Friday, May 9, 2014

A Tale of Two Bikes

I've written before about weight and bicycles. I've argued that reliability, durability, comfort, and convenience (and even beauty) all trump weight on my list of priorities. If fenders allow me to ride comfortably without the wet, muddy stripe up my backside when the roads are wet, then I'm happy to carry the extra weight. If racks and bags allow me to carry loads on my bike instead of my back, I will gladly accept the weight. If a lugged steel frame and fork will prove to be more reliable and durable, and please my eye more than a "popped-out-of-a-mold" carbon bike, then I will choose the steel frame every time. Weight simply doesn't make as much difference as we are led to believe. Not in performance, and certainly not in enjoyment.

No doubt, a lighter bike may feel faster. But in actual real-world performance, especially in the non-racing world, the difference is more perception than reality. Weight can make a difference, but one needs to be talking about pounds, not grams. And there are other factors that make a much bigger difference than weight.

Two Bikes

I have two bikes that are very similar in many ways, but have a large difference in weight. Both are made by the fine folks at Mercian, with frames made of the same Reynolds 725 heat-treated chrome-moly. Both are equipped with recent-era Campagnolo components and similar wheels. One has a longer wheelbase and slightly more relaxed frame angles. Stripped down, the bikes are very similar, but one of them is fully loaded up for touring and commuting, with front and rear racks, fenders, multiple bags, and lights. Heading out the door on the way to work, the loaded bike carries roughly 15 - 18 pounds more than the stripped down version.

Fully loaded up, with full bags, ready for the commute to work, this bike pushes nearly 40 pounds
Similar frame and componentry, but essentially "stripped down," this bike weighs around 22 pounds or so.
With such a large difference in weight, one would fully expect there to be a huge difference in performance -- seriously -- the extra pounds I carry in gear and accessories alone are more than the complete weight of one of the latest generation of carbon fiber w√ľnderbikes. So how does that affect my riding?

My commute to work is just over 13 miles and typically takes me about 50 minutes. The ride home is a bit over 15 miles and takes me an hour. It varies a little from day to day, but rarely by more than a minute or two plus or minus.

One morning when the weather was good, and the afternoon forecast was looking even better, and I had very little that I needed to carry with me to work, I chose to ride the lighter, stripped down bike. Dropping roughly 15 pounds, I have to say, I felt fast. The bike surged forward with every pedal stroke. On the long, slow slog of a climb I encounter every morning, I felt like I was flying. The bike felt weightless rocking side-to-side beneath me as I climbed out of the saddle (with prose like that, I could review bikes for Bicycling. All I need to add is "laterally stiff and vertically compliant"). When I pulled into the parking lot at work, I found I had made it in 45 minutes. Five minutes faster! My fastest commute ever.

Before any weight-weenies start rejoicing (do weight-weenies even read this blog?) I should point out something else that I failed to mention. There are over 30 traffic lights along my route between home and work -- more than two lights per mile! On the morning of my personal-record-best ride, I had the nearly miraculous luck to hit every green light for more than 13 miles. Every single one was green. At no point did I have to stop for the whole commute. So, was my 5-minutes-faster time because I was on a lighter bike, or because of my unbelievable luck with the lights? No question, luck had something to do with it. But how much?

About a month later, I got my answer. Riding my regular commuting bike, loaded up with my usual bags and gear, I had an unexpected repeat of my luck with the traffic lights: once again, I had managed to hit every light green all the way from home to work. No stopping and starting. No lost momentum. I did not feel the bike surge forward with every pedal stroke. I could feel the extra pounds shift side-to-side beneath me as I climbed the long, slow incline. But I arrived at work in 46 minutes; a minute off my best time. It's true that far less time than that would be the difference between winning and losing in a race -- but this was no race. In any other situation, such a small difference is totally inconsequential.

I've read that studies show there is a difference of 1 mph in average speed for every 12 pounds added to or subtracted from a bike. Although hardly exact or scientific, my little informal experience above seems fairly consistent with that result. Clearly, there are other factors that can potentially make a bigger difference than weight. Traffic lights obviously make a difference. Wind direction makes a difference. I've found that riding to work into a strong headwind can add a good 5 minutes to my usual time. My own personal physical state makes a difference, too. Some days I just feel faster -- I get into a rhythm, my lungs and legs feel great, and everything just comes together. Other days . . . well, not.

I guess what I'm getting at here is that the quest for ever lighter bikes and components isn't really transforming the experience of bicycling in any meaningful way. The over-sized, swollen-looking frames and components rendered in carbon fiber might be bringing the weight of bicycles into sub-16-pound territory, but what's the point? If they are visually atrocious, less durable, less reliable, less practical (can they accept fenders and racks?), while simultaneously more complicated and more expensive, then what do we gain?

9 comments:

  1. Both of your Mercians are very good looking bikes. How many do you have in your stable anyhow?

    Here is an interview of a UK wheelbuilder that I think would be right up your alley: http://andywaterman.info/harry-rowland-cyclist-magazine-wheels/

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    1. Thanks, Nathan -- There are 7 Mercians currently. Crazy, really. Thanks for the article link -- I'll be sure to check it out.

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  2. That was a very interesting post. My sole derailleur road bike (I have two fixed gear road bikes and a Fargo for off road riding) is a Rivendell Rambouillet built up very nicely but with no thought for weight. Weight is added by a Shutter Precision front dynohub, a Cyo headlight, an auxiliary battery headlight and two battery tail lights, and a Fly rack -- not to mention a sizeable seat wedge and a full-size frame pump. I haven't weighed it recently, but I think it is about 25 lb ready to ride but without errand/commuting luggage or bottles.

    I'd recently been wondering if it would be worth the while to strip it and make it a gofast bike, or else to find a classic '70s or early '80s racing frame (my brother has a very early Bertin that I could buy cheap) and build up a fast road bike with multiple gears. Thanks to your anecdote, I now think that such an exercise might be largely a waste of time.

    OTOH, my two fixed gear road bikes are both custom 559 or 571 wheel Rivendells, one a 57 and the other a 58 but otherwise identical except for color and lugs. The '99 was built as a strict gofast: no provision for a rear brake, one set of bottle cage mounts, no braze-ons. It weighs about 17 3/4 lb with very light 650C wheels and Michelin Pro Race 3 23s; no seat wedge or bottle but with the single Iris cage. 75" gear. The other has two cages, a SON 20R and Edeluxe, a custom ss rear rack, a dynamo and a battery rear light, a bell, and slightly heavier pedals (Dura Ace SPD versus original edition Look Keo Maxes). 559X32 mm actual wire bead Kojaks. Weight built but no luggage other than seat wedge or bottles is about 23 lb. 70" gear. Both bikes have similar wheels: different hubs but 559 and 571 Sun M14A/ME14A rims respectively.

    Whether it is the wheels or the 5 lb difference in weight or the tires or simply the higher gearin, the gofast is very definitely faster up hills, gauging this by rpm along the same sections. Every time I think to myself, "I don't need a gofast; most of my riding is errand riding", I ride a few hills on the gofast and experience once again the delight of climbing on a light bike. I daresay that if your route included (as mine did back when I commuted across town 15-16 miles each way) some 7 miles of climbing, mostly gradual but with a few steep 1 mile hills, you'd be considerably faster on the light bike.

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    1. Thanks for the comments! You mention the Shutter Precision dynohub -- I'd be interested to know how it compares to the SON, which I see you also have. The SP being much cheaper, I wonder how it stacks up.

      I wouldn't want you to be left with the impression that a lightweight "go fast" bike would be a waste of time. I really enjoy riding that black Mercian. It might not be significantly faster as measured -- but as I pointed out, it certainly "feels" fast, and that is something. If I'm just going out to ride and the weather is clear and I don't have anything to carry beyond a water bottle and a banana or something, a "stripped down" bike is the one I'll grab.

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    2. The published numbers -- weight, efficiency, drag -- for the SP are up there with SON's best. As for real life, I can't say, since I've not used it long enough -- I've had it about a year and, frankly, I've used it only twice or so -- I work for myself, at home, and night riding is not a frequent activity.

      FWIW, in such use as I've given it it seems entirely competent: I notice no drag when the Cyo is on or off and, altogether, I can't say that I can tell any actual difference between the SP (bought used but NIB for $75) and the SON 20 R (full retail). Once or twice I thought I noticed vibration, but when I tried to repeat it, it wasn't there. Having used the SON 28, the SON 20R, and two DH-3N72s at about $120 at bike shop prices, I'd have to say that, at least from short term evidence, the SP is the reasonable man's choice.

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    3. Thanks for the info -- I've considered going with a good dynohub, but they can be awfully expensive. The SP is a good bit more affordable, but I wondered how it stacked up. Thank you!

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  3. I recently stripped all my racks, bags, goo-gahs, and aluminum full wrap fenders off of my Masi CX. Now, I'm riding with a spare tire, a pump, two water bottles, small plastic fenders, and small head and tail light. The difference: I ride at exactly the same speed as before, but the bike is much more fun to ride.

    I'll build something else up that's better suited for hauling stuff around with and foul weather commuting.

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  4. My commute has a couple of ~14% grade hills---I notice and prefer to get rid of every extra ounce for those. I also note that panniers create a LOT of wind resistance and slow me down by a substantial amount, so I am willing to wear a backpack when I don't have a lot of stuff to take with me.

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    1. I much prefer carrying on the bike than my body. Riding with backpacks, messenger bags, or whatever, traps so much heat -- and SWEAT! Nice to hear from you DeVon!

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