Wednesday, December 6, 2017

Developing standards

Ah, the ever-changing standards. We love them and hate them. You would think that standards are here for a reason - to make everyone's life easier by designing components that fit together. Unfortunately, reality is less than perfect and that's why we have this modern bottom bracket mess.
Obligatory XKCD comic.

Bicycle bottom brackets are a good example what trying to make good better may lead to. Nearly two decades ago, the most common bottom bracket type was the one with square tapers on a small, steel spindle, assembled into a sealed cartridge.
Square taper bottom bracket cartridge (Source: BikeRumor)

Then, lightweight cranksets arrived and with the tendency to make cranks stiffer, lighter and stronger, a larger-diameter spindle was needed. With bearings sitting inside the frame, there was no space for it so outboard bearings were developed, with cups threaded into the same BSA-threaded frame shell. That worked pretty well and still works today.

But then some companies took it a step further and tried to "improve" it by removing outboard cups and threads, by press-fitting bearings directly into frame. Multiple new "standards" appeared: BB90, BB86, PF30, BB386EVO... Most of them were less than perfect. With frequent tendency to creaking noises due to sub-standard part tolerances, cyclists started to abandon these inventions and go back to what worked just fine. In fact, that's why Chris King developed T47 standard (yes, yet another one) that uses threaded frame shell and can adapt any other BB type to work noise-free.

You may have your own preference and opinion what the best bottom bracket standard is and I'm not going to try to convince you otherwise.

That's not what I wanted to write about. I wanted to focus on... screws. You know, these little parts that hold all of it together.

Decades ago, most screws on bicycles had hex heads, requiring a multitude of various size spanners to make simplest adjustments. Headsets were threaded with large hex nut, cranks had cottered pins with hex head screws. It worked but wasn't pretty.
Hex head stem bolt with large-diameter hex hed nut securing threaded fork shaft. (Source: MyTenSpeeds).

Then things got better. Essentially all bicycle and component manufacturers switched to hex socket screws that require few hex keys (Allen wrenches) only. Thank God they chose metric screws, likely to utter disappointment of all Americans believing in their "standards".
Socket hex head screws are a norm in bicycle world today...

but will they soon be replaced by Torx standard?

This unification of screws was definitely well-received not only by cyclists but also bike mechanics. As a result, now, modern bikes can be put together with just few basic tools, notably the 4mm and 5mm hex keys. With these two small wrenches, you can assemble nearly the entire bike with a few exceptions that require (and always did) specialized solutions such as cassette, chain or headset cups.

Unfortunately, there is ongoing process of improving things that already work and as such we welcome our new overlords - Torx screws. It seems that some bike mechanics or users have problems with stripping of hex sockets, likely by using low quality tools. As such, Torx screws are becoming a new standard as those harder to strip. Do we need them? I'm not sure. But if you think you do, I suggest we replace all hex sockets with Torx and keep it consistent. We don't want to go back to the 1950-era of carrying a tool chest on every ride.

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