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  1. #1
    Clyde on a mission!
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    Singlespeed physics. Why SS works.

    Bear with me here, my physics knowledge is old high school stuff, going from memory.

    I just had a chat with a friend about the geared vs. ss thing and like so many other non-ss'ers he had a hard time believing me when I told him that riding ss isn't that much harder than riding geared. You've all been through the same debate a million times, no doubt..

    It got me to thinking about the physics involved.

    I weight roughly 240 lbs. My geared bike and my ss both weigh roughly the same, I'm guessing around 25 lbs. That's 265 lbs for rider and bike.

    I arrive at the foot of a particular climb. It has a particular gradient. Getting 265 lbs up that particular climb in say 1 minute takes a certain amount of kilojoules. That's just plain physics, a certain weight moved up a certain gradient in a certain time equals a certain energy required.

    It doesn't matter if I sit and spin or stand and mash, if I make it up that climb in 1 minute I've put in the same amount of energy no matter what bike I ride, if it's done sitting or standing or which gear was used. Getting to the top in 1 minute = X amount of kJ's.

    On my geared bike I have the luxury of choosing a lower gear and climbing the hill in 2 minutes rather than 1. Doing so requires me to only spend half the energy to get to the top (unless I remember my physics wrong). Same task (get 265 lbs to the top) in twice the time equals half the energy required.

    On my ss I don't have many options on how to climb the hill. Too fast in and I probably won't make it to the top. Too slow and I'll grind to a halt. I have to time it just right to get to the top.

    So what it boils down to is the difference in energy needed between climbing the hill on my geared bike vs my ss is measured in how long it takes me to get to the top. I tend to climb hills slightly faster on my ss which means it's slightly harder than climbing it on my geared bike. But it's not like it's huge difference, my estimate is that I'm probably 10% faster up a hill on my ss, which means I'm spending 10% more energy compared to riding my geared bike.

    On a complete ride I ride the climbs a bit faster on my ss but I relax more on the downhill because I can't pedal fast enough anyway and on the flat bits I go a bit slower compared to on my geared. On my geared bike I climb slower and save some energy there, but tend to ride the downhill and flats a bit faster spending a bit more energy compared to my ss.

    That explains why my overall ride time are pretty close on my ss and my geared and why riding ss isn't as impossible as the geared riders seems to think it must be.

    Then again, my physics might be rusty and my formulas off, please correct me if it's the case, but I feel it kinda explains why ss'ing isn't as impossibly hard as some believes, it's just the same weight going up the same climb but delivering the same amount of energy in a slightly different way (standing and mashing rather than sitting and spinning).

    Does it make sense?

  2. #2
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    Singlespeed physics. Why SS works.

    I like toast!

  3. #3
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    No machine, in this case a bike, is 100% efficient. While a geared bike may seem to be "easier" as in less force excreted compared to a single speed, the person does more rotation, hence increasing the distance the foot goes around. Besides this, he extra contact points in the derailleur causes energy to be wasted do to more friction. The single speed may require more force, the person will spin less decreasing total distance the foot travels around the axel. Also less energy wasted from friction. Work= Force x Distance

  4. #4
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    B+H=D^2

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  5. #5
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    ? My physics is rusty too but I remember it does not matter how long it takes, 1 minute or ten minutes moving a certain weight moved up a certain gradient is the same amount of work its just how much energy you spend a second that is different.
    2011 Kona unit with some carbon.

  6. #6
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    You're 100% correct in principle. I didn't check the numbers but it doesn't really matter because the general idea is correct: moving the weight of your body and bike upwards in a certain time requires the same amount of energy. Doing it faster means you need more watts per hour. Moving up faster could be accomplished by increasing your speed or increasing the gradient. The important figure is how high you end up vertically.

    I increased the tooth count of one of my SS rides by two in the rear to make climbing easier. After attacking the first couple of hills I was stumped because the climbs were just as hard as before. The logical explanation made me feel really stupid: of course they were as hard, because I was riding just as fast as before, just spinning at a higher cadence. It's pretty clear when you think about it in terms of physics.

    What does affect the equation is that there is an optimum cadence for your power output, and the closer you are to (your) optimum, the more efficient you are. Too fast or too slow means you're wasting energy, even though the work you do is the same.

    So if you happen to climb a certain hill at a speed that puts you in optimum cadence on your SS machine, riding a geared bike up the same hill at the same speed would be harder.

  7. #7
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    Quote Originally Posted by ALBM View Post
    I like toast!
    Biscuits are better.
    Just stick it in granny and start grinding.

  8. #8
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    Work and energy are measured in joules. Watts on the other hand is the amount of work/time. And I agree biscuits are way better then toast. Maybe a little honey drizzled ovEr them.

  9. #9
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    Blah, to much mathematical nonsense. I just ride to have fun. Let geared riders think they have it easier if it lets them sleep better at night. We all know SS is more fun and that's all that really matters anyway!
    SS ==> Nut up or Shut up!

  10. #10
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    Climbing the same climb with constant gradient and with no obstacles at any speed (constant) requires the same mechanical work/energy (joules/kalories). But if you climb 2 times faster your power=work/time (watts) would be 2 times greater. But when the gradient is not constant and there are some obstackles, the faster you go the easier it is because of the momentum. If you are spinning a granny gear there is no momentum to help you. Another reason may be personal preferences and has to do smth with psychology - it seems easier for me to attack the climb at max effort and to get to the top fast (what you do on SS) than spin, spin and spin to the top for a long time.

  11. #11
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    I ride a SS because it's fun and people think I'm some kind of a maniac w/ unlimited power. I don't buy the, "I ride a SS so i don't have to think about shifting gears". Please... if you have to think about shifting gears, and its a strain.... , you have other issues. I rarely ride my 1X9 and don't have issues about thinking about shifting. Most of us ride SS's because: it's quiet, harder and people think we are brutes, crazy, and no bleeping miss shifts.
    As for the physics, Potential energy equation doesn't change. PE = m x g x h
    So, Slow with east revolutions or faster with harder revolution requires the same energy. It's the same energy needed to get to the top. If you are a masher, go with a SS. If you are a spinner go with a geared and spin away. I prefer to get there faster, and use a big gear , this way my downhill bombing gets more pedaling than most SS. Nice post. Making the SS's think.

  12. #12
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    Climbing a hill with 32/20 gearing- Heart rate: 220. vision: blurry. brain function: minimal- basic life support functions only.

    Climbing same hill with 32/28 gear- Heart rate: chill. vision: "pretty flowers!" brain function: "I'm bored".

    I agree with the premise that momentum is your friend and that many times a quick burst of power is more economical than down shifting. Usually you have to pay for speed though and that cost is often measured in oxygen deprivation and pain, and there aint no formula that's gonna convince me otherwise.

  13. #13
    Clyde on a mission!
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    Quote Originally Posted by J.B. Weld View Post
    Climbing a hill with 32/20 gearing- Heart rate: 220. vision: blurry. brain function: minimal- basic life support functions only.

    Climbing same hill with 32/28 gear- Heart rate: chill. vision: "pretty flowers!" brain function: "I'm bored".
    That is correct assuming that you climb the hill slower with the 32/28 gear.

    If you ride the 32/28 to the top in the same time you do on the 32/20 then you're going to get just as blurry visioned, you're delivering the same amount of joules over the same amount of time, you're just spinning your legs faster to do it.

    Saul has a point though, at some rpm your body is better at delivering power, which again can mean that climbing with a 32/28 gear is better suited for your "optimum rpm" than the 32/20 gear, so even though the energy needed is the same, you'll have an easier time delivering it because the cadence suits you better.

    So try hammering up a particular hill in a tall gear while running a stopwatch, then try repeating the climb in a lower gear while aiming to set the same time as before. Same hill, same time to the top = same amount of energy needed - being geared just allows your to choose at what rpm to deliver that energy.

  14. #14
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    Screw physics - it just forces you to HTFU!

  15. #15
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    Quote Originally Posted by kjlued View Post
    Biscuits are better.
    No biscuits or toast.

    Crushing roadies on climbs with a 25 lb. large volume tire buzzing SS 29er is far more satisfying than either breakfast food

  16. #16
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    I won't try and get into much of a physics discussion- I'm a bike mechanic who's education is all focused on human performance, anatomy, and physiology, with not a lot of mathematics or high-level physics.
    What I do experience, however, is that after 12 years of riding exclusively SS off road I have a harder time climbing with gears.
    I'm expected, when the bike shop I work for has an employee demo day, to demo bikes we sell. I'll invariably have much more difficulty climbing stuff on a geared bike that I normally climb on the SS.
    Adaptation's an amazing thing.

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  17. #17
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    Quote Originally Posted by Sandrenseren View Post
    So try hammering up a particular hill in a tall gear while running a stopwatch, then try repeating the climb in a lower gear while aiming to set the same time as before. Same hill, same time to the top = same amount of energy needed - being geared just allows your to choose at what rpm to deliver that energy.
    Theoretically if I climbed the same hill at the same speed in different gear ratios the energy used might be equal but in reality this test isn't possible because if I hammer up a hill in a 32/20 there is no way I could equal that time using a 32/28.

    You can run a car up a hill in a lot of different gears but there is always one that is the sweetest, and there will come a time when the grade becomes too steep for the motor to pull in 5th gear and you'll have no choice but to downshift, stop, or bust a rod.

  18. #18
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    Quote Originally Posted by Saul Lumikko View Post
    You're 100% correct in principle... It's pretty clear when you think about it in terms of physics. What does affect the equation is that there is an optimum cadence for your power output, and the closer you are to (your) optimum, the more efficient you are...
    This ^ exactly explains how each SS rider discovers their own magic gear.

    Never been a spinner, I tend to grind away in a bigger gear than most.
    Once going SS, find I change gear combos to fit the trail, and maximize flow.
    Know that I can stand / mash my way up a hill following a geared rider spinning away, and if I pass, am able to say Hi & thanks, while often they're sucking wind. Not implying that I'm fast, or in shape, only that I'm operating within my comfort zone, which is at a very low cadence. When riding gears, sustained climbing above 90 rpm makes me implode.

  19. #19
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    Quote Originally Posted by Sandrenseren View Post
    .

    I weight roughly 240 lbs. My geared bike and my ss both weigh roughly the same, I'm guessing around 25 lbs. That's 265 lbs for rider and bike.

    I arrive at the foot of a particular climb. It has a particular gradient. Getting 265 lbs up that particular climb in say 1 minute takes a certain amount of kilojoules. That's just plain physics, a certain weight moved up a certain gradient in a certain time equals a certain energy required.
    You're not taking into account Newton's Second Law of Motion- which has an effect on VO2 Max and strength fatigue.

    Here is an example:

    Grab a 35 pound dumbbell. Do the max number of curls. Let's say you do 10.

    Now fully rest back to 100%. Grab a 70 pound dumbbell and do do curls. With your logic you should be able to do 5 reps. After all, it uses the same amount of energy to move twice as much weight half as many times. But that is not true. It is doubtful that you would be able to do even 1 rep of 70 pounds if your max rep curl with half the weight is 10.

    Here is another example:

    Jump on a treadmill. Set it to 6mph. Run 2 miles. Now fully rest, set the speed to 12mph, and run for 1 mile. Piece of cake right? It's twice as fast but only half the distance. You could be able to do that just as easily as you did the 2 miles at 6mph right?

    Newton's second law says Force = Mass times Acceleration. In my example of the dumbbell It takes more Force because the Mass is twice what it was. In my example of running the Acceleration is doubled so it is going to require more Force (energy).

    Having gears lets you go slower (less Acceleration). Which ends up as less Force so your VO2 max, oxygen, muscles, etc... won't be taxed as much. This means you can exert yourself at a comfortable level for much longer than someone going 100% out on a SS- even if the SS rider is going much faster (assuming fitness levels are equal). The SS rider has to have the Acceleration to move his/her mass up the hill. This uses more Force and causes quicker Oxygen debt and muscle fatigue.

    SS riding works because it raises the training standard and makes our bodies extremely fit through interval like exertion (which has been proven in countless studies to be more effective than a constant low aerobic method of training). We have no choice but to push up hills as fast as possible or we won't make it up. That type of training environment isn't available to a geared rider because there is always the temptation of downshifting to reduce Acceleration and make the ride easier on the oxygen debt. Take that fit SS rider, throw him/her on a geared bike, and they would still outperform the average fit geared rider because of VO2 max and strength levels gained through interval training.

    The reason your SS times and geared bike times are around the same is all mental. If you're good with all your shifting, and monitored your hear rate/ oxygen levels during the ride, and set your gears to put the most efficient amount of exertion on your climbs- than the geared bike should be faster. Don't be worried though- cause I'd bet that most of the riders on this forum are faster on a SS than on the same bike with gears. SS is a simple way to raise the training levels of your ride. The bike forces you to HTFU in a way that keeps us pushing our fitness levels.

  20. #20
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    my feeling is that depending on your level of fitness, gearing and trails, there is a "sweet spot" with SSing where once conditioned, you get all the benefits of constant momentum, carrying off tech obstacles faster, cornering and climbing faster, drivetrain efficiency, and less wheel slippage with speed and gearing. I am not so sure that this would apply to all trails for all riders...the best riders will still be the ones that perform really well on all terrain. For a lot of singletrack without huge sustained climbs SSing works really well.

  21. #21
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    Quote Originally Posted by michaelscott View Post
    You're not taking into account Newton's Second Law of Motion- which has an effect on VO2 Max and strength fatigue.

    Here is an example:

    Grab a 35 pound dumbbell. Do the max number of curls. Let's say you do 10.

    Now fully rest back to 100%. Grab a 70 pound dumbbell and do do curls. With your logic you should be able to do 5 reps. After all, it uses the same amount of energy to move twice as much weight half as many times. But that is not true. It is doubtful that you would be able to do even 1 rep of 70 pounds if your max rep curl with half the weight is 10.

    Here is another example:

    Jump on a treadmill. Set it to 6mph. Run 2 miles. Now fully rest, set the speed to 12mph, and run for 1 mile. Piece of cake right? It's twice as fast but only half the distance. You could be able to do that just as easily as you did the 2 miles at 6mph right?

    Newton's second law says Force = Mass times Acceleration. In my example of the dumbbell It takes more Force because the Mass is twice what it was. In my example of running the Acceleration is doubled so it is going to require more Force (energy).

    Having gears lets you go slower (less Acceleration). Which ends up as less Force so your VO2 max, oxygen, muscles, etc... won't be taxed as much. This means you can exert yourself at a comfortable level for much longer than someone going 100% out on a SS- even if the SS rider is going much faster (assuming fitness levels are equal). The SS rider has to have the Acceleration to move his/her mass up the hill. This uses more Force and causes quicker Oxygen debt and muscle fatigue.

    SS riding works because it raises the training standard and makes our bodies extremely fit through interval like exertion (which has been proven in countless studies to be more effective than a constant low aerobic method of training). We have no choice but to push up hills as fast as possible or we won't make it up. That type of training environment isn't available to a geared rider because there is always the temptation of downshifting to reduce Acceleration and make the ride easier on the oxygen debt. Take that fit SS rider, throw him/her on a geared bike, and they would still outperform the average fit geared rider because of VO2 max and strength levels gained through interval training.

    The reason your SS times and geared bike times are around the same is all mental. If you're good with all your shifting, and monitored your hear rate/ oxygen levels during the ride, and set your gears to put the most efficient amount of exertion on your climbs- than the geared bike should be faster. Don't be worried though- cause I'd bet that most of the riders on this forum are faster on a SS than on the same bike with gears. SS is a simple way to raise the training levels of your ride. The bike forces you to HTFU in a way that keeps us pushing our fitness levels.

    Excellent points and well said, I highlighted my 2 favorites.

  22. #22
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    SSing allows me to drink more beer.

  23. #23
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    Quote Originally Posted by J.B. Weld View Post
    Theoretically if I climbed the same hill at the same speed in different gear ratios the energy used might be equal but in reality this test isn't possible because if I hammer up a hill in a 32/20 there is no way I could equal that time using a 32/28.
    Then reverse the experiment, try getting up a hill as fast as possible using 32/28, then try to match the time on the 32/20. Apart from your body's "comfort zone cadence" it isn't really the gear that determines how hard a climb is, it's the speed.

    Quote Originally Posted by J.B. Weld View Post
    You can run a car up a hill in a lot of different gears but there is always one that is the sweetest, and there will come a time when the grade becomes too steep for the motor to pull in 5th gear and you'll have no choice but to downshift, stop, or bust a rod.
    Yes, but engines have a defined and constant power curve. If your car can deliver 78 hp at 3500 rpm, it can deliver 78 hp at 3500 rpm all day.

    The human body doesn't work the same way. If I can deliver 200 W spinning at 85 rpm I can't keep it up for long before my body overheats and my legs burn.

    There is a particular very, very steep hill on my usual route. I've climbed it at a snails pace in granny gear and I've climbed it quite a bit faster in a taller gear. Doing it faster means spending quite a bit more energy, so slow and granny should be the way to go. However at slow and granny my heart rate keeps climbing and I have a hard time getting to the top before everything gets blurry. In the taller gear I'm faster, my heart rate goes up faster, but I manage to get to the top before I explode.

    So even if climbing that hill faster means spending more energy, my body has an easier timer delivering that higher energy for a shorter time rather than delivering a lower energy for a longer time.

    Quote Originally Posted by michaelscott View Post
    Grab a 35 pound dumbbell. Do the max number of curls. Let's say you do 10.

    Now fully rest back to 100%. Grab a 70 pound dumbbell and do do curls. With your logic you should be able to do 5 reps. After all, it uses the same amount of energy to move twice as much weight half as many times. But that is not true. It is doubtful that you would be able to do even 1 rep of 70 pounds if your max rep curl with half the weight is 10.
    If I gained another 240 lbs I wouldn't be able to climb anything.

    Quote Originally Posted by michaelscott View Post
    Jump on a treadmill. Set it to 6mph. Run 2 miles. Now fully rest, set the speed to 12mph, and run for 1 mile. Piece of cake right? It's twice as fast but only half the distance. You could be able to do that just as easily as you did the 2 miles at 6mph right?
    Both your examples fail because they both put me out of what my body is capable off.

    I would probably be able to do 20 reps or more with a 17 pound dumbbell or walk 4 miles or more at 3 mph, which makes the same point, only in a direction that's physically possible for me.

    Quote Originally Posted by michaelscott View Post
    Having gears lets you go slower (less Acceleration). Which ends up as less Force so your VO2 max, oxygen, muscles, etc... won't be taxed as much. This means you can exert yourself at a comfortable level for much longer than someone going 100% out on a SS- even if the SS rider is going much faster (assuming fitness levels are equal). The SS rider has to have the Acceleration to move his/her mass up the hill. This uses more Force and causes quicker Oxygen debt and muscle fatigue.
    Agreed. Going slower uses less energy.

    Quote Originally Posted by michaelscott View Post
    SS riding works because it raises the training standard and makes our bodies extremely fit through interval like exertion (which has been proven in countless studies to be more effective than a constant low aerobic method of training).
    How does that explain that my first ride on my SS worked pretty well too? Did my body suddenly become much fitter because I left the gears at home?

    I agree that ss is a great work out and over time it makes you a stronger rider, no doubt in my mind about that.

    But ss also works for first timers, not because they suddenly become stronger, but because as long as they ride at roughly the same pace as they are used to, they use the same amount of energy. Surely they get better at climbing after a handful of rides, not because they have become much stronger, but rather because they get more and more used to delivering power by standing and mashing.

    Like sslos says, he's having a hard time riding with gears. Not because bringing gears suddenly makes him weaker, but because sitting and spinning is no longer the way his muscles is trained to deliver the energy needed to get to the top.

    I don't buy into this "ss makes you superman" stuff. I ride ss but am no superman. I don't have to be superman because there isn't much difference between the energy I need to deliver riding ss rather than geared, I just have to deliver it using my "standing and mashing muscles" rather than my "sitting and spinning muscles". The overall energy needed is roughly the same because the hills are the same, I weight the same and the speed is roughly the same.

  24. #24
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    How tall are you?

  25. #25
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    SS doesn't work any better than geared. It just forces you to ride better and more efficient, to use momentum, to brake less.

    Though rigid really works better and is much more efficient on climbs than suspension (at least on not very tachnical climbs).

  26. #26
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    Quote Originally Posted by Sandrenseren View Post
    Then reverse the experiment, try getting up a hill as fast as possible using 32/28, then try to match the time on the 32/20. Apart from your body's "comfort zone cadence" it isn't really the gear that determines how hard a climb is, it's the speed.

    For most people their "comfort zone cadence" is pretty much the same zone they can effectively apply power, somewhere about 50-100 rpm. There are several climbs I encounter where a 32/28 is about the tallest gear I can handle and still stay reasonably fresh. I'm not talking about sitting and spinning, I mean steep sections with technical elements that (for me) require standing. I can, and have done the same climb on my SS 32/20 gear lots of times but in order not to drop below the minimum cadence required to remain upright I have no choice but to temporarily exceed my capabilities (oxygen debt) and increase speed. If the climb is short enough I'll make it in a smoking time and maybe not even pass out while sucking wind and coasting as I recover.

    "it isn't really the gear that determines how hard a climb is, it's the speed."

    I'll agree with half of that. Speed does usually determines how hard a climb is, but the gear can absolutely determine (or limit) your speed, as mentioned in my example above. So unless you really are Superman or there are no steep climbs in your area, or your SS is geared really low then there are going to be times when you'll have to either bust a nut or get off and push.

    I think michaelscott really nailed it when he said that Single Speeding makes our bodies extremely fit by forcing interval like exertion. I never thought of it like that before but I reminds me of my old roadie days and that is exactly how we would do interval training- steep hill, over geared, go as hard as you can and try not to black out, repeat.

    Time and again I hear that gears = sitting and spinning and SS = standing and mashing and I believe that's the crux of the misunderstanding. There are all sorts of riders and many different circumstances but speaking for myself as a long time geared rider and a relative "newbie" on a single speed I have very rarely used gears to sit and spin on climbs and have always found it more effective to lower my rpm's and stand a lot even on road rides, and doubly so off road. I think SS bikes are faster for a lot of people because they don't use gears effectively. I don't mean this as an insult to anyone, I get SS and think is worthy enough to stand on its own without needing to justify it in any way.

  27. #27
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    I agree to that last paragraph 100%. Riding a SS will can really improve how you use your gears.

  28. #28
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    Quote Originally Posted by Saul Lumikko View Post
    You're 100% correct in principle. ...


    What does affect the equation is that there is an optimum cadence for your power output, and the closer you are to (your) optimum, the more efficient you are. ...
    So if you happen to climb a certain hill at a speed that puts you in optimum cadence on your SS machine, riding a geared bike up the same hill at the same speed would be harder.
    How fast you climb any grade is power limited. Meaning that to take 200lbs from 1000ft to 2000 feet in 10 minutes takes the same power. What is the limitation is not the power, but the power out put of the rider and more importantly what cadence that power out put occurs and for how long.

    Like a car engine there is a peak RPM at which power occurs. Spin the motor too slow and you have no power, spin to fast and you lose power. So max speed occurs when you are at max power. Pretty obvious. For riders however there are two max power points. One is burst power where you can exert alot of power for a short duration. The other sustained power. No only are the numbers different, but they tend to occur at different RPM. Most riders can exert big power by standing and mashing hard, but they can't do it for very long. If they sit and spin they can achieve high power and sustain that power.

    Where SS comes in is that your RPM is limited by your ground speed. Such that depending on terrain you tend not to be at your ideal cadence for most of the ride. Now if you have selected gearing properly you will be closer to your idea cadence for a good chunk of the ride. The more variations in steepness up and down the more geared bikes have an edge because you can change gears to optimize the RPM and cadence.

    To be a good single speed rider you need to be able to both mash at low rpm cadence with good power for long distances and be able to spin at a high cadence. The drive train is more efficient at each pedal stroke and the bike will be lighter without all the geared bits, but faster or slower depend on terrain and rider.
    Joe
    '12 Santa Cruz Highball 29", '13 Santa Cruz Solo 27.5", '06 Rocky Mtn Switch 26" XC, AM, blah blah blah.. I just ride.

  29. #29
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    You're essentially right but you've got your definitions a little screwed up. By climbing a hill faster you're producing more POWER (work/time), measured in Watts, but you're not doing any more work (work equals weight x distance moved against gravity). Climbig the hill in a given time yields equal work and power output regardless of gear ratio. The difference in effort is due to the gear multiplier and difference in mechanical advantage you get with different ratios.

    I ride ss and I think a big reason why you can ride them so fast is because the rider will tend to make adjustments for terrain, such as climbing out of the sadle, taking advantage of body weight, rather than just sitting and spinning as you tend to do on a geared bike. There is a small efficiency advantage to a ss, related to optimized chainline, and lastly, ss riders are probably fitter than the average rider of a geared bike.
    Last edited by Blue Sugar; 04-02-2013 at 11:00 AM.
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  30. #30
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    Sandrenseren, the reason why your first time with a SS bike worked so well was most likely mental. They aren't magic machines, just bikes with one gear instead of several and a little bit less friction losses. Everything else is about the rider, both physically and mentally.

  31. #31
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    Wow, there's a lot of words and theories in this thread. I didn't read it though, except the parts about toast and biscuits. I like toast and I like biscuits. But, I usually enjoy strawberry jam on biscuits, but now I'm going to need to try drizzling some honey on them too.

    Oh yeah, and I like single speeds too. Because riding my single speed makes me happy. Except when I don't feel like riding my single speed and ride a geared bike instead. And I've found that the best course of action, when enjoying a single speed, is to not care too much what other people are riding or prefer to ride or think about your ride.

    What were we talking about again?

  32. #32
    The need for singlespeed
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    After reading this thread, I'm thinking maybe we should apply "no child left behind" to high school physics classes.

  33. #33
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    It so often on a thread like this, t seems like everyone is talking about one kind of trail with one kind of climb. My ss is awesome on flowey trails with short to moderate (1-5 minute) climbs. On techy trails with long climbs, a 2 hour ride on my ss seems equal to a 3 hour ride on my geared bike. YMMV

  34. #34
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    Quote Originally Posted by Saul Lumikko View Post
    Sandrenseren, the reason why your first time with a SS bike worked so well was most likely mental. They aren't magic machines, just bikes with one gear instead of several and a little bit less friction losses. Everything else is about the rider, both physically and mentally.
    This is why I made the thread in some way.

    I agree that an ss bike isn't a magic machine, it doesn't give wings and suddenly make me stronger. I believe it makes me stronger in the long run, gives a more complete work out so to speak, but for that first ride I was still the same rider with the same abilities as the day before on my geared bike.

    Mentally I was certain that riding ss would be A LOT harder than riding geared, but it turned out that my body disagreed and coped pretty fine just the same.

    So on the first ride, I wasn't suddenly stronger, the bike didn't do the extra work for me and even though I didn't believe I would be able to do it, my body surprised me and made it work anyway. The conclusion has to be, that riding ss isn't all that much harder than riding geared. A little bit harder because you can't always be in your comfort zone, but apart from that it's pretty much the same. If it wasn't close to the same, I would have bonked big time on that first ride.

    That experience led me to look for an explanation on why it didn't bonk me, and I believe that the explanation is to be found in the physics illustrated in this thread.

    According to physics, riding ss should only be slightly harder than riding geared.
    According to my experience first time riding ss, it was only slightly harder than riding geared.

    I believe riding ss makes you stronger in the long run. I also believes it makes you stronger mentally, discovering what you need and don't need to get by. But I don't believe that it the reason ss works, because I started out a disbeliever with "geared" strength.

  35. #35
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    And it's an important thread in my opinion. Sharing ideas and experience brings up fresh viewpoints.

    The fact that you were prepared for a much harder ride could have made it feel easier. Our mind can sometimes work in ways that surprise us. On the flipside a rider who thinks they have a high performance bike is able to put more effort into riding, which would imply the opposite. My first time riding a trail on a singlespeed bike was quite similar: not at all as hard as I thought it would be.

    A similar eye-opening experience was the one I told about earlier: I made the gear ratio easier by two teeth in the rear, but hills felt just as hard, because I was attacking them as fast as before. The difference in gear ratio didn't change my cadence enough to make a big difference in efficiency.

    In a nutshell I'd say that climbing a hill on a bike is as hard as you make it. As long as you're in a decent cadence range on your SS bike, it isn't any harder than on a geared bike. If you happen to be in your optimum cadence, it's easier with SS. The cadence has to drop really quite low before it gets harder compared to a geared bike. If the climb is an easy one it isn't harder on SS - you're just a bit slower.

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    "According to my experience first time riding ss, it was only slightly harder than riding geared."

    You must have some flat-ass trails my friend.

  37. #37
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    FACT: The more varied the terrain the less efficient a single speed will be and the more you appreciate gears.
    My rides:
    Lynskey Ti Pro29 SL singlespeed
    KHS Team 29
    S-Works Roubaix SL3 Dura Ace
    KHS CX 550 cyclocross

  38. #38
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    Quote Originally Posted by serious View Post
    FACT: The more varied the terrain the less efficient a single speed will be and the more you appreciate gears.
    fact
    /fakt/
    Noun

    A thing that is indisputably the case.
    Information used as evidence or as part of a report or news article.

    Synonyms
    reality - deed - actuality - truth - case - circumstance

    I disagree. Flats are where I appreciate gears the most. I ride lots of varied terrain on a single speed and enjoy it. I think the word you are searching for is OPINION

  39. #39
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    Quote Originally Posted by grundy View Post
    I disagree. Flats are where I appreciate gears the most. I ride lots of varied terrain on a single speed and enjoy it. I think the word you are searching for is OPINION
    No it is a fact, but if you are clueless then it becomes opinion. Your statement that you appreciate gears on flats supports my "opinion"! What is less varied than flat terrain?

    And I am talking about racing and performance, not just "enjoying riding a single speed", so when you see single speeders winning World Cup races, you get to be right.
    My rides:
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    S-Works Roubaix SL3 Dura Ace
    KHS CX 550 cyclocross

  40. #40
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    Quote Originally Posted by serious View Post
    No it is a fact, but if you are clueless then it becomes opinion. Your statement that you appreciate gears on flats supports my "opinion"! What is less varied than flat terrain?

    And I am talking about racing and performance, not just "enjoying riding a single speed", so when you see single speeders winning World Cup races, you get to be right.
    Huh?
    Oh well, I don't want to derail the OP's thread. Let's all enjoy our single speeds!

  41. #41
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    Hopefully not redundant but cant help myself

    Work has nothing to do with time amount of force over a distance

    Power is work over time, an instantaneous reading or an average reading over a set time

    From a Bike (SS or geared) perspective, do route A you do the same amount of work (not including weather etc.), if we do route A faster than another time you did route A you put more Power out that day

    Hope that helps. For Me SS is about making a usual Trail Different or more challenging just to change it up a little for the pure enjoyment of it. Fact my SS is also Rigid and now WW helps me improve as a trail rider.
    XC, Road, XXC, Endurance, Mtn, All-Mtn, Cross, Gravel, just go have fun on 2 wheels!

  42. #42
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    Work?, not interested, I like to think in terms of play.

  43. #43
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    Serious is half right. The least varied terrain is a velodrome and those things don't have gears. So varied terrain is where gears offer a benefit in efficiency. However, it's up to personal preference whether we appreciate it or not. Appreciation of the bike and enjoying the ride doesn't depend on things you can calculate with facts and hard science.

    Grundy, the reason why you appreciate gears on flat parts is because the single gear ratio is chosen to handle climbs and such as well, so a SS MTB on flats means you have to spin the cranks like mad and still won't go very fast. I also ride SS and fixed bikes on the road, it's just a matter of choosing the right gear ratio. I certainly don't miss gears on flats when flats and mild hills are all I ride. In really varied terrain I could benefit from gears, because very steep climbs would be easier and I could pedal more speed when going downhill and on flats.

  44. #44
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    Quote Originally Posted by Saul Lumikko View Post
    Serious is half right. The least varied terrain is a velodrome and those things don't have gears.
    Due to regulations they are not allowed to have gears. They are all singlespeed fixies. You can't really conclude anything from that, it's just how the rules are.

    Quote Originally Posted by Saul Lumikko View Post
    So varied terrain is where gears offer a benefit in efficiency.
    Gears offer a benefit on any terrain, it's just that it's a lot smaller benefit than most people make it out to be.

    Lets not get derailed here, riding ss is harder than riding geared in almost every situation. Once in a while you hit your comfort zone perfectly on the ss and have a slight advantage over the geared bike with rear derailleur cogs creating a tiny bit of drag, but in general those situations are few and far apart. In the vast majority of time riding ss puts you at a slight disadvantage compared to riding geared.

    The important bit being, and the point I tried to illustrate with this thread, is that even though riding ss is harder than riding geared, it's only slightly harder because you're still hauling the same weight up the same hills, only at a slightly different speed and/or at a slightly less optimum cadence.

    Quote Originally Posted by Saul Lumikko View Post
    However, it's up to personal preference whether we appreciate it or not. Appreciation of the bike and enjoying the ride doesn't depend on things you can calculate with facts and hard science.
    Absolutely agree.

    I'm not trying to drown out the enjoyment of riding ss in any way, I'm just speculating on why riding ss isn't as stupidly hard, bordering on the impossible, as some geared riders seems to believe. It surprised me that switching to ss wasn't that much harder, this thread is just about trying to figure out why it isn't.

  45. #45
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    Quote Originally Posted by Saul Lumikko View Post
    Serious is half right. The least varied terrain is a velodrome and those things don't have gears. So varied terrain is where gears offer a benefit in efficiency. However, it's up to personal preference whether we appreciate it or not. Appreciation of the bike and enjoying the ride doesn't depend on things you can calculate with facts and hard science.

    Grundy, the reason why you appreciate gears on flat parts is because the single gear ratio is chosen to handle climbs and such as well, so a SS MTB on flats means you have to spin the cranks like mad and still won't go very fast. I also ride SS and fixed bikes on the road, it's just a matter of choosing the right gear ratio. I certainly don't miss gears on flats when flats and mild hills are all I ride. In really varied terrain I could benefit from gears, because very steep climbs would be easier and I could pedal more speed when going downhill and on flats.
    Yes personal preference rules when it comes to what we appreciate. Nobody can deny that.
    My rides:
    Lynskey Ti Pro29 SL singlespeed
    KHS Team 29
    S-Works Roubaix SL3 Dura Ace
    KHS CX 550 cyclocross

  46. #46
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    Ill join. Just went rigid and abusing the hell out of and. LOVE IT.



  47. #47
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    Quote Originally Posted by Sandrenseren View Post
    I'm just speculating on why riding ss isn't as stupidly hard, bordering on the impossible, as some geared riders seems to believe. It surprised me that switching to ss wasn't that much harder, this thread is just about trying to figure out why it isn't.
    The human body does more than we think it can. As geared riders, we're led to believe that constantly changing the chain's mechanical advantage over the hub is not only good, it's required.

    As SS'ers, we learn that the body can change its output very quickly, and instead of using mechanisms to increase mechanical advantage, we just focus on conserving momentum and changing power output instantaneously to meet the needs of the terrain.

    There's a hill on a road course I like that is just plain steep and nasty. First time I rode it on my SS fixie road bike with 44/17 gearing, I realized how strong I have always been and how the illusion of always feeling compelled to change gears for efficiency is just that.

  48. #48
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    Quote Originally Posted by Sandrenseren View Post
    Like sslos says, he's having a hard time riding with gears. Not because bringing gears suddenly makes him weaker, but because sitting and spinning is no longer the way his muscles is trained to deliver the energy needed to get to the top.
    I recently experienced this same thing, trying 1x9 after riding exclusively on SS. I definitely had a tougher time on gears. It took me 5 tries to clear one certain climb while on granny, with the last try barely just making it. Same climb, it took me one try on SS without even trying. Sitting and spinning definitely works your muscles out differently than standing and mashing and affects control. This started to make me wonder about two things...1) maybe it's the geared riders who should be thought of as being more "impressive" and 2) maybe SS-exclusive riders would benefit from riding gears once in a while, as their muscles would be worked out in other ways. In other words, SS riders may ride stronger, longer and faster if there was more sitting and spinning on the same climbs that we'd normal stand and mash.

  49. #49
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    That is a SWEET bike!! Well done. I am thinking of selling my 2010 Stumpy Comp29er and getting the Carve. I've ridden my friends SS a few times and enjoyed the hell out of it.

  50. #50
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    It's a good thing that you all get up hills using leg power instead of physics calculations.

    Have you guys really been wearing your helmets?
    "Head injuries are pretty high-consequence" - AndrwSwitch

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