View Full Version : High Performance Urban Bike Suggestions
Hi,
I'm in the market for a high performance folder and would like your opinions and advice. I have been eyeing the Dahon Speed Pro TT for a while. It rides really quick and agile and looks amazing. I've been looking at recumbent trikes as well, but portability is a big criterion.
My intentions are to ride to work (with some possible public transportation) as well as long distances on the weekends. Do you have any suggestions on similar models or bad experiences with the Pro TT?
Your input would be greatly appreciated!
invisiblehand
06-19-08, 10:40 AM
My experiences with public transportation would pretty much exclude the use of 20" folding bikes on a subway/metro system.
With the understanding that I have never ridden a Bike Friday tikit, that is probably the bike you are looking for ... http://www.bikefriday.com/tikit/robspinkone
You can ask PM124 about his Birdy too.
There are people that seem to get a lot out of a Brompton/Merc. But the bike isn't a performance bike in my opinion.
From my experience, best all-around performer is birdy. Its folded size is almost as small as brompton, and with some tune-ups (better drivetrain, stelvio tires, etc) you can even do some century riding with your friends without much problem.
My experiences with public transportation would pretty much exclude the use of 20" folding bikes on a subway/metro system.
+1
There are people that seem to get a lot out of a Brompton/Merc. But the bike isn't a performance bike in my opinion.
+1
Hey,
Thanks for your responses! I like the bikefridays -a little above my price range though (tikits or pocket rockets are pushing $2500+). How do they compare with the Pro TT? I'm told the number of speeds on the TT edge out it's competitors in the same price bracket. Or is there a huge performance difference between 16 and 24 speeds?
invisiblehand
06-19-08, 11:30 AM
Hey,
Thanks for your responses! I like the bikefridays -a little above my price range though (tikits or pocket rockets are pushing $2500+). How do they compare with the Pro TT? I'm told the number of speeds on the TT edge out it's competitors in the same price bracket. Or is there a huge performance difference between 16 and 24 speeds?
Let's see ... I don't have their brochure handy. But there are tikits with the SRAM Dual Drive. Check their website for a price. My guess is $1500.
Dynocoaster
06-19-08, 12:31 PM
They have Tikits starting at $999 and someone was saying that Gaelans has upgrades.
http://www.bikefriday.com/
My experiences with public transportation would pretty much exclude the use of 20" folding bikes on a subway/metro system.
With the understanding that I have never ridden a Bike Friday tikit, that is probably the bike you are looking for ... http://www.bikefriday.com/tikit/robspinkone
You can ask PM124 about his Birdy too.
There are people that seem to get a lot out of a Brompton/Merc. But the bike isn't a performance bike in my opinion.
Invisiblehand - what city do you live in? I've contacted my city transportation department and they say there are no guarantees that the driver will allow a folded bike on the bus. Yet I've seen people haul huge pieces of luggage or even little carts. Talk about forward thinking...
folder fanatic
06-19-08, 03:09 PM
Invisiblehand - what city do you live in? I've contacted my city transportation department and they say there are no guarantees that the driver will allow a folded bike on the bus. Yet I've seen people haul huge pieces of luggage or even little carts. Talk about forward thinking...
I hope you don't mind me chiming in, QVD, but I thought I can answer your questions and concerns. I live in the Southern Califonia area, right in the middle of the urban part. I take my folders on the bus or train, but with a difference. I always cover them BEFORE I board, or even the bus/train is in view. I use all sorts of bags/slipcovers. You can see many examples of them on my Flickr Website World Of Folding Bicycles below. I even include a pattern and instructions on making your own very simple bag to cover your bike. You are experiencing "bike prejudice" in full bloom. I always pass my own folders off as luggage except for "Bike To Work Day" when I purposely keep them uncovered. On that day only I use them as a free pass for many of the bus/train lines surrounding my house.
QVD - I suggest you just bite the bullet and bike everywhere! Who needs public transportation when you have a bike?!?
invisiblehand
06-19-08, 04:04 PM
Invisiblehand - what city do you live in? I've contacted my city transportation department and they say there are no guarantees that the driver will allow a folded bike on the bus. Yet I've seen people haul huge pieces of luggage or even little carts. Talk about forward thinking...
I live near Washington DC.
Metro rules allow folding bikes onto trains unencumbered during off peak hours and in a bag during peak hours. I forget the rules for buses. But I believe that with large packages that a bus driver and prevent anyone from coming aboard.
That said, a bike in a bag will rarely provoke a response.
I'm starting to think it is "bike prejudice"! The rules are similar in my city -bikes are allowed on subways, but off peak-hours, which is when I'd use it..and driver's discretion for buses.
Thanks, folder fanatic, I guess I'll become that guy on the bus with the huge piece of luggage.
I think the Swift should be a contender. People love to mention it doesn't fold small but that is from a side perspective. From above is is quite small once folded. If you got a bag cover for it and folded it, the bag while big from a side perspective, would be skinny and not occupy a lot of floor space.
Plus it is one of the best performance folder out there. Check my sig. I have done very long rides, fast rides and hard climb rides on mine.
Mr. Smith
06-19-08, 06:49 PM
Invisiblehand - what city do you live in? I've contacted my city transportation department and they say there are no guarantees that the driver will allow a folded bike on the bus. Yet I've seen people haul huge pieces of luggage or even little carts. Talk about forward thinking...
Most won't allow bikes of any kind during peak hours. If you can disguise it properly, you can take it on. The most successful bike to get on subways I've seen is a Strida (excluding the silly ones from Mobiky and CarryMe), but it's hardly high performance. I'd spring for the tikit for $999. "Performance" folders aren't really right for this application. Get small, solid, and convenient. As a daily commuter on a folder, it beats up a bike pretty hard to use it every day on a longish ride and fold it 4-6 times a day. A hub gear and built like a tank should be your first and foremost requirements. You're going to beat the s##$ out of this thing commuting.
SesameCrunch
06-19-08, 06:56 PM
I had a SpeedPro (not the TT, tho). I got it for the same reason you are looking at - to be a high performance bike that would be easily transportable. Truth be told, I was disappointed in its performance and I eventually sold it.
The steel frame and SRAM DualDrive make it too heavy to be a "performance" bike. I found myself lagging behind in the hills all the time, when I'm usually in front in my road bikes. I eventually bought a used Dahon Helios 20th anniversary edition which weighs in at 17lbs. Now, I'm back in the front on hills when I ride it with my group.
http://i39.photobucket.com/albums/e157/sesamecrunch/Dahonsm2.jpg
I have no criticisms of the bike otherwise. It's a solid bike. Just don't expect to be as fast as you normally are.
yangmusa
06-19-08, 07:36 PM
I have a Birdy, though I've had it barely two weeks and only have 50-100 miles on it so far. First impressions are that it's pretty fast, and certainly a lot more comfortable than my Swift was. But - the big disclaimer here would be that the streets of SF are shockingly bad. I imagine that the Swift is probably faster on smooth roads, but round here that doesn't happen much.
I'll probably write more about the Birdy when I've got more time in the saddle.
(...) I eventually bought a used Dahon Helios 20th anniversary edition which weighs in at 17lbs. Now, I'm back in the front on hills when I ride it with my group.
Nice ride Sesame! :)
I had those clip-on drop bars for a while too, it was a good setup.
makeinu
06-20-08, 07:55 AM
The most successful bike to get on subways I've seen is a Strida (excluding the silly ones from Mobiky and CarryMe), but it's hardly high performance.
Please, can't we get over the small wheel bias? This is the folding bike forum for Christ's sake.
It's been well established that the Strida is the most ridiculous bike in existence. That's not to say there's anything wrong with the Strida, but at least the Mobiky and Carryme the standard U-shaped folding bike geometries.
SesameCrunch
06-20-08, 08:28 AM
It's been well established that the Strida is the most ridiculous bike in existence.
Excuuuuse me!
You and what other biking god established this fact?
trueno92
06-20-08, 08:47 AM
i can testify that its hardly a performance bike. It takes the legs like pistons to get the thing over 20km/h and then you look like a crystal meth addicted circus performer runaway.
I love mine to death but as a performance bike? Unless this idea of performance is folding up and riding a packed subway with ease, then sure. If its anything to do with riding on the road, even a more aggressive tucked riding position is difficult to maintain without bar-ends, or maybe bullhorns... and even then, ur only doing 20km/h!
until i can figure out how to get a duospeed hub or save my pennies for a schumpf speed drive.. i don't think its gonna happen..
someone in asia has made it into a performance folding e-bike tho
unfortunately tho, this was the only pic i found of it..
http://farm1.static.flickr.com/47/110796725_7143a5f3e9.jpg?v=0
geo8rge
06-20-08, 10:37 AM
decide on tire size - you want probably want 20" or slightly smaller Birdy.
Decide on drive train - I suggest a 3 speed, although single speed, or newer 8 speed internally geared hubs might work to. I advise against a derailer bike. too much maintenance for a commuting bike.
Once you know wheel size and drive there will be only a few bikes to choose from.
makeinu
06-20-08, 10:57 AM
Excuuuuse me!
You and what other biking god established this fact?
Being the most ridiculous person in existence I believe I have the authority to be the judge of all ridiculousness. :twitchy:
It's a perfectly good bike mind you, but there's no denying that it's nutty.
SesameCrunch
06-20-08, 12:25 PM
Being the most ridiculous person in existence I believe I have the authority to be the judge of all ridiculousness. :twitchy:
It's a perfectly good bike mind you, but there's no denying that it's nutty.
OK, I'll buy that last characterization :roflmao2:.
But I loves my Strida :love:, nutty as it is.
So QVD - what have you decided on?
So QVD - what have you decided on?
I'm not sure, though I've narrowed it down to a Pro TT or Pocket Rocket. Have you decided? It appears you need a bike that's as capable to ride in Europe as it is in, say, Edmonton.
xcontext
06-22-08, 10:03 PM
I ride a Brompton SL2-X all the time to L.A. I bring it to Metrolink, Red Line Metro, Blue line, I ride it through potholes downtown Los Angeles. I alternate between it and a cyclocross bike. I would not dare to take my road bike yet the Brompton does just fine--takes the abuse with almost no maintenance. If it is fitted right it can perform. People rode some amazing races on those. The S means flat bars which give more sporty position. The X means it has some titanium bits that make it lighter (not by so much). That is the only folder I have so I can't compare--just offering an opinion (and that is all it is) on a Brompton.
nekohime
06-22-08, 10:50 PM
The Dahon MuSL is all sorts of awesome... tried v6v6v6's one during the SoCal foldies ride and I went ZOOM!!!! It's very light too--I could easily carry it up and down the subway stairs if need be.
Whatever folder you buy, do go with Folderfanatic's advice about the bags so that you can bring it on the bus/train/whatever. I've had bike prejudice too--I was trying to get on a completely empty bus, and I told the driver I was only going a short while, but he still said no, put that darn thing on the rack. Another way to be able to bring it on the bus is to befriend the bus drivers who you usually ride with--my morning commute is always with the same bus driver, who lets me put the bike wherever I want.
Dynocoaster
06-22-08, 11:01 PM
If price isnt a problem the Limited edition Dahon sounds pretty nice and very light.
http://www.thorusa.com/dahon/2008/muxxv.htm
Thanks for the suggestions. My budget is around $1500CDN so that eliminates the special edition Dahon, and most of the recommended Bike Fridays.
I want a fast bike, but how much extra will weight affect performance? Will a few pounds be the difference between 2, 5 or 10kph? This is mainly a commute bike, so I won't be givin 'er all the time, but just want to know its capable when I do push it.
Thanks for the suggestions. My budget is around $1500CDN so that eliminates the special edition Dahon, and most of the recommended Bike Fridays.
I want a fast bike, but how much extra will weight affect performance? Will a few pounds be the difference between 2, 5 or 10kph? This is mainly a commute bike, so I won't be givin 'er all the time, but just want to know its capable when I do push it.
On a flat surface, the difference between a 15 pound bike and a 25 pound bike will be 0.000001 Km/h. Seriously, it will be a teeny tiny fraction of a difference at all. On the other hand, if you are climbing a steep hill, it really will make a difference to lug around the extra 10 pounds. Much more important is how far forward you are leaning. (That is why recumbents can go so fast on flats.) The other thing that will make a dent is your tires. If you have thick tires that are heavily puncture resistant, you might lose 1/2Km/h on a really smooth surface relative to a racing tire.
One or two professionals have posted on the Birdy forum suggesting that they are faster on their Birdy than on their road bike (e.g., http://osdir.com/ml/culture.bicycle.birdybike.general/2000-01/msg00028.html). I'm sure that this has to do with variation in the surfaces they are riding on.
As for me, I keep up with the $5000 Litespeed riding guys in tight shorts and team jerseys just fine until we get out of the city and into the hills. That's partly b/c I'm too cheap to lighten my bike by the extra 2Kg it has yet to go. Someone on the Birdy forum is selling an 8kg bike, but I won't be the one buying it.
Of course, the biggest factor is how fit you are.
Of course, the biggest factor is how fit you are.
+1
What would be better spent, $1000 to improve your bike by making it lighter, or a week unpaid leave spent training?
Thanks for the info -I had previously thought it was a substantial performance difference, given how much weight is stressed in the posts comparing folder specs.
Now that I've got that out of the way, the next big criteria is quality/maintenance. I've heard more issues with the Pro TT than the Pocket Rocket (or any BF, for that matter). Can anyone provide insight from their experiences?
Much thanks again.
Mr. Smith
06-24-08, 12:07 AM
Thanks for the suggestions. My budget is around $1500CDN so that eliminates the special edition Dahon, and most of the recommended Bike Fridays.
I want a fast bike, but how much extra will weight affect performance? Will a few pounds be the difference between 2, 5 or 10kph? This is mainly a commute bike, so I won't be givin 'er all the time, but just want to know its capable when I do push it.
You really should try out a tikit. It's in your price range (last I checked US$ to CDN$ = 1:1) and a good balance of practicality and performance. Get the 9 speed express tikit with drop bars and you'll be set. I really enjoy the flip and fly aspect without messing with seat post heights or whatnot.
The difference in build quality and design between my Birdy and my previous Dahon are huge. Bike Friday is also hand built, and Bromptons seem to hold up extremely well as well. The older Tikit I tried had a very flexy stem, but I think that they've fixed that now.
I would decide if you want suspension (or put up with big tires), a compact fold (Dahon, Brompton, Birdy), a quick fold (Tikit, Swift), etc.
makeinu
06-24-08, 09:31 AM
Thanks for the info -I had previously thought it was a substantial performance difference, given how much weight is stressed in the posts comparing folder specs.
Weight makes a huge difference once the bike is folded and you have to carry it. It's less important while riding because you have gears to give you leverage (though it can still be important if you have to stop often or go up hills....people around here like to talk about how weight doesn't matter much when riding on an open flat road, but I've never seen such circumstances in the real world).
Dynocoaster
06-24-08, 09:54 AM
Where are you located in Canada?
Dynocoaster
06-24-08, 09:58 AM
+1
What would be better spent, $1000 to improve your bike by making it lighter, or a week unpaid leave spent training?
Get a physical and a physician approval before training especially if there is heart concerns in your family lineage.
Dyno: I'm in Edmonton, Alberta -it's relatively flat here with minimal wind. This
was supposed to add to my training as I run 25-30km a week.
PM: No suspension required (I would imagine it would hamper the speed), compact to the point where I can lug it onto a bus without trouble and folding speed is not really a concern, although I've read the TT's kinetix handlebars do hinder the size.
Here's a dumb question: does folding frequency affect the bike in any way, other than getting scratches and dents?
Mr. Smith: I've looked at the tikit as well and am focusing on BF's line now, mainly because its custom fitting and hand built features. Thanks for all your input!
Dynocoaster
06-24-08, 11:38 AM
Folding shouldnt affect anything as long as the hinge is lubed as for scratches , I would use a bag.
Here's a dumb question: does folding frequency affect the bike in any way, other than getting scratches and dents?
It's not a dumb question. Answer is, it really depends on the bike. The old U-shaped folders, I mean the German, Dutch, Italian, French, Czech, &c ones, had a hinge system that would eventually wear out. The Raleigh Twenty, though generally similar, had a much better hinge system that is as close to indestructible as a bike component can be. Folding a Strida doesn't cause any wear, but you can break the plastic socket at the top of the steerer (and I've done this twice). I'm told this is because I bent it too far one way or another; I dunno. Folding my Downtube Mini (somewhere under a thousand times) has caused no wear that I've noticed. I don't know about the rest of the folders out there.
QVD, have you excluded the Downtube Mini from your consideration? Seems to me once you have it set up the way you want it, it can be as performance oriented as its rider. There are more expensive bikes out there, of course, but I'm not convinced they offer benefit at all, let alone a benefit commensurate with the price increase.
makeinu
06-24-08, 12:30 PM
PM: No suspension required (I would imagine it would hamper the speed), compact to the point where I can lug it onto a bus without trouble and folding speed is not really a concern, although I've read the TT's kinetix handlebars do hinder the size.
All the folders generally touted as "high performance" will be way too big to take on a bus without trouble. I think anyone would be hard pressed to say that lugging anything larger than a Tikit onto a bus isn't a lot of trouble.
QVD, have you excluded the Downtube Mini from your consideration? Seems to me once you have it set up the way you want it, it can be as performance oriented as its rider. There are more expensive bikes out there, of course, but I'm not convinced they offer benefit at all, let alone a benefit commensurate with the price increase.
No, I haven't. My brother is getting one so I'll wait for his opinion on it. My selection process has been naively influenced by the early approach to car design: if it looks fast, chances are it'll go fast..
Weight makes a huge difference once the bike is folded and you have to carry it. It's less important while riding because you have gears to give you leverage (though it can still be important if you have to stop often or go up hills....people around here like to talk about how weight doesn't matter much when riding on an open flat road, but I've never seen such circumstances in the real world).
It's not subjective experience or talk. It's calculable physics, not religion.
http://www.biketechreview.com/archive/wheel_theory.htm
All the folders generally touted as "high performance" will be way too big to take on a bus without trouble. I think anyone would be hard pressed to say that lugging anything larger than a Tikit onto a bus isn't a lot of trouble.
Don't want to hound you, but a Tikit is one of the largest bikes out there when folded. I take my "high performance" Birdy on the bus here in NYC, which has to be one of the worst places for it.
PM: No suspension required (I would imagine it would hamper the speed), compact to the point where I can lug it onto a bus without trouble and folding speed is not really a concern, although I've read the TT's kinetix handlebars do hinder the size.
Here's a dumb question: does folding frequency affect the bike in any way, other than getting scratches and dents?
Suspension will help the speed on a flat, but uneven surface if the bike is ridden properly (on the saddle with a good circular motion to the pedals). The reason is that road imperfections push back at the wheels, increasing rolling resistance. Adding suspension greatly reduces rolling resistance over the long haul. But it does sap your energy when climbing because it's very difficult not to bob and you are going slower (so rolling resistance doesn't matter much). I think I'm faster on my bike than a road bike in part b/c the small suspended wheels roll well over the lousy NYC streets. Google Moulton and see what he has to say about this.
Regarding folding frequency, not a dumb question at all. Brake cables can get kinked, things can get knocked out of place, dirt can get caught between the seatpost and the inside of the seat stay. Dahons, the Swift, and the Tikit probably fold with the fewest problems, though I've only owned a Dahon. I would say that this is the Birdy's biggest weakness. If you aren't paying attention, you can easily wrap the chain around the rear derailleur and muck up your fingers trying to get it unwrapped.
makeinu
06-24-08, 08:52 PM
It's not subjective experience or talk. It's calculable physics, not religion.
http://www.biketechreview.com/archive/wheel_theory.htm
If you think it's so objective then why don't you try to interpret it? As stated the article "quantif[ies] the effect your wheels have on the average power required to complete a given ride/race", but the relevance of the average power as defined is not addressed.
For a recreational rider the average power is relevant only as far as it is an accurate proxy for the subjective feeling of speed.
For a utilitarian cyclist the average power is relevant only as far as it is an accurate proxy for the subjective feeling of fatigue.
For a racing cyclist the average power is relevant only as far as the power producing resources of the body can be translated to power at the pedals.
So, looking at the article, we see figures like 237.2 watts and 236.3 watts, but what do they mean? Is it always (or even ever true) that a racer can in practice produce 236.3 watts more easily than 237.2 watts regardless of related factors? For example obviously a racer cannot produce a single instantaneous impulse of power followed by an interval of zero power which averages to 236.3 watts more easily than a constant 237.2 watts over the same interval. Likewise, does producing 236.3 watts correspond to a bigger or smaller sensation of fatigue than producing 237.2 watts?
For an engine with well defined operating characteristics (output impedance, etc) some of these questions are easy to answer, but in the case of the body the answer is not so clear and you certainly won't find it by Newtonian analysis.
Aren't you a doctor? If so then I have to say I'm very surprised to see you taking this position. In my experience the problem with physicists is that they think all physically possible scenarios are realistic scenarios. For example physicists generally neglect things like the fact that in NYC a destination next door may really be a four block cab ride because although driving down a one way street is physically possible it isn't realistic; Or that a cyclist may need to muster 2, or 10, or 100 watts of power to put 1 watt into the pedal depending on required waveform of the energy. Doctors, on the other hand, tend to think that only realistic scenarios are possible (ie only situations which have been empirically observed), which is usually more correct, but the problem with doctors is that they often fail to quantify such scenarios.
As the article correctly states, "Sir Isaac Newton proposed his second law of motion nearly 350 years ago. This law elegantly describes the behavior of many systems, bicycles included", but not their riders. This isn't to say that behavior of the combined bicycle/rider system does not obey physical laws. They behave the laws of thermodynamics among others, but not Newton's laws of mechanics.
In short, calculable as it is, the idea that the Newtonian analysis presented in that article somehow refutes the obvious empirical fact that weight makes a big difference to a bicycle rider is simply wrong. There are many things which Newton's laws do not describe. They don't describe electricity, they don't describe cooking recipes, and they don't describe biochemical power transfer. Period. The shame of it is that people fall for it when someone throws around Newtons laws along with some numbers and mathematical manipulations, no matter how inappropriate and inapplicable. If I posted an analysis of the expansion/contraction of a pizza pan "proving" that my recipe for deep dish pizza were superior then people would believe it because they would perceive it to be "scientific", regardless of the fact that the taste of the pizza has absolutely nothing to do with the expansion/contraction of the pan. That's what's happening here.
Don't want to hound you, but a Tikit is one of the largest bikes out there when folded. I take my "high performance" Birdy on the bus here in NYC, which has to be one of the worst places for it.
Fair enough. I have to admit that I haven't tried a Birdy. I've heard from David Lam that it's about the size of a Tikit, which struck me as more petite than most 20" folders when I tested it.
Bicycle weight does not affect its performance if a) the rider are riding at a flat course. b)the rider are keeping a constant speed. But they are too big ifs and in real situation we have to stop and accellerate at times, even if there are no hills
.
And folding bicycles are meant to be folded and carried, where weight matters a lot.
invisiblehand
06-25-08, 09:44 AM
Thanks for the info -I had previously thought it was a substantial performance difference, given how much weight is stressed in the posts comparing folder specs.
Now that I've got that out of the way, the next big criteria is quality/maintenance. I've heard more issues with the Pro TT than the Pocket Rocket (or any BF, for that matter). Can anyone provide insight from their experiences?
Much thanks again.
I think that in practice, weight will only matter while climbing. But skip a cheeseburger every now and then and save some money to get the same effect. EDIT: I am just referring to the performance issue. Of course, weight matters when picking up the bike.
My NWT is pretty straightforward maintenance-wise. Expect to be more concerned about the headset relative to a regular road bike. Every once in a while you should take a look at the rear hinge.
makeinu
06-25-08, 10:03 AM
I think that in practice, weight will only matter while climbing. But skip a cheeseburger every now and then and save some money to get the same effect.
Theoretical considerations aside, can you honestly say you don't feel a difference between riding a heavy bike and a light bike when you ride?
Also, not all of us can or should lose body weight.
Aren't you a doctor? If so then I have to say I'm very surprised to see you taking this position. In my experience the problem with physicists is that they think all physically possible scenarios are realistic scenarios. For example physicists generally neglect things like the fact that in NYC a destination next door may really be a four block cab ride because although driving down a one way street is physically possible it isn't realistic; Or that a cyclist may need to muster 2, or 10, or 100 watts of power to put 1 watt into the pedal depending on required waveform of the energy. Doctors, on the other hand, tend to think that only realistic scenarios are possible (ie only situations which have been empirically observed), which is usually more correct, but the problem with doctors is that they often fail to quantify such scenarios.
As the article correctly states, "Sir Isaac Newton proposed his second law of motion nearly 350 years ago. This law elegantly describes the behavior of many systems, bicycles included", but not their riders. This isn't to say that behavior of the combined bicycle/rider system does not obey physical laws. They behave the laws of thermodynamics among others, but not Newton's laws of mechanics.
In short, calculable as it is, the idea that the Newtonian analysis presented in that article somehow refutes the obvious empirical fact that weight makes a big difference to a bicycle rider is simply wrong.
I am a doctor with only the MCAT section and a year of physics behind me. Moreover, I'm a researcher in the psychosocial aspects of health. So, I guess you've got me there.
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