Friday, December 10, 2010

Reverse 'Weight Weenies'?

Alternating between the Royal H mixte and the Gazelle for transportation over the past few months, I've realised something funny: I have a minimum weight preference when it comes to commuter bikes. For fast cycling on hilly terrain, I love the feel of a light bike. But when riding for transportation in the city, the mixte is pretty much where I draw the line for how light I'd want my bicycle to be. Does that make me a reverse "weight weenie"?

What I like about commuting on heavier bikes, is that they tend to feel extremely sturdy in traffic. They also seem to have a more solid, commanding presence - useful when mixing it up with cars.  I have found that drivers give me more room when I am riding something big and heavy-looking, possibly because they are more worried about damage to their car, should they accidentally clip me. Alternatively, it could be that on a massive bike - combined with an upright posture - I might seem like a more "legitimate" commuter to drivers.  Whatever the reasons, I do tend to feel more comfortable and confident on a heavier bike in traffic than on a lighter one.

For me, the most important aspects of ride quality in a city bike are stability, comfort over pot holes and bumps, and the ability to accelerate and slow down while maintaining full control. And heavier bicycles tend to do better in those areas. I am not saying "the heavier the better." But I think it is important to recognise that some of the merits of traditional city bicycles cannot be separated from their traditional heftiness.

The nice thing about my mixte, is that it can go from being laden with bags for commuting, to being light and ready for a fast ride, in a matter of seconds. And, unlike most other light bikes I've ridden, this one is comfortable over bumps - a major plus. For those reasons, I have been riding the mixte for transportation more than I thought I would (the bike was originally intended for long country rides). But she is definitely my lower limit for how light of a bike I enjoy riding in traffic.

60 comments:

  1. oh no, I think you are right about this -- I rode my "road bike" to work a few times a long while back, and I certainly felt that it was far too "fast and light" for commuting among rush hour traffic (bikes, cars, etc...); and that's not even mentioning the lack of carrying ability.

    My commuting bike, though it is "slower" and heavier, is certainly the "bike for the job"... so to speak.

    Here's where the weight get it wrong; "weight", in the sense of a component/frame/etc, really only matters if you are looking to shave fractions of a second a mile over the course of many many many miles (you know... the pros? ;). For the rest of us in the real world, it's a fetishisation of cycling that makes the casual cyclist worry about grams.

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  2. If you actually do the math, the difference between a 20lb and 50lb bike on a 10-mile ride is literally seconds.

    I personally think the "stability" thing is a big deal. Sometimes I need to signal while braking, avoiding potholes, and leaning against the wind. Feels much safer on a big heavy bike.

    Frankly, I'm not really interested in any bikes under 50lb.

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  3. The only time weight is a problem for a commuter is if you need to pick up the bike to put it on a bus, or to carry it up stairs.

    I'm perfectly capable of hefting a 50 lb bike, so I don't need to worry about weight even for that reason. But I know my wife struggled to get the old Schwinn Breeze onto the bus rack, and that was one of her main reasons for deciding to look for a slightly lighter bike.

    The funny thing is, she likes her new bike so much that she rarely takes it on the bus now, preferring to ride the whole 12 mile round trip.

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  4. Joseph E - I shudder at the thought of putting my 50lb Gazelle on a bus! I was speaking solely of ride quality and not of the lifting/carrying logistics. And to be fair, I tend to cycle everywhere and don't hoist my bikes up buses and trains.

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  5. I think the slightly heavier bikes (35lbs) tend to deal much better with potholes and bumps than lighter bikes, but I don't actually have any of the really light bikes (+/- 20 lbs., 23mm or smaller tires)

    Sometimes it is useful to carry the bikes upstairs; at 50lbs + bags etc. I've stopped trying to carry my Gazelle - even for me this is a really heavy bike. I'd hate to lift it horizontally onto a bus rack.

    Delaware is a little more spread out than Boston/Cambridge, so I have used the buses on occasion. The problem with the DL1 and Gazelle is actually the wheelbase - it's too long for the racks on the buses.

    Stephen

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  6. mmm, I think that the things you discribe as comfort through to weight are more issues of a longer wheelbase and an upright position. Of course, this mostly comes with extra weight, because your frame will be less compact..

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  7. Yes, time-tested upright designs are indeed comfortable in a way that lighter weight bikes don't seem to be. And some of the newer, well equipped examples make it really easy to hop on the bike without a lot of preparation (lock, pump, generator lights, full chain case attached). But, it taked a bit of energy to get those big ones up to speed, so lots of starting/stopping or hills make them hard on my not so good knees. A well designed upright bike made with some thought to weight savings might be a good compromise. Cro-mo steel and lighter wheels would help, though some say it is the 'hi-ten' steel that gives the solid feeling ride.

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  8. lyen, i won't get into debate about how fast one can go on a heavy bike versus a light one, as that was the subject of debate awhile ago and i made my points then.

    velouria, one thing that you don't mention in your theory about stability of heavy versus light bikes for "transportation" cycling is the weight of the rider. if the rider is a 100lb, then the difference between a 30 lb bike and a 50 lb bike may feel substantial-- that weight difference alone is 20% of the rider's weight, and a 15% difference in overall weight. however, i'm 165 lb and i'm on the "light" side for males my height... the norm is more like 180-200 lb. so, for a 200 lb rider, the difference between a 30 lb bike and a 50 lb bike is only a 10% difference in rider weight. see what i mean? so to a really light person, a heavier bike may feel much more significant than it will to a heavier person.

    personally, i don't feel much difference in stability, per se, between my 25 lb bikes and my 50 lb DL1. what i DO feel a difference in my personal comfort level and confidence in dealing with traffic, which is dictated by the geometry of the bike (and also the tires), not the weight. so, your comparison between your mixte and your gazelle in terms of the *perception* of stability is not a good comparison because the riding positions and geometries are very different. the gazelle also has a much longer wheelbase, which contributes to stability. the only proper comparison that could be made would be to compare two bikes with very similar geometries but differing in weight.

    personally, i find myself riding my heavy bikes less and less, and my lightweight bikes more and more, even for commuting and doing errands. i'm hooked on lightweight bikes for several reasons, which have been discussed before.

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  9. pjotr007 - I agree that wheel base is a confounding variable here. But I've ridden bikes with long wheelbases that have a harsh ride, and those have been either aluminum or some cheap lightweight cromoly, probably including cheap lightweight wheels.

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  10. I too enjoy riding my Workcycles through the streets of my city. I feel comfortable and, to a certain degree, safe or perhaps I should say I feel "in control" on it. I rode a friends very lightweight roadbike with 23mm tires yesterday around a parking lot. I felt like I was leaning over so far that I was in a freefall, constantly falling forward over the handlebars. I had to keep pedaling to keep myself from going over!

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  11. somervillain - I am actually not comparing my Royal H to the Gazelle in terms of stability, because they are both very stable. (But I don't think my custom-made mixte where every angle, measurement and piece of tubing was thought through, is representative of what a bike in that category usually feels like to ride.)

    I understand the concept that the overall weight of the bike+rider includes the weight of the rider. But I am talking here about the feel of the bike itself from the cyclist's point of view, holding the person's weight constant - the way a bike feels underneath you when you cycle, as well as when you are stopped at intersections.

    Regarding your personal preferences: What about harshness of ride? Compared to, say, the DL-1? I can understand that the lighter-weight bikes you now prefer to ride are more agile, faster and easier uphills, and if that is your priority then it makes sense for you to choose them. But I doubt they are more comfortable than Roadster-style bikes.

    What I am describing is a personal preference and it is not meant to negate differing preferences. I know people who, having discovered mixtes, dump their heavy 3-speeds like hot potatoes because the mixte is lighter. They acknowledge that the ride quality is harsher, but aren't bothered. I also know hard-core roadies who, when it comes to transportation, will ride only a heavy Roadster -style bike, because they find them more comfortable.

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  12. it's still hard to compare because it's not apples versus apples. sure, my DL1 is cushy, more so than any of my other bikes. but it also has a sprung saddle and 40mm wide tires-- neither of which any of my other bikes have. if i had those on my lightweight bikes, would they suddenly become as cushy? possibly. but without doing the experiment, i'll never know, so i can't come to any conclusions about weight correlating with stability.

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  13. Difficult to test because of things like difference in tire clearance. (Though I suspect that you do not really believe yourself it is really a matter of tires and saddle.) And also keep in mind that if one puts 40mm tires and sprung saddles on lightweight bikes, they become heavier...

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  14. agreed, difficult to test, which is why i don't think anyone has done anything like this systematically, which leads to speculation.

    yes, it is true that sprung saddles and wider tires add to weight, but things like steel rims, steel handlebars, steel seatposts, steel fenders, steel racks... these all contribute to weight, too.

    something else to consider in the stability equation is that heavy wheels can contribute to the feeling of stability on a bike independently of other variables such as frame weight, because it's the rotational mass of the wheels that contribute to keeping the bike upright. so it's possible that swapping out the stainless steel rims on the gazelle for lightweight aluminum rims would make the bike feel less stable, even if you compensated for the lost rotational mass by adding the saved weight elsewhere on the bike.

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  15. To a driver, a person on a bike does not look more substantial when riding a roadster vs the lightest bike. It is all the bike rider's perception (?illusion) of a safety difference

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  16. Do most of you commute in Kansas? I've biked non-vintage bikes of various weights on these things called "hills" and yeah, I sorta notice a ten- or fifteen-pound difference between bikes.

    Never mind the difference in effort on the extremes, between a carbon frame on one side and a 50-pound Dutch tank on the other. We're talking 30+ pounds there.

    I'm a little skeptical of the apparent "heaviness" of a traditional city/vintage bike having much to do with drivers taking more care around them. My own guess leans more towards the other factor--the uprightness of the biker makes him or her more visible. And to put it this way, maybe less offensive to your average driver? The typical drops on your typical modern derailleur put the biker in the lower messenger/lycra maniac pose that is so beloved in our culture. But when drivers see someone upright on a Gazelle and the like, the images generated in the reptilian cortex revolve around something closer to Mary Poppins.

    Only a monster would do anything mean to Mary Poppins.

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  17. re anonymous @ 10:40, yes, to tie that to what I said--I don't think it's the weight of a city bike making the rider more substantial--I think it's the upright posture making the rider seem more vulnerable, the opposite. Or more family-neighborhood oriented and less threatening and more in need of help from the driver. More help coming in the form of not running you over.

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  18. It's little wonder that you enjoy the Rivendale mixte over a lighter bike. It has all the right stuff to ensure a comfortable ride whereas a lighter bike will always be about speed.

    Heavy cars have a great ride due to their weight and so it is with bicycles.

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  19. Anon 10:40 - Even if it's an illusion, it is effective at increasing confidence in traffic : ) However, when I am in a car, I myself do notice upright cyclists on large bikes more readily - simply because they are higher.

    Christopher - I so agree about "Mary Poppins"! And I notice also that drivers treat me differently when I am dressed nicely and my hair is loose, then when my hair is tied up and I am dressed more athletically or raggedy. I have been wanting to write about that, actually.

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  20. being slightly facetious maybe you could fill the Royal H's waterbottles with lead shot and see if it makes a discernible difference to handling. You could get about 8kg in each one, im betting you would forget it was there after a while, when riding in flattish terrain anyway.
    There is a precedent for this in the "professional" peloton:
    http://en.wikipedia.org/wiki/Jean_Robic

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  21. samuel chilbolton - I don't think that's such a crazy idea : )

    But I don't think I need to go that far: When I ride the mixte with a huge, heavy bag, I feel more comfortable in traffic than when the bike is "naked".

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  22. regarding reptilean driver psychology, the mary poppins look doesnt suit me but when I drss in 'normal' clothes drivers def give me a wider berth here in UK, especially if im wearing wellies!
    ps - on a slightly pedantic note im looking at the photos of the mixte (beauty!) and thinking maybe you don't have enough clearnace between fender and tyre to be entirely safe. Chris at Velo Orange recommends minimum 8mm, ideally 10-12mm (see: http://support.velo-orange.com/#fendersarticle.html) . I could be wrong but you look to have less than 8mm there.

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  23. I know from experience that a heavier bike (all other factors being equal) will stand up better to potholes and such. Also, they're better on snow and ice, as they provide more traction as long as the tires are good.

    However, I don't think that the weight is as much a factor as the fact that the heavier bikes tend to have wider tires, which give them more traction; longer wheelbases, which make them more stable; and thicker or wider rims and other parts, which tend to absorb shock better.

    Velouria, I also find it interesting that you say, in essence, that riding upright in traffic gives us more respect. I started to notice something like that when I started riding to work in skirts and dress shoes. Perhaps drivers see us as more "ladylike"--which is to say more bourgeois and less countercultural--than when we're hunched over on racing bikes. Think about it: How do drivers, particularly male drivers, see us differently when we're upright than they see us when we're bent over!

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  24. somervillian - Do you have link to that debate by any chance? I would like to take a look at it.

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  25. I completely agree with the statements here about preferring heavier bicycles. One major problem I have run into with my bikes (especially the 28" wheels on the DL-1) is that the wheels are actually too wide and the frame is too long for the bus cycle rack - imagine that! So, unlesss I have a benevolent bus driver who will let me bring my bike onto the bus (anyone tried that?), I can't use the DL-1 on public transport. And because the bike is the approximate size and weight of my car, putting it on a car rack is an equal nightmare. Because of this, I have the Raleighs to thank for the fact that the entire rear portion of my car looks like it was used as a scratching-post for a jaguar.

    So, when it comes to commuting, I find myself wishing I had access to a sturdy (but smaller!) bike that will fit on public transport and in my car without hassle or damage and that still has the "safe" feel that I have come to love and appreciate with my Raleighs. So perhaps this is why I am desperately saving for a Brompton? ;)

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  26. "I also know hard-core roadies who, when it comes to transportation, will ride only a heavy Roadster"

    "Do most of you commute in Kansas?"

    One of the little "secrets" of the "invention" of the mountain bike is that Joe, Gary, Tom and the boys didn't have to go out and acquire their clunkers to bomb Repack. They already had them, because they had already discovered that old heavyweight one speed coaster brake bikes (the term "cruiser" hadn't showed up yet) were better everyday transportation bikes than their lightweight road racers.

    In San Francisco.

    On the flip side at the same time on the opposite coast I failed to invent the XC mountain bike because I was riding single track on my road racing bike and found it perfectly suitable, although I did have a set of 27x1 1/4 wheels for the task (back in the day even an "aggressive" bike like the Teledyne could fit these).

    I'll ride any bike anywhere without giving much thought to the matter, although I suppose mud on a Strida would present serious difficulties.

    I don't find weight in itself to be a virtue, it's just the result of "performance" being measured in terms of durability (and perhaps cost) rather than speed. It doesn't bother me because I'm not racing and yes, if you crack out Ye Olde Newtonian equations and do the math you'll find the speed difference in the city to be a matter of a relatively few ideal seconds, some of which you aren't actually going to achieve in the empirical world and the rest you'll fritter away thoughtlessly by the time you've finished locking your bike.

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  27. This thread explains exactly why I don't like my carbon fiber Trek for commuting: it feels too light. I'm a light rider: (5'8", 125lbs.) and my ideal bike weight seems to be around 20-22 lbs. Less, and the rims are so skinny and the tires so light that they have to have high tire pressures and I'm getting bounced all over the seams and holes in the road. More and I'm lugging it up the hill at the end of the day. So right-sizing for weight for any particular duty seems to be the order of the day. That's why I have a stable. I'm starting to see the value of your Royal H, though. Maybe ONE bike, custom balanced for my riding would be better. OK, maybe two, or three...

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  28. When we Americans rode heavier bikes we sure were skinnier people.

    When loaded with assorted bs my "heavy" bike (40lbs) is often more than half my weight but I love how the cargo doesn't change the way the bike handles at all. I prefer a heavy bike and one that's upright for city riding, so far. I am interested to see how often I want to ride my VO mixte when we build it up.

    I definitely agree with Velouria and Justine: the more formally I am dressed, the nicer drivers are.

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  29. @Velouria: do write about the correlation between appearance and regard by drivers. They treat you different if you look like Mary Poppins than they do if you are dressed like Miss Almira Gulch from the Wizard of Oz? Same bike, different dress.

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  30. V., My experience doesn't gibe with yours. I've found that the stability of the bike is largely determined by the wheelbase The soft ride over potholes and other obstacles is determined by the choice of tires. I don't think I lose any respect from drivers when riding my touring bike. The difference here is the speed travelled. A bike that is really riding with the traffic and keeping up to speed can be a target for drivers who believe that bikes do not belong on the road taking up the lane The riders of heavy commuter bikes generally yield to traffic and drivers nod in approval of the deference.

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  31. lyen: http://lovelybike.blogspot.com/2010/11/heavyweights-middleweights-lightweights.html

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  32. Y'know what's really comfortable - an Easy Racers Tour Easy! loooong wheel base. Of course, it's heavier because it has more frame. Somehow, it's wicked fast anyway.

    Personally, I like a lot of weight. I love putting over 100# of groceries in the trailer. The ride home is a piece of cake. I pedal ~3 times, and momentum does the rest. That's a fairly flat stretch though. On longer trips, I go way faster downhill, and a good bit slower uphill. Overall, I break even.

    Also, being a 300 Pound Gorilla, I have a preference for heavier bikes. I have an absolute need for tires to be at least 35mm wide. Otherwise, I get pinch flats on a daily basis. Also, the difference between 320# (me + carbon racer) and 350# (me + dutch bike) is a gain of less than 10%. Seriously, I'd prob'ly be okay with a 100# bike.

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  33. Anne - I think that wheelbase plays a starring role in it, to be sure. But the reason I don't think it can be solely explained by w-base, tires, etc., is that I've tried bicycles with very similar wheelbases, identical saddles and tires, and have experienced significant differences in ride quality - which I attribute to tubing. As others have said, I think that everything else remaining constant - which of course would be almost impossible to actually accomplish unless I design the frames myself just to experiment on them - the tubing that is more shock absorbent and comfortable tends to be heavier.

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  34. velouria said: "the tubing that is more shock absorbent and comfortable tends to be heavier."

    hmm... i'm not too sure about that...

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  35. why not? the idea is not original to me

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  36. is there a frame builder in the house??? i think we need someone knowledgeable in metallurgy to comment here, because the notion of "shock absorbency" and comfort are very subjective terms, and what one person might call shock absorbency another might call sloppiness or flex. generally speaking, steel flexes and it is the flexing that provides shock absorbency. the term "lightweight" steel is really a misnomer, because steel is steel, and an ounce of hi-ten steel weighs the same as an ounce of reynolds 531. however, since the reynolds is stronger, it can be drawn into thinner and lighter tubes that provide the same strength as thicker hi-ten tubes. the key is to design a frame to be strong enough to be durable and not bend out of alignment from hitting bumps while making it acceptably light and also comfortable, regardless of material used. the thicker and heavier you make the frame--regardless of the material--the less shock absorbent it becomes, but also the stronger it becomes.

    also, wheels make a big difference in shock absorbency. a well-built and properly tensioned wheel will be more comfortable than an under-tensioned or over-tensioned one.

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  37. What Somervillain said. The most common complaint about heavy frames is that they have a "dead" feel to them and don't absorb shocks.

    It's springs that absorb shocks (the things on your car that you call "shocks" aren't; they're dampers).

    Contrary to intuition heavy bikes are typically fitted with softer springs than lighter ones and it's that that can make them feel like they absorb more shock; not the weight of the bike, although the inertial mass with soft springs contributes to the "floaty" feel - Cadillac vs. Ferrari.

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  38. somervillain - Thanks! That calculator is especially useful.

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  39. i wonder if any local frame builders are reading this? ant? royal H? geekhouse? i am fascinated by this topic and would love to hear from a frame builder about choice of steel in terms of tubing thickness, diameter, formulation, etc... and how these all contribute to that elusive characteristic known as "ride quality". all of my speculation (and it really is just that) comes from a background in engineering, and not actually designing and building frames (obviously).

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  40. As much as I want to flatter myself in thinking that framebuilders read my blog daily, I think Friday night might be an exception : ))

    I think Mike Flanigan would be a good person to ask about this, because he works with both the lightweight stuff and hi-ten. Will shoot him an email.

    kfg said...
    "It's springs that absorb shocks...
    Contrary to intuition heavy bikes are typically fitted with softer springs than lighter ones and it's that that can make them feel like they absorb more shock; not the weight of the bike"


    Unless I misunderstand you, this is congruent with what I have been saying. I did not suggest that it is the heaviness in of itself that is shock absorbent, but that heavier tubing tends to have more shock absorbent properties - for whatever reason.

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  41. 300 pound gorilla--that's something I hadn't thought of, the proportion of your own weight to the weight of the bike and how much difference that does or doesn't make. I'm around 143 pounds so with a ballpark swing of 30 pounds between all-carbon and Dutch Tank, that's a 21% difference in the weight I'm lugging around, specifically including uphill.

    Also, I'll note that the 30-pound difference is roughly equivalent to what my loaded Soma smoothie ES weighs (say with a couple of water bottles and a light, tiny under-seat bag). So we're talking about the equivalent of bringing an extra bike along.

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  42. kfg said...
    "It's springs that absorb shocks...
    Contrary to intuition heavy bikes are typically fitted with softer springs than lighter ones and it's that that can make them feel like they absorb more shock; not the weight of the bike"


    kfg-- i'm confused by this. are you referring to cars? i think you are. that's a whole discussion by itself!

    because if you are referring to cars, i agree 100%. large german cars typically have very stiff springs, and have a very stiff ride, despite their heavy weight. by contrast, crown victorias are very softly sprung, so that the frost-top driving it doesn't muss her perm when she runs over the cyclist. ;-)

    so it's not the weight of the car, per se, that dictates how softly it will ride. it's all about the springs. on a bike, the tires, wheels, fork, frame and saddle are all part of the collective "spring". the role of the frame in this multi-component equation may or may not be instrumental, but more mass in the frame does not equate with more contribution to "spring".

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  43. Hey, I love the way old large German cars ride! My first car was an old Mercedes and it handled like a pile of bricks - in a good way. By contrast, Crown Victorias make me car-sick.

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  44. "Unless I misunderstand you . . ."

    You do. The heavier tubing is less springy, thus absorbs less shock. This is basic engineering. To increase the rate of a spring, make it thicker.

    This is assuming the same material and thus the same Young's Modulus; i.e. we're not going into the carbony bits here.

    Fitting springs with a lower rate to the less springy frame compensates for and masks the loss of spring in the frame.

    If you want to try out some shock absorby goodness go out and find the lightest chrome-moly rigid mountain bike frame you can (they be cheap as the dirt they're covered in) and fit it with 3.0 Schwable Big Apples at 20 pounds.

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  45. Okay, I get it now. I have no background in engineering and only very limited experience working with metals.

    So, question: How do you explain how cushy the traditional Dutch and Roadster-style bikes feel in comparison to lighter upright bikes with the same tires and similar geometry?

    Also, why have I heard from several industry sources at this point that hi-ten "feels more comfortable" when done right?

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  46. "i'm confused by this. are you referring to cars?"

    No, although I am being a bit deliberately obtuse as a rhetorical tool (one of my nasty habits) and using cars as an analogy for a closer may have made the issue more obtuse than I intended.

    I miss the shit out of my old 280. On hard, skinny economy tires it had no grip to speak of, and yet you could drive it completely crossed up with one hand while drinking coffee in complete control. What a car.

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  47. I don't know so much about the physics of bike frames but im going to chip in anyway! I do have empirical experience of lightweight steel alloys being much "springier" eg If the bike is stationary and you stand hard on one of the pedals it is possible to see the frame flex in the opposite direction, similarly one can see the chainstays flex outwards when applying the brakes on a stationary bike (esp with V-brakes). My primitive understanding is that the best steel alloys are Tough ie they can withstand deflection under load without permanent deformation, whereas cheaper steels are stiffer initially but will snap under smaller forces, hence need to be thicker wall thickness of tubeage to construct a bicycle. Could it be that yer basic high tensile steel is better at absorbing high frequency vibrations (eg a new but rough metalled road) whereas a lightweight cromo/cromang frame will transmit high frequencies to the rider but can absorb low frequency shocks just as well as the much heavier hi-ten? In my experiencde it is high frequency vibrations that cause fatigue when riding because arm and leg muscles are not well adapted to absorbing them, but they are adapted to absorbing bigger low frequency hits (eg riding over a bump). Framebuilders' professional verdicts eagerly anticipated!

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  48. "very limited experience working with metals."

    It doesn't apply only to metals. It applies to any material. Gibbon's Decline and Fall of the Roman Empire is stiffer than a Spiderman comic book.

    "How do you explain how cushy the traditional Dutch and Roadster-style bikes feel"

    The larger inertial mass resists moving more when it hits a bump, so the springs have to move more instead.

    "I heard from several industry sources at this point that hi-ten "feels more comfortable" when done right?"

    You may have noted that on several occasions on your blog I have taken a bit of umbrage when someone has referred to hi-ten as "low quality." It isn't low quality, it's different quality and if you use it "right" it can indeed produce some lovely results. The next frame I build will almost certainly contain a good deal of hi-ten.

    It isn't just absorbing a shock that matters, it's what you do with it after you've absorbed it. It doesn't just go away by itself. That's why cars have dampers as well as springs. Add to that the fact that "feel" isn't strictly mechanical. It's biomechanical and psychological as well.

    Chrome-moly isn't just stronger than hi-ten, it's harder as well. Glass makes an excellent transmitter of high frequency vibrations, felted wool a poor one.

    You can "tune" a frame by mixing various materials of various shapes and gauges and hi-ten has a place in that; but now we're going into the area where frame building becomes less engineering and more black art.

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  49. Holy cross-post, Batman!

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  50. kfg said "If you want to try out some shock absorby goodness go out and find the lightest chrome-moly rigid mountain bike frame you can (they be cheap as the dirt they're covered in) and fit it with 3.0 Schwable Big Apples at 20 pounds."

    or how about a 80s cannondale aluminum rigid mtb, advertised as the most rigid production bike of all time (no shock absorbency there!), and clad it with 2.0" schwalbe land cruisers... rides like a cadillac. this is my wife's bike.

    oh, and kfg, if you can find me one of those chromoly rigid mtbs in my size, i'll gladly send you a box of premium certified dirt in return!

    velouria: i have no good explanation as to why traditional upright bikes like dutch bikes or roadsters ride the way they do. perhaps the loop frame geometry provides some built-in shock absorbency, as perhaps does the long, curved fork... there could be dozens of reasons... one thing that struck me on my ride home from work was how, on an upright bike, very little weight is placed on the hands. the majority of body weight is placed on the saddle and pedals. the knees are natural shock absorbers when bent, and the saddle is another major shock absorber (as is the glutius maximus!). however, the handlebars are *not* very good shock absorbers. when i ride my more agressive bikes, thereby placing more of my body weight on the bars, more road shock is transmitted *through* my hands. that could be a big part of the difference in overall comfort observed on traditional upright bikes.

    samual chilboton: i like your hypothesis... interesting. it would indeed be nice for a frame builder to chime in and answer some of these bewildering questions.

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  51. Wow, this is making my head spin ;)

    Yes, it is late Friday night, but I am working and do not have time to write a thoughtful response.

    I do read your blog everyday, however I often do not read the comments, because I do not have that kind of time to spend [but the comments are good].

    However I did build a Dutch style Roadster last week [class bike]. It had 66o angles, 60mm fork rake, 475mm chainstays, 700 x 50mm tires and was built in the big roadster style. We used semi-light 4130 butted tubing[9/6/9mm] and custom made lugs. 8 speed coaster brake and it came out to 37 lbs [no lights or racks]

    This bike rode very nice, stable, no hands riding [for me anyway] and very smooth.

    A similar Roadster bike like a Pashley, Azor etc... would weigh in around 50 to 55 lbs.

    Most of the fully equipped bikes I build weigh in at 40 lbs

    I am kind of rambling here [long day/week]...so I think that a heavy bike is good to ride, along with big tires, long wheelbase, upright position etc...however a Roadster made of Hi-ten steel or low carbon steel will never be a strong as a Roadster bike made of 4130 tubing [even if it is lighter]. The only reason these euro roadsters are made of HiTen or low carbon steel is to keep the price down.

    I think once you get above 35 lbs the bike will have the heavy smooth feel, but only if it also has the Dutch geometry, wheelbase, wide tires etc...

    Maybe I can write more about this later, but I need to get back to work.

    Maybe you guys should go down to Rebones and have some wiskey ;)

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  52. A loop frame will ride springier because the lack of a top tube per se means less triangulation in the front part of the frame. The curved tube on loop frame will act much like a leaf spring. Even a straight tube on step through will have the same effect, but not as pronounced. A relaxed fork angle puts more leverage on the fork which results in more flex.

    I've probably over-simplified a bit, but an easy way to see this (easier than me fumbling along trying to describe it!) is to have a helper stand on the pedals and bounce up and down while you watch from the side. You should be able to see how the front end on a loop frame flexes much more than a diamond frame.

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  53. "kfg, if you can find me one of those chromoly rigid mtbs in my size, i'll gladly send you a box of premium certified dirt in return!"

    Boston seems to be full up of old Raleighs. The Adirondacks, on the other hand, are full up of old mountain bikes. Of such things are trade made.

    However, dirt may be cheap, but shipping is expensive; and we've got plenty of frickin' dirt.

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  54. Thanks for commenting Mike : )

    In defense of the loitering - I think that some of us post here precisely because we are working. When you are chained to the computer, this kind of stuff is really the only viable way to take short breaks. But I do think that some of these debates (in which I myself participate) are a bit pointless, given our lack of background in this stuff. Speculation only breeds rumor. If we really want to know, we can do some basic research on framebuilding and metallurgy.

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  55. velouria said "But I do think that some of these debates (in which I myself participate) are a bit pointless, given our lack of background in this stuff. Speculation only breeds rumor. "

    true, and i'm as guilty as anyone here for speculating about these things. but the topics you choose to blog about (this one being a perfect example) invite exactly such speculation and debate... especially when you know that there are dichotomous "camps" of thought on these topics.

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  56. Here's the science :-)

    http://www.bmj.com/content/341/bmj.c6801.full

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  57. Here's a BBC article about the same science:

    http://www.bbc.co.uk/news/health-11958903

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  58. I feel more confident on a lighter (mountain bike), whether on or off road. I find the lighter frame gives more strength and is easier to control. Not to mention requiring much less energy. I never used to be so picky until I replaced a steel bike with a an aluminium one; the difference was amazing and suddenly commutes turned into a more pleasurable experience.

    One thing I suggest if you don't feel as confident on a lighter bike..see if you can use thicker tyres, eg off-road. The roads here in the UK are often really terrible, what with the traffic density and number of heavy vehicles. It's as bad being a British road as it is on a British trail, so what I do is use a light bike but also ensure I am using thick, nobbly tyres. It adds a lot of confidence and improves the feel (well that's the way I feel about it anyway). I once had to replace the off-road tyres with semi-slick one's and felt a lot less confident.

    Happy trails :)

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  59. Velouria, I see nothing wrong with taking such breaks, in fact I actively encourage it. Everyone knows that after a set period most people get fatigue and lose concentration. There is also EU legislation that states you are allowed a break every so often. Maybe being on the screen isn't the best way of taking a break but at least it gives the mind a bit of a breather. I wouldn't expect my staff to be chained to one screen all day, that's inhumane.

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  60. I am in general agreement with the article. I don't find that a bike's weight makes a huge difference when I'm riding though, with two exceptions; going up hills when a light MTB is definitely less difficult, and going downhill on rocky trails when heavy and solid is a real lifesaver.
    A note regarding bike weight though, It's all very well to drool over the latest carbon fibre and titanium rocket bike weighing in at 7 kg when one's wallet will only stretch to 13kg but it may be better to loose 6 kg of extra weight. And a whole lot less expensive in so many ways.

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