Bike knowledge
June 16, 2012 2:24 PM Subscribe
Three bicycling questions put forth by a 52 year old entering his second year of triathlon training. Concerning: hill climbing optimal gears; efficiency on rides; will a better bike make it faster/easier....
Me: 52 years old, male, bit on the heavy side. Completed two sprint triathlons so far.
My bicycling questions:
1. Climbing a hill, for sake of question, let's say gear combination front-2--->rear-2, 'feels' about the same as front-1(smallest)--->rear-4. is there a benefit energywise to using the small hill climbing gear up front... Like more torque= less energy required to crank? Or is the energy required all the same?
2. A few days ago I did a 10 mile ride that wiped me out. Today I did a 12 mile ride, over similar terrain, and I rode faster on average and was less tired when I finished. Are there efficiency practices for biking so one does not waste energy like I did on the first ride? Ie how do you ride most efficiently?
3. I'm getting ready to upgrade from a somewhat light "urban" type bike (specialized) to something sleeker and lighter- road bike. Can I expect this to make a difference to a fairly slow rider like me? Or will I just think I'm faster?
Me: 52 years old, male, bit on the heavy side. Completed two sprint triathlons so far.
My bicycling questions:
1. Climbing a hill, for sake of question, let's say gear combination front-2--->rear-2, 'feels' about the same as front-1(smallest)--->rear-4. is there a benefit energywise to using the small hill climbing gear up front... Like more torque= less energy required to crank? Or is the energy required all the same?
2. A few days ago I did a 10 mile ride that wiped me out. Today I did a 12 mile ride, over similar terrain, and I rode faster on average and was less tired when I finished. Are there efficiency practices for biking so one does not waste energy like I did on the first ride? Ie how do you ride most efficiently?
3. I'm getting ready to upgrade from a somewhat light "urban" type bike (specialized) to something sleeker and lighter- road bike. Can I expect this to make a difference to a fairly slow rider like me? Or will I just think I'm faster?
You should spin. A lot. Meaning high RPM with easy gear and pay attention to pedal position and pulling up with the feet (are you using clips or clip less pedals?) legs should stay over the pedals. I'd avoid honking (side to side low-RPM climbing) unless you're going up L'Alpe d'Huez.
Effective Cycling by Forester is your bible.
posted by Ironmouth at 3:23 PM on June 16, 2012
Effective Cycling by Forester is your bible.
posted by Ironmouth at 3:23 PM on June 16, 2012
Your Question 1 is hard to answer because I don't know what you mean by how you refer to the gears. However, if you count the teeth on the chainrings and cogs in question, you can think of them as ratios. Chainring is the numerator, cog is the denominator. Look up "gear ratio" for some more information, or "gear inches" as another way to enumerate the concept. That way, you can not only see if two gear combinations feel the same, but how close to each other they actually are.
I really disagree with Rhomboid's suggestion to favor gear combinations that run the chain as straight as possible. You don't want to be in too high or too low a gear just so that the chain is straight. If you ever play with a bike chain off the bike you will see that it's designed to accomodate a lot of lateral movement.
2. Efficiency: aerodynamics of your body's position on the bike. You can get clip-on aero bars. And, of course, eat properly and hydrate properly, but a 10 or 12 mile ride shouldn't really stress your nutrition or your hydration.
3. Yes.
re: RPMs (revolutions per minute - your cadence), everybody has a different optimal cadence. Some people have the aerobic capacity and the legspeed to prefer high cadences (100+ rpm), and some people have the strength and muscular endurance to prefer (and excel at) low cadences (85 rpm or thereabouts). Being good at both is better.
posted by entropone at 3:37 PM on June 16, 2012
I really disagree with Rhomboid's suggestion to favor gear combinations that run the chain as straight as possible. You don't want to be in too high or too low a gear just so that the chain is straight. If you ever play with a bike chain off the bike you will see that it's designed to accomodate a lot of lateral movement.
2. Efficiency: aerodynamics of your body's position on the bike. You can get clip-on aero bars. And, of course, eat properly and hydrate properly, but a 10 or 12 mile ride shouldn't really stress your nutrition or your hydration.
3. Yes.
re: RPMs (revolutions per minute - your cadence), everybody has a different optimal cadence. Some people have the aerobic capacity and the legspeed to prefer high cadences (100+ rpm), and some people have the strength and muscular endurance to prefer (and excel at) low cadences (85 rpm or thereabouts). Being good at both is better.
posted by entropone at 3:37 PM on June 16, 2012
The difference in your response to the 12 mile ride could be that you have gained some conditioning or that your other physical permutations were more favorable. We change, from day to day.
I don't pretend to have scientific knowledge. I tend to keep the front derailleur in the middle gear, and wander up and down among the 7 available gears. Every once in a while I'll move the front derailleur to the largest sprocket, for more speed.
You will find, as Ironmouth says, that a road bike moves faster. But it is much more sensitive to road conditions. A mountain bike or a hybrid can handle gravel roads. Not a road bike.
posted by yclipse at 3:52 PM on June 16, 2012
I don't pretend to have scientific knowledge. I tend to keep the front derailleur in the middle gear, and wander up and down among the 7 available gears. Every once in a while I'll move the front derailleur to the largest sprocket, for more speed.
You will find, as Ironmouth says, that a road bike moves faster. But it is much more sensitive to road conditions. A mountain bike or a hybrid can handle gravel roads. Not a road bike.
posted by yclipse at 3:52 PM on June 16, 2012
I tend to keep the front derailleur in the middle gear, and wander up and down among the 7 available gears. Every once in a while I'll move the front derailleur to the largest sprocket, for more speed.
I've been talking to a couple bike mechanics about this recently, and I (and they) second Rhomboid's advice.
My notation: 1:1 is the easiest combination of front:rear for climbing.
So, for example, 1:6 feels about the same as 2:3. But 2:3 is better to ride in, because it's easier on your gears and chain and you're less likely to miss gears when changing.
I used to be like yclipse where I'd basically just cycle through 2:1 through 2:7 and avoid using the front derailleur, but I've been told to stop. Now I essentially just use 1:1-4, 2:3-6 and 3:5-7 with some exceptions as needed. It may just be selection bias, but I do feel like a get a bit more out of my bike this way.
posted by no regrets, coyote at 4:05 PM on June 16, 2012
I've been talking to a couple bike mechanics about this recently, and I (and they) second Rhomboid's advice.
My notation: 1:1 is the easiest combination of front:rear for climbing.
So, for example, 1:6 feels about the same as 2:3. But 2:3 is better to ride in, because it's easier on your gears and chain and you're less likely to miss gears when changing.
I used to be like yclipse where I'd basically just cycle through 2:1 through 2:7 and avoid using the front derailleur, but I've been told to stop. Now I essentially just use 1:1-4, 2:3-6 and 3:5-7 with some exceptions as needed. It may just be selection bias, but I do feel like a get a bit more out of my bike this way.
posted by no regrets, coyote at 4:05 PM on June 16, 2012
1) The energy required is the same if the ratio is the same.
Don't worry too much about cross-chaining as people have been discussing. 9 and 10 speed chains have plenty of flex. Small-small (small front chainring and small cog) should be avoided since that can rub on your larger chainring, but large-large (big front chainring, big rear cog) is fine.
2) You will get better/faster! So that first ride really wasn't a good benchmark. Most of my monitoring of my efficiency/effort comes from my heart rate monitor. I have a pretty high heart rate normally, btw. I can cycle for 8-12 hours at 120-130 BPM. Maybe only 6-8 at 140 BPM. At 150-165 BPM I can only keep that up for 3-4 hours without needing to eat way more than I feel like I can carry.
Watching your heart rate can help you manipulate your energy better.
Also, on day-long rides I coast down a lot of hills, tucked until I drop below 15 mph.
3) You will be faster on a road bike. You will be more aerodynamic. Since your torso is flatter, your hips will be rotated forward more, bringing your knees closer to your chest, which all leads to being able to put more power into the pedals.
My nice road bike feels like flying or dancing or wielding some extension of myself, whereas my commuter bike feels, well, very not like that.
posted by MonsieurBon at 6:11 PM on June 16, 2012
Don't worry too much about cross-chaining as people have been discussing. 9 and 10 speed chains have plenty of flex. Small-small (small front chainring and small cog) should be avoided since that can rub on your larger chainring, but large-large (big front chainring, big rear cog) is fine.
2) You will get better/faster! So that first ride really wasn't a good benchmark. Most of my monitoring of my efficiency/effort comes from my heart rate monitor. I have a pretty high heart rate normally, btw. I can cycle for 8-12 hours at 120-130 BPM. Maybe only 6-8 at 140 BPM. At 150-165 BPM I can only keep that up for 3-4 hours without needing to eat way more than I feel like I can carry.
Watching your heart rate can help you manipulate your energy better.
Also, on day-long rides I coast down a lot of hills, tucked until I drop below 15 mph.
3) You will be faster on a road bike. You will be more aerodynamic. Since your torso is flatter, your hips will be rotated forward more, bringing your knees closer to your chest, which all leads to being able to put more power into the pedals.
My nice road bike feels like flying or dancing or wielding some extension of myself, whereas my commuter bike feels, well, very not like that.
posted by MonsieurBon at 6:11 PM on June 16, 2012
1. The only thing that matters is the gear ratio, not how it's arrived at. An engineer can explain how different sprocket combinations that provide the same ratio can be theoretically different in efficiency, and it's not just a question of the lateral displacement of the chain. In the real world, any difference is completely lost in the noise of all the other inefficiencies of the bicycle-human machine and utterly unworthy of attention.
2. Depends what you're trying to achieve. Stamina? Speed? Comfort? Training? Race performance? Which, in turn, inform "efficiency". If you're asking about efficiency in the strictly biomechanical sense, be as aerodynamically inconspicuous as possible, be well rested, be well trained, be disease free, be relaxed and comfortable as possible on a well-fitted bike, lose weight (from the body before worrying about the bike)...
3. The nice road bike will make you faster because it affords a position that makes better use of your physique for turning muscular effort into forward motion, not because it's much lighter. The trick is also to make that position acceptably comfortable.
posted by normy at 6:35 PM on June 16, 2012
2. Depends what you're trying to achieve. Stamina? Speed? Comfort? Training? Race performance? Which, in turn, inform "efficiency". If you're asking about efficiency in the strictly biomechanical sense, be as aerodynamically inconspicuous as possible, be well rested, be well trained, be disease free, be relaxed and comfortable as possible on a well-fitted bike, lose weight (from the body before worrying about the bike)...
3. The nice road bike will make you faster because it affords a position that makes better use of your physique for turning muscular effort into forward motion, not because it's much lighter. The trick is also to make that position acceptably comfortable.
posted by normy at 6:35 PM on June 16, 2012
In addition to questions of performance and efficiency, if you're 52 years old and also doing the running part of a triathlon, you may want to pedal faster in an easier gear in order to reduce stress on your knees. Since you have to put out the same amount of power regardless of how fast you pedal, pedalling more slowly means you have to push harder with each stroke, and that means more stress on your knees. See, for example, an extreme case: link. I would strongly recommend that you err on the side of pedalling faster in an easier gear.
posted by d. z. wang at 6:06 AM on June 17, 2012
posted by d. z. wang at 6:06 AM on June 17, 2012
MonsieurBon wrote: Small-small (small front chainring and small cog) should be avoided since that can rub on your larger chainring, but large-large (big front chainring, big rear cog) is fine.
Emphatically, this is not true. On some bicycles, pedaling vigorously while shifting the chain into the combination of the two largest gears can rip your derailleur off and severely damage the frame in the process. I have personally worked on bikes damaged in this way during my bike shop years. It is especially true if the stock cassette has been replaced with a wider-ratio model, or if the chain has been replaced by someone who expects people to know not to use "crossover" gears.
Look, none of us are qualified to argue with the late, great Sheldon Brown. Rhomboid directed the OP to an excellent resource in the very first answer, and the chain line issue was effectively settled at that point.
posted by richyoung at 8:00 AM on June 17, 2012
Emphatically, this is not true. On some bicycles, pedaling vigorously while shifting the chain into the combination of the two largest gears can rip your derailleur off and severely damage the frame in the process. I have personally worked on bikes damaged in this way during my bike shop years. It is especially true if the stock cassette has been replaced with a wider-ratio model, or if the chain has been replaced by someone who expects people to know not to use "crossover" gears.
Look, none of us are qualified to argue with the late, great Sheldon Brown. Rhomboid directed the OP to an excellent resource in the very first answer, and the chain line issue was effectively settled at that point.
posted by richyoung at 8:00 AM on June 17, 2012
While not scientific, I'd recommend using the 2-2 orientation, if only because it seems to me like it would be a heck of a lot harder to get out of the 1-4 orientation when you needed get back to normal speed.
I have shifters on my downtube, though, so maybe my lack of desire to deal with that hassle is hindering my ability.
Cadence is really really the most important thing to dominating a hill. I did a little googling and I think all this stuff is good reads for the basics.
posted by sibboleth at 9:27 AM on June 17, 2012
I have shifters on my downtube, though, so maybe my lack of desire to deal with that hassle is hindering my ability.
Cadence is really really the most important thing to dominating a hill. I did a little googling and I think all this stuff is good reads for the basics.
posted by sibboleth at 9:27 AM on June 17, 2012
richyoung: Look, none of us are qualified to argue with the late, great Sheldon Brown.
It may be heresy around these parts, but great though he was, Mr. Brown was no engineer and, in my opinion, over- or under-emphasized the importance of some aspects of bicycle mechanics. He's a very good place to start, but not the last word, by any stretch.
sibboleth: Cadence is really really the most important thing to dominating a hill.
I have to strongly disagree. I'm about to argue against generations of received wisdom and millions of words published by bicycling 'experts' (my personal appeal to authority is only several years as a pro mechanic, a mechanical engineering degree and decades of long-distance events).
Cadence is a distracting irrelevance. Your cadence is what it is and it's counter-productive to try to change it. It will naturally increase the fitter and more experienced a bicyclist you become. There is benefit in advising a complete novice to gear down, but once they have the knack of selecting an appropriate gear for themselves, novice (and expert, for that matter) bicyclists should use the gear they feel most comfortable in for the circumstances and give it no more thought.
I believe deliberately attempting to achieve some cadence other that that which your legs feel is appropriate is at best unpleasant and at worst an injury risk. I suspect those that argue in favor of some prescribed cadence (some even advising a particular number) are confusing cause and effect. They see experienced, fit and efficient cyclists generally have a higher cadence than the less fit and experienced and conclude a high cadence is a desirable characteristic to emulate. But the high cadence is a result of their conditioning, not a contributor to their performance.
Any cyclist's cadence is a result of a complex dynamic system with many parameters - their fitness and training, their body fat content, their musculature, the length of their leg bones, the length of their crank, the gear their in, how rested they are, any weight carried on the bike, the gears available to them, their position on the bike, their blood sugar, their hydration, how cold they are... Trying to use a single crude parameter such as cadence to influence performance in such a system seems ridiculous to me.
We (generally) don't tell distance runners to deliberately try to change the length of their stride - it's seen as a result, not a cause, of their conditioning and personal physiology. So, I suggest, it is with bicyclists and their cadence.
posted by normy at 1:20 PM on June 17, 2012 [1 favorite]
It may be heresy around these parts, but great though he was, Mr. Brown was no engineer and, in my opinion, over- or under-emphasized the importance of some aspects of bicycle mechanics. He's a very good place to start, but not the last word, by any stretch.
sibboleth: Cadence is really really the most important thing to dominating a hill.
I have to strongly disagree. I'm about to argue against generations of received wisdom and millions of words published by bicycling 'experts' (my personal appeal to authority is only several years as a pro mechanic, a mechanical engineering degree and decades of long-distance events).
Cadence is a distracting irrelevance. Your cadence is what it is and it's counter-productive to try to change it. It will naturally increase the fitter and more experienced a bicyclist you become. There is benefit in advising a complete novice to gear down, but once they have the knack of selecting an appropriate gear for themselves, novice (and expert, for that matter) bicyclists should use the gear they feel most comfortable in for the circumstances and give it no more thought.
I believe deliberately attempting to achieve some cadence other that that which your legs feel is appropriate is at best unpleasant and at worst an injury risk. I suspect those that argue in favor of some prescribed cadence (some even advising a particular number) are confusing cause and effect. They see experienced, fit and efficient cyclists generally have a higher cadence than the less fit and experienced and conclude a high cadence is a desirable characteristic to emulate. But the high cadence is a result of their conditioning, not a contributor to their performance.
Any cyclist's cadence is a result of a complex dynamic system with many parameters - their fitness and training, their body fat content, their musculature, the length of their leg bones, the length of their crank, the gear their in, how rested they are, any weight carried on the bike, the gears available to them, their position on the bike, their blood sugar, their hydration, how cold they are... Trying to use a single crude parameter such as cadence to influence performance in such a system seems ridiculous to me.
We (generally) don't tell distance runners to deliberately try to change the length of their stride - it's seen as a result, not a cause, of their conditioning and personal physiology. So, I suggest, it is with bicyclists and their cadence.
posted by normy at 1:20 PM on June 17, 2012 [1 favorite]
This thread is closed to new comments.
posted by Rhomboid at 3:19 PM on June 16, 2012