I was asked this question by a DF rando and although I have some ideas I couldn't really come up with an answer I was 100% satisfied with. Okay we all seem to agree there are fast bents and fast bent riders. How come bents don't hold any overall course records on PBP? On the face of it you have to think PBP is a very bent friendly event:
- you can ride any bent you like including velomobiles or fully faired bents like the F-40
- the course is rolling with no really steep climbs
- the course is long so the comfort advantage should favour bents
- average speeds are high so the bent aero advantage should kick in nicely
- the race is in Europe where fast bents are popular and there is a decent pool of bent riders
- loads of fast bent riders come from all over the world
- you aren't racing professional DF racers
I'd be interested to hear your thoughts.
25 comments:
I post here a slightly edited version I posted on "Tough Love" already, so in case someone hasn't read my previous comments still can follow me:
Let's find out why this is so that so many claim non-DFs are faster, and in some cases it's not true, which I won't deny, you point of climbing a mountain fast likely a recumbent will be slower compared to a DF.
For sake of the discussion, let's treat DF as a model of a bicycle, as short-, long-, and lowrider as models as well.
When you look DF as a model, you see the whole body is able to push on the pedals - and the hands can pull on the steering bar - no other model you can do this, you can pull on the steering bar, but since the other models you sit or lay down, you cannot use your own body weight to push by swinging your body from left to right and back. So, we loose the advantage of the body weight for the other models, as you apply the force horizontally to the pedals, and the gravity of the body weight not helping the same direction. Maybe someone good in physics can already calculate this handicap, we may this apply this handicap for fast climbing, as well fast riding.
The aerodynamics is in favour of the non-DF, we agree there of course.
My premature conclusion is, peak application of force, like a race, a DF gives advantages, the swinging body and it's gravitational force applied direct on the pedals - non-DF don't provide this. Now, we would have to make several graphs, show how good the force of the leg can be applied on the pedals, on non-DF more ideal I would say, but DF at higher stress/force application with a swinging body gives a higher degree of applied force to the pedals. So, as long the speed high >40km/h, and we speak of 200-300km for a tour, you might be faster on a DF, because you actually can apply more force into the pedals, fight more air resistance - and be "faster" for a peak event. Whereas the non-DF you cannot express that peak of force on the pedals, so you ride more stress free - which means, supporting my overall impression on recumbents, a more relaxed and enduring performance.
So, this is getting more complex, and I really *love* this exchange with you Vik and others sharing the points of views.
What I expressed above is maybe the core issue - a DF is faster because you can apply a peak force, fighting more air resistance *if* you have the power, you can be fast but for the price for a lot of power you need to achieve it. The non-DF provide less air-resistance, and a limit of applicable force, not that peak force, but less.
So, Vik - you might be right saying it's a myth a non-DF is faster, because you see people able to deliver a peak performance. At the same time I'm standing true as well, as I endure longer and ride faster with my longrider than those people riding DF in tours with baggage - as those are not in the range of delivering peak performance, touring is an endurance effort solely.
So, we may conclude for a moment this, we not only need to distinct the models, DF, long, short and lowrider, but also the application, endurance, peak performance etc.
Now you asked about PBP - this is very interesting. If my raised points are weighted the way I described, the PBP and the aspect you ask about "fast & records" is then a peak performance, and not an endurance effort. This would be my rather lengthy and complex anwer to a DF if I had the time with the thoughts mentioned above.
Vik, thanks for your blog, and your endurance to keep writing and raising all those topics, it's very appreciated. Let's bounce ideas back and forth ... :-)
"How come bents don't hold any overall course records on PBP?"
Most likely because the *strongest* riders up to this point have been on uprights. To really answer this question, you'd need to get the current course record holder on a recumbent and see how it goes. Of course, there are so many other variables involved that the question would still remain veiled with doubt.
The current record holder has zero incentive to try a bent for PBP. He already has the record on a DF.
Even if we accept that the strongest rider gets the record on a DF - why haven't some of the very strong bent riders beat him given the advantages we normally attribute to bents - comfort & aerodynamic form factor. A fully faired F-40 has completed the course. It is fairly light, climbs well and is obviously very aero. Shouldn't a decent rider in a F-40 have a significant advantage over a naked DF?
BTW - anyone know what the fastest bent time is?
Shouldn't a decent rider in a F-40 have a significant advantage over a naked DF?
Nope. I think the F-40's that have been used at Paris-Brest-Paris were too heavy for a course with so much climbing.
At PBP climbing ability plays a bigger role than aerodynamics (different from RAAM, say).
I could be wrong but I think hardshell carbon fiber seats are also better for climbing.
BTW - anyone know what the fastest bent time is?
I don't know about the last PBP but in 2003 the fastest 'bent was Ben Sherratt on a Challenge Jester (65:25). For his training rides Ben rides up Mont Ventoux before the snow has melted in the spring.
The fastest 'bent in 2007 would have been Hans Wessels if he were not riding his heavy trike/velomobile/mobile grocery store. He put in a ridiculously fast time with the velomobile and rode it back and forth to Holland in record time too.
If Hans had been riding a VK2 or a Jester or something (with moderate support) he probably would have finished an hour ahead of the fastest upright rider.
I think I can summarize it further, for a better discussion:
A DF allows a higher range (speak "peak") of power applied on the pedals than a non-DF which gives some limits due the sitting position and inability to instrumentalize the body weight/gravitational force. Now, the next step is, at what velocity does the advantage of better aerodynamics kicks in for the non-DFs . . . and when you have a route with flat parts and hilly parts where you go out of this advantage and DF can keep up higher velocity peaks . . . That's it. Of course you might have a DF rider adapted delivering those peak power, whereas a trained non-DF rider adapted to distribute his power more evenly.
If we were sending four people with like conditions on PBP: DF, long, short and lowrider - we would have to measure the energy usage as well (measure weight, food intake and weight after finishing PBP) - then we could conclude also who was most efficient. The most fast would not necessarly mean also most efficient.
So - the question who is faster, DF or recumbents is rather complex, especially when you want to really explain it in details, e.g. analyze the mechanics of riding a DF (sitting, and swinging) and mechanics for long, short and lowracers.
I haven't had the chance to read Wilson's books on Cycling Science (or like title) - I would guess someone took the challenge and made an abstract on how the body does apply force on a vehicle, at what efficiency and the overall energy distribution over time involved (fitness). Anyone read Wilson's book(s) or alike books covering this aspect of human powered vehicles?
Hi Rene,
Perhaps you are on to something. I don't have the physiology background to validate it, but the max power vs. efficiency idea is interesting. When I am climbing a steep road on my DF road bike what makes me fast is the ability to shift positions to use different muscles - even get out of the saddle so that I can keep my average speed up. I can rest/recover on the downhill/flat section and be ready for another climb given a short break.
On my Fujin I can't change position or use some different muscles so I can only use my gearing wisely and train my muscles to not get tired so quickly.
Where your idea comes in is that standing on the pedals isn't very efficient, but as long as it is for a short period of time it keeps your speed high and ultimately as long as you don't burn out and you keep eating/drinking using more energy isn't a penalty in a long distance event.
Anyways it is an interesting question. I think the best we can hope for an answer is taking the observations of folks that have ridden the course {David C] and apply some logic to it.
Anyone read Wilson's book(s) or alike books covering this aspect of human powered vehicles?
Me! Me! (hand waving, jumping up and down). I've also got all the stuff he wrote in RCN and an e-mail he sent me, which immortalized my computer.
- we would have to measure the energy usage as well (measure weight, food intake and weight after finishing PBP) - then we could conclude also who was most efficient. The most fast would not necessarly mean also most efficient.
True, and the slower you go the more efficient you are, simply because of the non-linear relationship between speed and wind resistance. However you can just eat more, weigh less and plow through Paris Brest Paris like a maniac, getting it over with before chronic fatigue sets in, kind of like the Tasmanian Devil. There is also a kind of high to speeding, that helps you psychologically, even if it's not efficient.
There is no question you will be more efficient on a bike with a lower coefficient of drag but there is more to Paris Brest Paris than simple efficiency. If you go slow enough to lose sight of people who know where they are going you could get lost. That's what tends to happen to bad climbing 'bents on brevets.
Re Peak Power
You can climb hills out of the saddle, however that is definitely not efficient and professionals tend to stay in the saddle for that reason.
On brevets (on an upright bike) you HAVE to get out of the saddle on climbs to avoid butt blisters and other upright bike ailments, especially on the long rides.
On some 'bents with hardshell seats you can alter your position to climb so you can push into the seat better (with your upper back on a lowracer, for instance). On a Gold Rush with a carbon seat you can actually get off the seat and stand on the pedals like an upright cyclist (by lifting your butt and pushing off the top of the seat of the Gold Rush). That gives your butt a break and allows you to squirm around into different contortions for a bit of a refreshing break (like climbing out of the saddle on an upright bike). That position gives you the same peak power as an upright cyclist.
HOWEVER - you don't need to use that peak power on marathon events! It's not efficient. It's just a refreshing break, like getting off and stretching or stopping for ales and chickenburgers (in the middle of a brevet and then finishing 10 minutes before the cutoff).
Re Finishing Times at Paris Brest Paris
It's not a good idea to base anything on posted finishing times at PBP unless you know how that person did it. Not everybody is trying to get a low finishing time. Someone could be riding like a bat out of hell while they are riding (passing everyone) and then completely stop overnight and add 10 hours to their time.
The way anybody can get a good time at PBP is to treat it like a death march. In fact if you do not wish are dead at some time during PBP you are definitely dilly-dallying, having too much fun and probably stopping for leisurely lunches with fine wines and lengthy snoozes. To get the low finishing time you should only do one or two sleep stops of no more than two hours each. I don't know if there are any recumbent riders who are doing that.
As far as climbing on a 'bent I would think any type of hardshell seat would be more efficient at transferring all effort into the pedals. Any give at all in the seat would absorb-and therefore waste- energy.
I'm not suggesting everyone should shoot for a low PBP time. If I make it to the French Ride I'd do what Micheal Wolfe did - ride hard and sleep most of every night.
But, the fact is there are talented bent pilots who love a good death march - example the growing RAAM numbers. So you'd think somebody would be interested in setting a PBP record.
The DF Rando who asked me the question was Jan Heine of Bicycle Quarterly. His point was that if you wanted to get more randonneurs on bents get someone fast to go break the record. That would get their attention and put some pause in the typical assumptions that bents are not great rando rigs.
He also wondered aloud that the course seemed well suited to bents with no ridiculously steep climbs [like BMB] and reasonably high average speeds where the aero benefit should kick in. Not to mention the comfort advantage.
But, the fact is there are talented bent pilots who love a good death march
Speaking of which, Ken Bonner felt sorry for me and bought me a cup of coffee and we discussed marathon cycling. The ultra guys amaze me and Ken may be the most amazing of all. We discussed sleep times and Ken can (and does) go on very little sleep but he is not exactly on a death march. He is dead serious about cycling but he seems to get a great amount of entertainment value out of ultra-cycling, which may explain how he can float across the landscape with a smile on his face and a song in his heart while leaving mere mortals puking in the ditch behind him.
If I have my information correct I think it may have been Micheal Wolfe (on a Bacchetta Aero) who was the guy that temporarily got out in front of Ken (and was apparently only stopped by a midwest dust storm).
I also talked to Ken about his Cross-Canada record ride. It would be fantastic if he could do it. Cross-Canada is a lot more horrific than riding across the United States. The only thing that's stopping him is a lack of volunteers and money. I have been poking around looking for both but the potential volunteers I know are too poor to take two weeks off work and the rich people I know are all bastards.
The DF Rando who asked me the question was Jan Heine of Bicycle Quarterly. His point was that if you wanted to get more randonneurs on bents get someone fast to go break the record.
Well, that is a pretty tall order and Jan is pretty bold to say that, especially considering that he is qualified to say that, as one of the top marathon cyclists in the world and an out-in-front guy at Paris-Brest-Paris, riding in the true spirit of Paris-Brest-Paris.
It is no small feat to have the fastest time at PBP and those who have done it have been special individuals who dedicated enormous effort to preparing for PBP. I met Herman De Munck (and I went cycling with him) and he was practically a professional non-professional cyclist. Scott Dickson had a job that allowed him time to spend a tremendous amount of time on his bike (commuting to work). Susan Notarangelo was pretty well an amateur professional and had done RAAM several times.
I don't personally know of any 'bent riders with a fast enough 'bent bike that are presently in a position to go out in front at Paris-Brest-Paris. If you are out there, let us know.
PBP is a bear. It is really tough. PBP has a long and glorious history in upright cycling. Really PBP is the history of upright cycling. PBP started it all. I have done it on an upright bike myself. I am a pretty insensitive guy and PBP nearly brought me to tears. 'Bents are French culture but I think it is very ambitious to expect a 'bent out in front at these early days of 'bents in marathon cycling.
Re Boston Montreal Boston
BMB is an unusually hilly (steep hilly) ride. It's a climbers ride. For instance, I would never do it on any bike because even when I am down to .0001% body fat I still look like the left defenceman I was trained to be and I have too much upper body weight. I have ridden most of the BMB route and parts of it are simply ridiculously steep.
I'll bet solo RAAM is going to be where 'bents gain some marathon notoriety (not that I really care about such notoriety). RAAM is simply so utterly insanely crazy that crazy things will happen and I think we can count on Americans to do it because America is the land of extremes (both good and bad extremes). RAAM is the chance for Americans to prove that they are even more crazy than Europeans (and Americans love that kind of stuff).
David I think the guy you are referring to is Larry Graham on a Bacchetta Aero at the Last Chance 1200K.
http://tinyurl.com/2z6cfu
As far as not having a fast enough bent to set the PBP record what about the Fujin SLII, VK2, TiCA, Nocom etc...? Light and aero - plus they climb well.
As far as not having a fast enough bent to set the PBP record what about the Fujin SLII, VK2, TiCA, Nocom etc...? Light and aero - plus they climb well.
Light and aero yes but can they really climb (fairly steep climbs) well? All of the above have extremely laid-back seats which inhibit climbing. They all also have drive-side idlers which tend to work more efficiently with lighter riders (when climbing, especially on the least bit flexy bikes).
I think a hilly course like PBP favours a bike with a more upright seat (ie 700 x 20 configuration midracer) with a relatively lower bottom bracket.
Of the above bikes the NoCom is probably the ultimate fastest bike for a solo RAAM but brevets may be another story. That being said, normal people may prefer the more laid back comfort of a lowracer, which is a valid concern on a brevet. Long-distance comfort is probably the reason more marathon cyclists don't use Easy Racers (even though an Easy Racer may be a better climber). Being laid back is simply divine (but I prefer the bolt uprightness of an Easy Racer on Brevets). I think like Hans says, personal preference is important.
@runawayscreaming:
Tells us a bit on Wilson's books! Does he abstract the legs of the humans or the entire human body, e.g. creating a system with arms, upper body, legs as a motoric system which pushes pedals? Does he study the DF too? Sitting and swinging position. I thought last night a bit more, it's get very interesting the more one thinks about it:
The human body as vehicle to maneveur optimal on a surface of two massive (literally) different densities: earth and air. A fish operates mostly in one medium without surface - when we build a "device" to extend the operateability of the body, one has to look at the body as "device" already, why it is the way it is. Men knows at what speed change from walk to running, it's an optimum - alike a DF rider learns (my speculation) instinctevely to get out of the saddle and swing. Of course, my thoughts on the advantage of DF to instrumentalize the body weight itself as pendulum to push the pedals left and right alternating is for me the most obvious difference of 'bents vs DF.
I read few days ago an amputee was banned from the official olympics as he was running faster than any non-amputee, his protheses gave him an immense (overproportional) advancement. In that sense, a bicycle is a protheses just not that close fastened.
@vik:
Exactly, I was first also confused that I couldn't get out of the saddle of my longrider to deliver some peak speed and power - then I realized the seat and sitting position forced me in a way to stay within a range of power delivery and avoid extremes - maybe this is smart without intention by Wilson who designed that kind of longrider (I really should get more information on his ideas and motives).
It is true that standing up and swing the body (or rather swing the bicycle below) to stamp your feet on the pedals is not efficient - but I assume most racing events aren't about efficiency, it's about the ability to deliver peak power - that's also the reason I'm not really into racing sport either. Life itself forces to find optimum, you cannot deliver peak energy, you need to recover, and balance it in a long term way, because at the end your (short) life does contribute a long term idea of what humans are capable of, what I mean, we individually contribute to a collective knowledge (the internet these days a very obvious example now) how to optimize for the evolution of human. But back to the topic, as others wrote, PBP might not be really the best measure to point out 'bent advantages yet, unless we really know what PBP is in regards of power deliver requirements (how many climbings, how many forced stops like 90 deg curves, traffic lights etc where you have to slow down/stop and accelerate again).
I try to remember my time on DF, I rode it for ~18 years almost every day, at the end I had a MTB 3x7 with fenders, and I was very pleased to say at least. I had thick tired not worn out after 4-5 months but I could keep 12-18 months, and always hard tired as I had a bikestore near by with an electric driven pump.
For me the idea to use my own body energy to move myself forward, the human powered vehicle (such a precise term), interests me, simple but effective solutions. On another blog I read about that the bicycle to be the most efficient vehicle of energy to distance ("gallon per mile" called). I think it's more than a playing with numbers, but an evolutionary consideration. The idea to use up oil reserves (putting aside all political, economical stress and injustice) isn't efficient, because not renewable, not self-sustainable. As a culture it is great to use oil, energy converted in thousands/millions of years and then burned in miliseconds to provide thrust within a car engine can be looked as insane, but given the huge amount of oil gave us a way to use it wasteful speak ineffectively which slowly changes as we are forced to optimize due shortage of oil, 1500kg vehicle to transport a 75kg man. etc I'm saying nothing new here. :-)
I once dreamed of a vehicle like a motorcycle, you are laying aerodynamically forward on a two wheeler with same size wheels, you lay on the belly and chest, and the legs have free space and drive the pedals slightly behind your back - kind of a lowracer but the head in front, laying on the chest & belly, and the arms & hands pointing forward as you would swim. That would be alike running, instead touching the ground you would push the pedals as "moving/cycling ground" - I guess DF in some sense does this, except aerodynamically not the best.
Well, we are still pondering are 'bents faster truly? ;-)
As I wrote, I personally would analyze the mechanical/physiological interface closely of all bicycle types, which is a lot of work (not done in a couple of days, but rather months) and I'm missing basic physics to do this myself (or saying I'm lazy to do it myself) ;-) I would try to make a computer model, for the human body, and "apply" it on computer modeled simplified DF, long, short and longrider, simulate climbings, tire/ground friction, winds, etc tune on all natural adjustable variables and create a huge chart with dozens of graphs, and slowly some optimums would show up, giving DF advantages at certain speed ranges and power peaks, where as the non-DF would show their individuals advancement graphs.
@runawayscreaming: Do you know any work going into the direction I just brain stormed about?
@vik: This is great discussion here! Thank you for igniting it! :-D
Not "gallon per mile" but "miles per gallon" :-)
@vik:
The 24 hours record is done with a recumbent, ~1000km, so - if PBP would have no curves, no forced slowdowns or even stops but just slim climbing, a 'bent would make PBP record I'm convinced.
Btw, Wikipedia: Recumbent bicyle has become very informative too!
PS: I'm considering an extensive Europe tour this April/May/June/July, and will also ride France and "test-ride" Paris-Brest to review the terrain myself, also see if could do PBP in 90 hours ;-)
From Wikipedia: Recumbent bicycle:
Riding position
A study by Bussolari and Nadel (1989) led them to pick a recumbent riding position for the Daedalus flight even though the English Channel crossing was accomplished in the Gossamer Albatross with an upright position. Drela in 1998 confirmed "that there was no significant difference in power output between recumbent and conventional bicycling."[3]
And [3] leads to Wilson's Bicycle Science book . . .
It would be really nice to know the details of this conclusion, and I surely would know how you Vik comment this then - I think your experience with "not that faster with a 'bent" has validity, alike mine "faster with a 'bent" in the endurance application.
Tells us a bit on Wilson's books!
Well, I could not do Bicycling Science justice by reviewing it here. Suffice it to say it is partially a review of the history of Bicycling Science and it is written from the point of view of an engineer (David Wilson is an emeritus professor of engineering at MIT) so there is a scientific discipline to the book that you will not generally find in bicycle magazines. Professor Wilson is a recumbent enthusiast (but not a randonneur). I enjoy his writing and I enjoy what he has to say. There are others, such as Rich Pinto and Bram Moens who have made practical applications of bicycling science to performance bikes. Any bookstore can order Bicycling Science and it is not very expensive (maybe $30 now).
As far as biomechanical models are concerned I would say forget about even trying. There are simply too many variables. Even Finite Element Analysis of bike frames is a rather hopeless cause because of the almost infinite number of variables in every plane and direction you can think of.
The old masters of frame construction got upright racing frame design right ages ago, by art and experience. The same goes for biomechanics. The old (non-scientific) cycling coaches in Europe figured everything out a long time ago, from simple experience and intuition. All modern scientific coaching has contributed is performance enhancing drugs and masking agents.
Of course internet discussions are mostly made up of 98% nonsense from people who like making proclamations without knowledge, logic, scientific discipline or even simple reason but if you sift through the BROL discussion board you can find the 2% of info that is actually informative.
When it come right down to it the proof is in the pudding and bikes are improved through trial and error by tinkerers on a gut feeling (just like they always have been). The Wright brothers were such tinkerers and that approach obviously comes up with transportation products (some with more virtue than others - I don't know that airplanes were such a good idea but bicycles certainly were, and the Wright brothers were essentially bicycle mechanics).
As far as I know there is nobody who has managed to come up with any really useful physiological information about recumbent riding. There is some informed speculation on the BROL discussion board that seems to be sufficient for the task at hand. There are a few bikes available that are definitely going in the right direction (as far as frame design and human biomechanics are concerned) so I don't really see the point in waiting for scientific study anyway. If one is interested in performance cycling there are experienced 'bent performance cyclists available (eg John Schlitter, Freddy Markham, Vik Kumar Banerjee etc - those guys KNOW what works.
Re Belly Bikes
Sandra Sims-Martin thankfully put an end to the threat of belly bikes becoming mainstream when she finally told Gardner Martin to stop that before he smashed into something face-first (Easy Racers began as belly bikes).
There is an article on Pendal bikes in issue 28 (December 2007) of Velovision. They are kind of what you describe but look to me like a another bike design solution looking for a problem.
"If one is interested in performance cycling there are experienced 'bent performance cyclists available (eg John Schlitter, Freddy Markham, Vik Kumar Banerjee etc - those guys KNOW what works."
Hahahahaha....are you making fun of me David? Probably well deserved. I might be qualified to put air into JS' or FM's tires - perhaps pass them a power bar. But that's about it!
The one thing I have done is paid attention to successful randos like yourself, Michael Wolfe, Jan Heine, Kent P, etc... I have learned that you can't fake anything for 200K, 300K, 600K, 1200K, etc... If your theories work on a brevet they have some merit. If not it's time to throw them out and try something else.
I like what you said about the element of intuition and art in cycling. The DF folks have decades of it accomplished already which is great in that they can reap the benefits of great minds before them, but they also have less space on the map that hasn't been explored. Bents don't have the same wealth of experience to draw upon, but there is a greater sense of exploration and adventure as we boldly go where no man has gone before - feet first into the cyclo-verse!
I'd like to say I ended up on my Fujin through a comprehensive study of aerodynamic theory, cycling physiology and mechanical engineering, but truth be told I lucked out on spotting a used one on EBay, thought it looked cool and got slightly carried away with the bidding.
Some people are smart and some people are lucky I'll take what I can get.
=-)
Vik
....are you making fun of me David? Probably well deserved. I might be qualified to put air into JS' or FM's tires - perhaps pass them a power bar. But that's about it!
Uh, oh, I was posing as an anonymous yet belligerent know-it-all and you may have exposed my true identity.
As a cyclist you are taking a more rational approach to the topic than 98% of cyclists so I expect Schlitter et al to be joining you in a furious 'bent paceline at some point. You guys will be sharing stories and snickering at slower cyclists.
The one thing I have done is paid attention to successful randos like yourself, Michael Wolfe, Jan Heine, Kent P, etc...
Unfortunately I cannot be placed on the podium with the likes of Wolfe, Heine and Peterson. Those guys are men amongst men. I am a mere lumpenrandonneur and actually quite a rando-disgrace.
Since probably no one is reading this far down the page I will confess I started out training for RAAM and I went steadily downhill from there. I still have a an old RAAM poster signed by Susan Notorangelo and Lon Haldeman. I became totally demoralized and gave up on the RAAM idea when Wayne Phillips was hit by a hit and run driver in New Mexico (during the '85 RAAM).
I later had some brief moments of glory on a couple of PBP's and now I am so undisciplined I readily follow my fellow slobby randonneurs into disreputable bars for ales and ice cream mid-brevet.
...there is a greater sense of exploration and adventure as we boldly go where no man has gone before
Captain Kirk could not have put it better himself.
I have learned that you can't fake anything for 200K, 300K, 600K, 1200K, etc... If your theories work on a brevet they have some merit.
It's true. Brevets are a fantastical testing ground for what actually works. You can speak with authority once you have taken a bike on a brevet. Brevets really are races of truth.
David completing 2 PBPs and riding 300K or 600K just to get to the start of a 600K brevet gives you loads of rando credibility in my books. The last bit also makes you a bit nutty, but in a good way!
Let's continue some of this at BROL - here it's kind of cozy and small, but at BROL threading and more structured discussion is possible!
Vik, I remain a reader of your blog - so great to see people so vivid sharing their expriences, views and opinions :-)
Let's continue some of this at BROL
Actually this discussion is already underway at BROL under the heading "Data from very informal climbing test" in the General Discussion category. I'm in that discussion too, under one of my other silly made-up internet names.
Brevets are all about the climbing so the above topic is very relevant.
Lowracers and midracers obviously have the best aerodynamics (for unfaired bikes) and the ones with longer wheelbases are more comfortable. I can tell you the fastest wheel combination is 700 x 20 (especially with a rearward weight bias). The only other thing you have to know is bike weight, lateral and vertical compliance (deflection) and the rigidity of the attachment point for the drive-side idler.
The bikes with a more upright seat climb better. The bikes with a more laid-back seat are faster on the flats (but hairy-er at night).
Then there's the weirdos that ride long-wheelbase bikes. Same rules about frame deflection apply but a fairing must be used to achieve the same aerodynamic advantage as a lowracer. I not so humbly submit that a Gold Rush the same weight as a NoCom will be a much more efficient climber (due to the seat angle and direct chainline). Also, lowracers and midracers and highracers are better suited to lighter riders while climbing, not because of the mass of the cyclist but because lighter riders generally have proportionately less strength and are less likely to induce power-robbing deflection losses into the drive-side idler and mount.
Since this is not the BROL forum I can tell you that I am a huge slobbering ape of a cyclist and I can deflect the frame of certain monotube highracers so much that the chain derails. I can also tear off idler mounts while climbing and break chainstays right in half. Some of the bikes are designed for light riders (just like upright racing bikes and parts are designed for 155 lb supermodelish bike racers). Some of the general consumer 'bents are so bloody heavy because they are designed to withstand the punishment of 300 lb cyclists (and there are more 300 lb cyclists than you think).
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