bike workshop in the garage." His post asked for ...

Tools every bike tinkerer needs

: What follows herein is the bike tinkerer's list of essential tools. Any less and you're a caveman. All these specialty tools can be had for quite a small sum compared with the many thousands a pro ...

A Day in the Life of a Wind Tunnel

: I was the lone industry observer invited to the wind tunnel testing of the finished S5 product. I took copious notes, in order to describe the mechanics of the wind tunnel process.

Why Wheel Aerodynamics Can Outweigh Wheel Weight and Inertia

: The common wisdom is that wheel mass, since it is rotating, counts "doubly bad" as compared to non-rotating mass. There's a grain of truth to this common wisdom, but it doesn't tell the ...

Cervelo P4 in the Tunnel

: Cervelo took several superbikes to the San Diego wind tunnel last month and tested them all exhaustively and comprehensively. Slowtwitch was there for the entire exercise. Here's the first of ...

Extensions overhaul

: We need to overhaul extension shapes. After much experimentation, what have we learned? The spatial relationship between armrests and extensions is important, and, no more horizontal grips.

Memo to bike maker: change spec

: How often are bikes spec'd from the manufacturer in ways destined to give the customer a fighting chance of riding the bike successfully without swapping parts?

52cm sizing comparison

: At about 51cm or 52cm you enter a size range where just about everybody's bikes are built with 700c wheels. Here, there's a convergence of geometry, but a divergence in handling.

58cm sizing comparison

: When you get to the 58cm size, tri bikes diverge geometrically. Why? Because they can. The height of these bikes is similar, one to the next. But in reach, there's more of a divergence.

Inputs and outputs: Volume 2

: What is important? What ought to matter? The answers depend on who you are and what are you're trying to achieve. You are a tri bike's designer, for the purpose here; good steering geometry the ...

Small bike sizing comparison

: Are you 5'6" or shorter, or have an interest in one who is? Here is an assortment of small tri bikes, and where they fall along the geometric gradient of long, short, tall and narrow.

Inputs and Outputs: Volume 1

: In about a month, I'll have two bikes in my garage: a P3 and a Slice. The P3 was an output, that is, it was the result of a process. The Slice was an input: It commenced a process. Confused? ...

Empty space finds new traction

: Even if old ideas fade away, if they have value, they'll kick around and reappear. So it is with "empty space" between a bicycle's fork and its wheel.

What's in a tube?

: This, a companion to "What's in a tire," describes the difference between butyl and latex tubes, and also the calculus of tire pressure, and how to choose the right pressure for a race course.

Is Chrissie Slowtwitch approved?

: Chrissie Wellington rides hard. Very hard. And very fast. But does her position fall in line with what we teach and preach at Slowtwitch U, or is she an outlier bucking the trend?

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