Tuesday, January 01, 2008


Now there's a heavy topic. We've been trained to believe that weight is one of the most key criteria regarding bicycle performance. It makes sense logically, one can even calculate energy saved over a course based a on certain weight saving. As a consequence, the importance of weight takes an impregnable position in our imaginations.

I don't subscribe to this point of view. There is no question, that if the differences are great enough, weight will slow us down on the bike. But how much is too much? As Richards Sachs points out, we don't bench press bike frames, and frames don't contribute to rotating weight. So is a super light weight bike really a performance advantage compared what was available in the early 70's. For those of you who weren't around then, a 22 pound bike was pretty competitive. Considering the UCI allows bikes to weigh as little as (approximately) 15 pounds, we're looking at a 7 pound difference between then and now.

Well, if you're as big as me, that seven pounds is something like 3% of the combined weight of bike and rider. Which sounds like it might make a difference. The studies that I've seen, however, don't seem to show that results vary based on weight. It seems like a disconnect, but when time counts, ability and attitude appear to outweigh weight.

Manufacturers are busy lobbying the UCI to lower the minimum weight allowed for a bike. Given that all the teams and riders have access to similar equipment, this shouldn't change the quality of competition or the order of results. But it will give manufacturers bragging rights for a few more years of product cycles. And, fundamentally, the bicycle business has long been one of product cycles. This wasn't always so. There was a time when changes came more slowly, but Shimano made this one of it's key tools to survive the various bicycle market booms and busts - as did their clients: the bike manufactures.

Now days, many folks get the itch to buy on a regular basis. For some folks this happens annually, for others every x number of years. Don't think for a moment, however, that bicycle sales are based primarily on a combination of bikes wearing out, or becoming fundamentally obsolete, and new cyclists joining the market. There is a huge segment of move-up and replacement (which may be merely an addition to one's stable) purchases that drive the market, especially on the upper end.

Let's face it, our modern economy puts lots of emphasis on growing consumption - often at the cost of product longevity. So what I've described clearly isn't unique to the bike sector.

Having said that, I prefer to build something that will survive through multiple generations. I think, that for this to happen, there are three things that must be right about a product: 1) It has to be durable; 2) It must be inherently functional; 3) It needs to exhibit a fundamental aesthetic that lasts over time.

As a result, my bikes generally won't be the lightest in the market, even when I use carbon fiber. That doesn't mean that I don't experiment with light weight frames, nor that I won't deliver something light to a client. But I do want my frames to last and build them accordingly.

Before and after WWII, top French builders competed in technical trials where their bikes were tested and judged for functionality, durability and performance. The best examples weighed in somewhere around 16-17 pounds with fat tires, fenders, racks & bags, front and rear lights, and pumps. Today, except for a couple of preserved examples from those contests, I am unaware of any bikes today that are that light while being so fully equipped. After all, its hard to build a bike that capable and that light. And frankly, one should presume that such a bike wouldn't have a very long life under daily use. In fact, those same French builders generally sold the public similar bikes, but at weights starting at 21-22 pounds.

Bicycle weight has long been viewed as a performance issue, but low weight reduces longevity.

Having said all of the above, I remain intrigued by bike weight. More and more, I consider how everything, apart from the frame, contributes to the total bike weights we see today. This too is much like what the old French builders did. As part of their program to reach low weights, they'd replace steel bolts with aluminum, or cut a dish into the heads of bolts, they'd cut away pedal cages, and make their own brakes or stems to lose weight.

Today builders have to consider legal liability when modifying components. And we have to consider how many components are made to work as part of a system - where changes to one piece could throw off functionality of everything. On the other hand, we can select from components and groups to achieve low weight in ways the old French builders generally couldn't.

Today, its possible to purchase a pair of wheels that weighs less than a Kilogram. That's darn light. The new Red group from SRAM is claimed to be less than 2 Kilo's. Given that, it should be easy to build a bike today from commercially available products that weighs less than 5.5 Kilo's, or around 12 pounds. Will this make you a faster rider? Personally, I doubt it. But all this drives me to wonder what a reliable steel-framed bike should weigh.

In a smallish size, I think that a 650B based frame, built up with Columbus Spirit for lugs might come in around 3 pounds. Add another pound and a half for the fork, and we're at 4.5 pounds. What do you suppose we can do with this?

Well, I've been weighing some components lately. I'll be publishing the results in another post - but by and large SRAM seems to offer accurate numbers. Preliminary results suggest that my build kit will weigh in around 12.4 pounds, which combined with the frame and fork totals 16.9 pounds. Frankly, this doesn't seem believable to me, so it looks like a test is in order. But first let me describe the build kit so you can see that I'm not planning to do anything crazy or radical.

The core will be a SRAM Force drive train including: braze-on front derailer, rear derailler, 1090R chain (weighed in its heavy packaging), SRAM OG-1070 steel cluster in a 12-25 configuration, Dual Control levers (weighed with full cables and casings), and carbon compact crankset with the normal Exo-Drive BB cups. To this add: Thomson Elite seatpost, Fizik Arione saddle (a Sella Itala SLR would save 0.2 pounds), Tektro Quartz CR720 cantilever brakes (w/ hardware), 650Bx32 tires and a set of hand built wheels comprised of White Industries H2 sealed bearing hubs, laced 32 x 3-cross to a set of CTA Razor rims using Sapim spokes (front 14/17 ga, rear 14/15 ga). There you have it. None of this is cheap stuff, but it's not esoteric, flimsy, or hyper expensive either. Seems doable - I'll share more info as progress is made.

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