4 ms·

>the contribution of the lifting leg is crucial to getting up to speed This might feel true, but it isn't. Buy or borrow a dual-sensing power meter (Garmin Ral

>the contribution of the lifting leg is crucial to getting up to speed This might feel true, but it isn't. Buy or borrow a dual-sensing power meter (Garmin Rally, SRM X-Power etc) and you can see for yourself - there's practically no useful power in the upstroke. Toe clips or clipless pedals can extend the power stroke, but only by a few degrees at the bottom of the stroke. https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-upstroke-2 https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-up... The intuition of cyclists is a very bad indicator of actual performance. For decades people thought that hard, narrow tyres were faster, but nobody had actually tested it properly. Narrow tyres have lower rolling resistance on a smooth steel drum in a test lab, but they have much higher rolling resistance on real roads with bumps and ruts. When paired with suitable rims, the reduction in rolling resistance of wider tyres more than compensates for the penalty of increased weight and drag.

ordu 3y ago
My cyclist's intuition says that leg clipping allows you to extort greater force on a down stroke. Without clipping the force is limited by your body weight, with it the only limit is your muscles. Thinking about it your hands and a back leg allow you to apply a lot of downward force to your body and your lead leg can add all this force to a stroke. It doesn't matter that your hands or back leg individually are not so strong when pulling, because their efforts are combined. In situations when you need not to extend as much force as you can, probably clips do not add much, though I do not know. I tried at some point to ride a bicycle without clips and nearly failed. My back leg tries to pull and leave a pedal. > https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-upstroke-2 https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-up... They are saying that with high rpm cyclists do not pull. I can believe that, high rpm is beneficial exactly because you need to apply a relatively small force.
stouset 3y ago
I strongly encourage you to actually test this yourself. Having personally done so myself, all I can say is that you will be surprised. Time yourself on a max-effort sprint in a high gear from a standstill. Don’t pull up on half your efforts. Pull up on half your efforts. The effect isn’t subtle. I’m not particularly convinced by power meters not showing much here. The biggest reason being that pulling up has the effect of allowing you to push even harder down. Without pulling on the handlebars or pulling up on the rear pedal, the maximum force you can exert on the pedal is a function limited by your weight. By pulling up on those three points, your ability to push down harder is significantly greater. Another simple counterexample is hills. There exist hills in my city that are physically impossible to climb without clipless pedals. You can stand on the pedal all you want, but your body weight is not enough to overcome the downward pull from the slope. On clipless pedals, while pulling up, you can climb the hill.
- hinkley 3y ago
  The summaries of these studies don’t seem to mention sprinters. Or climbers. I’m thinking the wrong people did these studies (people who didn’t actually “test it themselves”). I would also say that as a former cyclist and bike mechanic, there were thresholds of pedal adjustment where your foot would stay on the pedal if you only applied downforce, but not sufficient for any other force. It was a common enough problem that there were articles written about it. Early Look models had this problem, but not as substantially as most of their copycats. There’s a reason they had little competition for most of a decade. I think the Shimano MTB pedals (with the little countersunk cleats) sometime around 2nd Gen, were the first time Look got properly nervous. There were some people for whom you had to dial the tension to the edge of “annoying” for clipping in in order to keep them from accidentally clipping out at speed or on hills, both if which can be dangerous. Even when I had mine dialed in “right”, I ended up pulling one shoe vertically out of the pedal when I came to a stop without disengaging first. Adrenaline is a hell of a drug.
  - LargoLasskhyfv 3y ago
    Never got used to clips. Got 2 hyperbikes recently and had real trouble to get something like these https://www.indoorcycling.org/welgo-spd-kombipedale-mit-koerbchen.html https://www.indoorcycling.org/welgo-spd-kombipedale-mit-koer... , https://www.permanent-fahrrad.de/Retro-Fahrrad-Pedale-mit-Pedalhaken https://www.permanent-fahrrad.de/Retro-Fahrrad-Pedale-mit-Pe... attached to them, or get them at all. Because I'm used to them. I know them as 'Tretkorb'. How do you call them, toe clips? After about 20 years pause, only using an antique 'citybike' with three-spead gear hub and coaster brake. It feels like I can fly again! :-)
Lio 3y ago
Clipless pedals also keep your feet on the pedals at high cadences. I'd guess the highest power and torque outputs in cycling are from track sprinters. If you look at what they use it's both cleated pedals and straps. No matter how they're generating that torque they definitely don't want to slip off a pedal going full tilt. Riding a hardtail I always want clipless pedals because I don't want to have have my ankles at a weird angle just to grip pedals when I go over something rooty. > When paired with suitable rims, the reduction in rolling resistance of wider tyres more than compensates for the penalty of increased weight and drag. Unless you include specific conditions you can't really say that a hard, narrow tyre won't be faster with any confidence. At some point having even wider tyres will only slow you down because the surface bumps don't get any bigger but the cda of your front tyre and rolling resistance due to hysteresis keep increasing. e.g. a 4" fat bike tyre at 0.5bar is not going to be faster in a velodrome than a 23mm tub at 7bar just because they're wider. If you were riding on snow or cobblestones however...

ordu 3y ago

My cyclist's intuition says that leg clipping allows you to extort greater force on a down stroke. Without clipping the force is limited by your body weight, with it the only limit is your muscles. Thinking about it your hands and a back leg allow you to apply a lot of downward force to your body and your lead leg can add all this force to a stroke. It doesn't matter that your hands or back leg individually are not so strong when pulling, because their efforts are combined. In situations when you need not to extend as much force as you can, probably clips do not add much, though I do not know. I tried at some point to ride a bicycle without clips and nearly failed. My back leg tries to pull and leave a pedal. > https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-upstroke-2 https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-up... They are saying that with high rpm cyclists do not pull. I can believe that, high rpm is beneficial exactly because you need to apply a relatively small force.

stouset 3y ago

I strongly encourage you to actually test this yourself. Having personally done so myself, all I can say is that you will be surprised. Time yourself on a max-effort sprint in a high gear from a standstill. Don’t pull up on half your efforts. Pull up on half your efforts. The effect isn’t subtle. I’m not particularly convinced by power meters not showing much here. The biggest reason being that pulling up has the effect of allowing you to push even harder down. Without pulling on the handlebars or pulling up on the rear pedal, the maximum force you can exert on the pedal is a function limited by your weight. By pulling up on those three points, your ability to push down harder is significantly greater. Another simple counterexample is hills. There exist hills in my city that are physically impossible to climb without clipless pedals. You can stand on the pedal all you want, but your body weight is not enough to overcome the downward pull from the slope. On clipless pedals, while pulling up, you can climb the hill.

hinkley 3y ago
The summaries of these studies don’t seem to mention sprinters. Or climbers. I’m thinking the wrong people did these studies (people who didn’t actually “test it themselves”). I would also say that as a former cyclist and bike mechanic, there were thresholds of pedal adjustment where your foot would stay on the pedal if you only applied downforce, but not sufficient for any other force. It was a common enough problem that there were articles written about it. Early Look models had this problem, but not as substantially as most of their copycats. There’s a reason they had little competition for most of a decade. I think the Shimano MTB pedals (with the little countersunk cleats) sometime around 2nd Gen, were the first time Look got properly nervous. There were some people for whom you had to dial the tension to the edge of “annoying” for clipping in in order to keep them from accidentally clipping out at speed or on hills, both if which can be dangerous. Even when I had mine dialed in “right”, I ended up pulling one shoe vertically out of the pedal when I came to a stop without disengaging first. Adrenaline is a hell of a drug.
- LargoLasskhyfv 3y ago
  Never got used to clips. Got 2 hyperbikes recently and had real trouble to get something like these https://www.indoorcycling.org/welgo-spd-kombipedale-mit-koerbchen.html https://www.indoorcycling.org/welgo-spd-kombipedale-mit-koer... , https://www.permanent-fahrrad.de/Retro-Fahrrad-Pedale-mit-Pedalhaken https://www.permanent-fahrrad.de/Retro-Fahrrad-Pedale-mit-Pe... attached to them, or get them at all. Because I'm used to them. I know them as 'Tretkorb'. How do you call them, toe clips? After about 20 years pause, only using an antique 'citybike' with three-spead gear hub and coaster brake. It feels like I can fly again! :-)

Lio 3y ago

Clipless pedals also keep your feet on the pedals at high cadences. I'd guess the highest power and torque outputs in cycling are from track sprinters. If you look at what they use it's both cleated pedals and straps. No matter how they're generating that torque they definitely don't want to slip off a pedal going full tilt. Riding a hardtail I always want clipless pedals because I don't want to have have my ankles at a weird angle just to grip pedals when I go over something rooty. > When paired with suitable rims, the reduction in rolling resistance of wider tyres more than compensates for the penalty of increased weight and drag. Unless you include specific conditions you can't really say that a hard, narrow tyre won't be faster with any confidence. At some point having even wider tyres will only slow you down because the surface bumps don't get any bigger but the cda of your front tyre and rolling resistance due to hysteresis keep increasing. e.g. a 4" fat bike tyre at 0.5bar is not going to be faster in a velodrome than a 23mm tub at 7bar just because they're wider. If you were riding on snow or cobblestones however...