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  1. #1
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    Carry weight on Back or Bike

    Which is better for riding?...carrying your tools, tube, pump, etc. in a Camelbak, thus making the rider heavier and the bike lighter, or fastening these items to your bike, making the bike heavier and the rider lighter. Obviously the total weight is the same, but which of these two options is best for overall riding performance?

  2. #2
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    yea, I have this same question.... I now carry two water bottles in normal cages, and a fanny pack with cell phone, tube, multitool, C02 inflator and keys.... would it be better to switch all these things to a wedge pack in the seat??
    ---(cheap, light, strong)---
    pick two...

    I choose all 3!!!

  3. #3
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    would you rather use up more energy to support that extra weight on youre back/self or let youre bike do it for you.
    do it, do it DO IT!!
    DOOOO IIIIIT!!

  4. #4
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    Quote Originally Posted by BigG
    Which is better for riding?...carrying your tools, tube, pump, etc. in a Camelbak, thus making the rider heavier and the bike lighter, or fastening these items to your bike, making the bike heavier and the rider lighter. Obviously the total weight is the same, but which of these two options is best for overall riding performance?
    I would guess it is probably best to carry extras as low as possible in an attempt to lower the overall centre of gravity......

  5. #5
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    Try and hold a 20lb backpack by your hands with your arms outstretched for a few hours.

    Now put the backpack on.

    Big difference.

    The further the mass is from your body (the center of rotation), the more force you will need to supply.

    This is why a heavier bike fatigues you more not only in terms of pedaling, but over your entire body.
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

  6. #6
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    Same question...

    Quote Originally Posted by BigG
    Which is better for riding?...carrying your tools, tube, pump, etc. in a Camelbak, thus making the rider heavier and the bike lighter, or fastening these items to your bike, making the bike heavier and the rider lighter. Obviously the total weight is the same, but which of these two options is best for overall riding performance?
    I've been wondering the same thing. It seems like having the weight on your back would help handling alot because you can more easily bunnyhop, wheelie and throw the bike around. I have also read that a heavier bike downhills better. At the same time, I see the point about letting the bike carry the weight, but also the point about holding your arms outstretched... in climbing, they say "A pound on the feet is like five on the back." Which means heavy boots will run you down. But a bike is not boots. The bike does hold the weight but it also must be pushed to accelerate. The water isn't held on the wheels. The body must be pushed to accelerate too. Is there a physics major in the house?

    One thing I think about Camelbaks is: What a pain in the as*. A bottle is so easy to clean, etc. I like to keep it simple so I would love to think that a Camelbak will not help my riding skills. But my riding skills need help.

    What's the deal?

  7. #7
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    Quote Originally Posted by Jm.
    The further the mass is from your body (the center of rotation), the more force you will need to supply.

    This is why a heavier bike fatigues you more not only in terms of pedaling, but over your entire body.
    If the problem was 3D then that might be true, but it's not as virtually all force in normal biking is forward acceleration. In such scenarios is does not make a difference where the weight is as long it's only accelerated forward.

  8. #8
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    i work on this rule.

    if the course your riding has any sections that you may have to get off and push/carry your bike then put the weight on your back, it's much easier to carry the bike without the extra weight where as you don't really notice the weight difference sitting on your back.

    if the course if fairly easy/long such as a marathon race or fire road point to point then put the weight on your bike, you won't be getting off to push so won't notice the extra weight and it won't annoy you bouncing around on your back.

    just a note, the only time i use a camelback is if a racecourse is predominately singletrack with not much time to get a drink using a bottle. i think i use one once a year on average, the weight i'm talking about shifting from rider to bike or vice-versa is only tools/tubes/food, i always use a bottle for my drinks.

    cya, john.

  9. #9
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    I agree with the putting it on your camelback theory for a few reasons. First off, someone said that it helps you throw the bike around and bunny hop and such. This is absolutely true, and is a HUGE advantage in XC racing. Also I tend to carry a minitool, CO2 cartridge and tube in addition to water in there, so it kindof easier to carry in a camelback. Also, as aussie yeti said, on a technical course its almost impossible to drink for a water bottle. Finally, I don't really think you get fatigued by having the weight on your back.

    Or if it does fatigue you, I feel that having the extra 5 lbs of water/tools on your bike and having to deal with that would fatigue you much more.

  10. #10
    Jm.
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    Quote Originally Posted by BlackCat
    If the problem was 3D then that might be true, but it's not as virtually all force in normal biking is forward acceleration. In such scenarios is does not make a difference where the weight is as long it's only accelerated forward.
    Still wrong.

    Bend over and try to push a 50lb block on the floor with your arms, don't bend your knees.

    Now do the same with the 50lb block at chest level, on a counter or something. You get more leverage eh? To accellerate that mass, the further away it is from your body the harder it is. And not all accellerations are forward, you get upwards and downwards (especially at the pedals and handlebars) and you get lots of side to side, changing direction isn't effortless even though it may seem so at times, it actually requires you to input a force, as Newton found out. Any time you change direction, you are imparting a force to do so. The further away that force is from your body, the more torque it takes to do so, and the more force has to be supplied due to leverage. The problem is 3d, it's just that most people are not open-minded enough to see that it is.
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

  11. #11
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    Aside from the laws of gravity/motion (I think Jm.'s correct), Camelback nipples ride a lot further from trail debris than water bottle openings, not to mention the "rattle" of seat bags.

  12. #12
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    source for bottle to fit in jersey

    Quote Originally Posted by BigG
    Which is better for riding?...carrying your tools, tube, pump, etc. in a Camelbak, thus making the rider heavier and the bike lighter, or fastening these items to your bike, making the bike heavier and the rider lighter. Obviously the total weight is the same, but which of these two options is best for overall riding performance?
    I need to carry 2 bottles in a race, but my bike only has 1 bottle mount. I plan on carrying the 2nd bottle in my jersey. Are there any bottles that are flatter and would fit better against the back? Like a big plastic flask.

    BTW, for MTB I think it is better to carry the water on the rider because it makes no difference when climbing, but it helps to have a lighter bike in just about all other areas because the bike is moved around more than the rider. That said it is rather inconvenient to carry water on the body. The only sensible location is near the lumbar area as all other parts of the body need to move freely. Camelbaks are strapped on restricting motion, breathing and cooling and add weight.
    M

  13. #13
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    While I totally agree with Jm, I'm still not certain which is better in a race situation.

    I use one of the lighter Camelbaks which is the Hydrabak (holds 1.5L and is low profile)and it weighs 391g empty. Let's say for example, you drink 1.5L in a 1 1/2 hour XC race... then that needs to all go in before you start since there won't be any refills during a race ..so that's 391g + 1500g = 1891g which you start the race with.

    On the other hand, a typical water bottle cage is about 30g plus a bottle that holds 500ml may weigh about 70g. So 100g + 500g of water = 600g ...less than a third of the weight. The key here is that usually you don't need to drink anything on the first lap so many riders start the race with only an empty cage ...so for example in a 4 lap race ...the bottle racers carry 30g for that first lap and the Camelbak guys carry almost 2kg.

    If the bottle guys need to drink the same 1.5L of water for that 4 lap race ...they can get the first bottle passed to them at the beginning of the second lap ...drink it during the lap ...throw empty or mostly empty bottle at end of second lap ...take next bottle for the third lap and so on ....so at no point in the race is the bottle racer carrying more than 600g

    I agree that it is definitely more convenient to drink from a Camelbak since even in technical areas you can drink but I do think that it may restrict body movement, breathing and cooling to some extent.

    That first lap situation may be something to think about though when everyone is jockeying for position.

  14. #14
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    Quote Originally Posted by eurorider
    While I totally agree with Jm, I'm still not certain which is better in a race situation.

    I use one of the lighter Camelbaks which is the Hydrabak (holds 1.5L and is low profile)and it weighs 391g empty. Let's say for example, you drink 1.5L in a 1 1/2 hour XC race... then that needs to all go in before you start since there won't be any refills during a race ..so that's 391g + 1500g = 1891g which you start the race with.

    On the other hand, a typical water bottle cage is about 30g plus a bottle that holds 500ml may weigh about 70g. So 100g + 500g of water = 600g ...less than a third of the weight. The key here is that usually you don't need to drink anything on the first lap so many riders start the race with only an empty cage ...so for example in a 4 lap race ...the bottle racers carry 30g for that first lap and the Camelbak guys carry almost 2kg.

    If the bottle guys need to drink the same 1.5L of water for that 4 lap race ...they can get the first bottle passed to them at the beginning of the second lap ...drink it during the lap ...throw empty or mostly empty bottle at end of second lap ...take next bottle for the third lap and so on ....so at no point in the race is the bottle racer carrying more than 600g

    I agree that it is definitely more convenient to drink from a Camelbak since even in technical areas you can drink but I do think that it may restrict body movement, breathing and cooling to some extent.

    That first lap situation may be something to think about though when everyone is jockeying for position.
    Boy, you really though this thing out! Personally, I have always ben amazed at the popularity of the hydration packs. While I do own 2 of them and I'll admit they are handy at times, I only use them if 2 bottles and a seat pack won't carry what I need. Why the heck should I carry that hot uncomfortable thing all day on my back when my bike can do the work? I even resort to adding a dorky looking handlebar bag at times rather than break out the camelback. They really ought to call them sweatybacks if you ask me. That's my opinion, make it yours!

  15. #15
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    Quote Originally Posted by cyclust
    Boy, you really though this thing out! Personally, I have always ben amazed at the popularity of the hydration packs. While I do own 2 of them and I'll admit they are handy at times, I only use them if 2 bottles and a seat pack won't carry what I need. Why the heck should I carry that hot uncomfortable thing all day on my back when my bike can do the work? I even resort to adding a dorky looking handlebar bag at times rather than break out the camelback. They really ought to call them sweatybacks if you ask me. That's my opinion, make it yours!
    I almost never use camelbacks, I have one sitting at home, but my coach was always bugging me to use it for long, hot races. All you have to do is fill it up about half way, freeze that overnight, and it keeps your back very cool, reducing your core temperature. I tried it a couple of times, never really liked it though because its akward and uncomfortable, but i'm just letting you know incase you want to try it. Plain old bottles for me...

    And I always carry stuff on my back during races. Chain break, multi tool, co2 pump and tube in my back pockets.
    (8) climb hard or never be seen (8)

  16. #16
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    and

    Quote Originally Posted by eurorider
    While I totally agree with Jm, I'm still not certain which is better in a race situation.

    I use one of the lighter Camelbaks which is the Hydrabak (holds 1.5L and is low profile)and it weighs 391g empty. Let's say for example, you drink 1.5L in a 1 1/2 hour XC race... then that needs to all go in before you start since there won't be any refills during a race ..so that's 391g + 1500g = 1891g which you start the race with.

    On the other hand, a typical water bottle cage is about 30g plus a bottle that holds 500ml may weigh about 70g. So 100g + 500g of water = 600g ...less than a third of the weight. The key here is that usually you don't need to drink anything on the first lap so many riders start the race with only an empty cage ...so for example in a 4 lap race ...the bottle racers carry 30g for that first lap and the Camelbak guys carry almost 2kg.

    If the bottle guys need to drink the same 1.5L of water for that 4 lap race ...they can get the first bottle passed to them at the beginning of the second lap ...drink it during the lap ...throw empty or mostly empty bottle at end of second lap ...take next bottle for the third lap and so on ....so at no point in the race is the bottle racer carrying more than 600g

    I agree that it is definitely more convenient to drink from a Camelbak since even in technical areas you can drink but I do think that it may restrict body movement, breathing and cooling to some extent.

    That first lap situation may be something to think about though when everyone is jockeying for position.
    Clearly water bottles are the lightest solution. But you assume there is someone willing to do water bottle exchanges for you. I personally would never even ask someone to do that because it is booring. Another factor in favor of bottles is that each can have different contents. I like to have 1 with water and 1 with energy/electrolyte drink.

    I do have issues with bottles though. My FS frame only has a mount for 1 bottle and it is kinda low. FS frames with 2 bottle mounts usually put the second one on the bottom of the downtube which is almost dangerous to access. Round bottles do not fit well in jersey pockets and full water bottles drag my jersey around.
    M

  17. #17
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    Quote Originally Posted by eurorider
    While I totally agree with Jm, I'm still not certain which is better in a race situation.
    .
    I can definitely agree with that. Races are often only a couple hours, and it's true that the camelback is usually going to be heavier than an equivalent amount of water in bottles (and you usually find more important stuff to put in a camelback like phone, tools, pump, tube, etc). So there may be a discontinuity where you may be able to ride with more water and while it may benefit your body some, the advantage of having a little less water and a little less weight may outweight it. It's not going to be set in stone though and it will probably pull both ways depending on the exact circumstance.

    A lot of people that "only need" one or two water bottles may simply not ride to the same length and endurance as others that need more than 100oz for a ride. When the temp gets up there or you are out all day, 100oz sometimes just doesn't cut it and during the warm season (I don't live in phoenix but close enough that we get into the 90s with extremely low humidity) 200oz can be used up completely on a "multi-hour epic" ride. Try putting 130-200oz of water on your bike. I think you'd notice a HUGE difference. This is where the fact that the mass is fairly far away from your body's center makes a huge difference. Being that you can strap 130-200oz right onto your back, and have your back support it just as if it was additional weight on your body, it simply doesn't fatigue you nearly as much as the 15lb of aditional weight on your bike would.

    When we talk about this senario we also sometimes assume that "weight off the person" is all fat and that the overal fitness and muscle strength of the individual is improved. If we increaes our fitness, then we are going to be obviously faster, however I submit that when looking at the sheer physics of having 10lb of weight securly strapped to your upper body so that it is as close to your body as possible, compared to having a bike that has a 10lb heavier frame, or wheels, or whatever, the 10lb on the bike is going to make a much bigger difference.

    If you want instant gratification and results, shift weight off the bike and onto your body, if you want to be more fit (and therefore faster as well), then excersise more obviously. Physics supports the fact that the weight off the bike is more important from a torque standpoint. Physiology supports the fact that if you excersise more and loose weight you'll probably be faster and more in shape, although this can be taken to a limit.
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

  18. #18
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    I had that question about a week ago and my friend told me about "sprung and unsprung weight"

    Sprung - meaning your body supports the weight
    Unsprung - meaning the bike supports the weight

    it kinda sounds like what JM is talking about

  19. #19
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    Whatever works best for the rider is.....

    clearly the right solution. I think of it this way. I'd rather stand and sprint on a 24 pound bike while wearing a 20 lb. pack than try to stand and pedal a 44 pound bike wearing no pack.






    Quote Originally Posted by BigG
    Which is better for riding?...carrying your tools, tube, pump, etc. in a Camelbak, thus making the rider heavier and the bike lighter, or fastening these items to your bike, making the bike heavier and the rider lighter. Obviously the total weight is the same, but which of these two options is best for overall riding performance?

  20. #20
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    Quote Originally Posted by HellMuttCracker
    I had that question about a week ago and my friend told me about "sprung and unsprung weight"

    Sprung - meaning your body supports the weight
    Unsprung - meaning the bike supports the weight

    it kinda sounds like what JM is talking about
    Sprung and unsprung weight is a diferent subject altogether and would only apply to a suspension bike.
    Unsprung weight is any mass that is not supported by the spring/shock, such as wheels/tires, swing arms, the portion of the fork that moves up and down ect. Generaly the less unsprung weight the better the handling. This is why some manufacturers of forks are inverting them so the sliders are on the bottom of the fork rather than the top. look at a Maverick fork.
    Sprung weight would include anything that is supported by the suspension which includes the main frame, the rider, and anything attatched to either of the two.
    that's my two cents on that subject.

  21. #21
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    While I agree with you, I think HellMuttCracker has a point. At least the easiest to understand so far. Pretend you are on a rigid bike, then what he said would be 100% accurate. Even on a FS bike, and XC bikes are generally on the lower end of the travel range, the rider's body english plays a HUGE part in the bikes handling and bump abosorbtion. Even though I ride a FS, I still get out of the saddle when going big rocks and whoops, to soak it up with my arms and legs. In that instance, my body is acting like a secondary suspension. Your argument is 100% true, and applies 100% to a vehicle like a car where the passengers and drives don't take an active role in helping the vehicle negotiate terrain.

    Honestly, I didn't take this thread seriously when I first read it, but some have made some really impressive arguments. I'm still not wearing a camelback though! Unless, of course, I end up doing some real long distance rides...
    "I've come to believe that common sense is not that common" - Matt Timmerman

  22. #22
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    Quote Originally Posted by MantisMan
    clearly the right solution. I think of it this way. I'd rather stand and sprint on a 24 pound bike while wearing a 20 lb. pack than try to stand and pedal a 44 pound bike wearing no pack.
    Too bad that it won't help you one bit to spring faster. It won't matter if it's on your back, if it's in a basket on the front, on the rear, or a pole that is 30 feet long extending in any direction with the weight on the end.

    And if anything, assuming you are heavy enough to put down a pedal while standing up without a weight on your back, you will only lose energy by supporting that extra weight with your legs.
    Last edited by BlackCat; 02-01-2005 at 11:38 AM.

  23. #23
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    always want to carry the weight lower, lower center of gravity and better handling,not up high like on a camel back. the further the weight is from the center of the bike, the greater the moment is and the 5lbs of water acts alot heavier.

  24. #24
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    All about convenience

    I use my camelbak for short rides too. I keep it packed with my mini-pump, tools, etc so when I want to ride all I have to do is fill it up with water and go. If I use bottles, frame packs and jersey pockets then I have more stuff I have to pack/unpack, and a bigger chance of forgetting something.

    I've never noticed problems with breathing or shifting with my camelbak; heat/sweat can be annoying but I don't really notice it anymore. I definitely noticed the noise of my frame pack banging around, and I remember dropping a couple of larger water bottles from weak cages.

  25. #25
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    Quote Originally Posted by BlackCat
    Too bad that it won't help you one bit to spring faster. It won't matter if it's on your back, if it's in a basket on the front, on the rear, or a pole that is 30 feet long extending in any direction with the weight on the end.

    And if anything, assuming you are heavy enough to put down a pedal while standing up without a weight on your back, you will only lose energy by supporting that extra weight with your legs.

    Not true- a 44lb bike will have heavy parts such as fatty tires and big cranks/wheels. Rotating mass plays the LARGEST factor when it's time to get up and go. That's why lighter bikes "feel" faster, and ultimately why we all talk about them on this forum.
    A hardtail is forever

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    Quote Originally Posted by Hardtailforever
    Not true- a 44lb bike will have heavy parts such as fatty tires and big cranks/wheels. Rotating mass plays the LARGEST factor when it's time to get up and go. That's why lighter bikes "feel" faster, and ultimately why we all talk about them on this forum.
    I'm surprised you didn't bring up the weight and air drag of the hypothetical 30 foot pole
    Last edited by BlackCat; 02-01-2005 at 11:28 PM.

  27. #27
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    Quote Originally Posted by BlackCat
    Too bad that it won't help you one bit to spring faster. It won't matter if it's on your back, if it's in a basket on the front, on the rear, or a pole that is 30 feet long extending in any direction with the weight on the end.
    Wrong. Acellerating a mass 30 feet from your bike (which is what you try to do with every pedal stroke in that situation) is going to be MUCH harder than if the equivalent weight is strapped to your back.

    Seriously, do you simply not understand torque and leverage?
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

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    Quote Originally Posted by Jm.
    Wrong. Acellerating a mass 30 feet from your bike (which is what you try to do with every pedal stroke in that situation) is going to be MUCH harder than if the equivalent weight is strapped to your back.

    Seriously, do you simply not understand torque and leverage?
    I understand it perfectly, and only after some college physics classes many years ago. Do I need to draw you a picture?

    Even better, look at your avatar, maybe visually this will work better.

    It's a bike with a basket on the rear. Do you think you'll accelerate slower if the basket was on the front? What about it being 5 feet in front of the bike? 5 feet in the back? Would you go slower then? What about 500 feet in the back or front? Will you even be able to move the bike then?

  29. #29
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    Or how about 2 basket to either side of you 10 feet away each? Will you accelerate any slower than if those 2 baskets were on your back? ABSOLUTLY NOT. It would not make any difference whatsoever.

    Take a look at the diagram. If you think that the UPWARD directional force applied to lift any of those combined weights is different, then this all has been a waste of time. And your bike also only exerts directional FORWARD force through that little contact patch between the drive wheel and ground.
    Attached Images Attached Images

  30. #30
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    Leverage...

    But it's about leverage too. I don't really have a clear idea here but it seems like leverage comes into play. I know that if you carry five pounds of weight on your feet it is much harder than if you carry it on your back. Might this relate to carrying the weight on your bike?

    Like if you were trying to hold those weights out from your body and then accelerate. It would be harder than if you didn't have to use extra muscle effort to hold the weights.

    But then there is the fact that you have to support the weight with your legs.

    What takes more effort? Supporting the weight with your legs(Camelbak), or accelerating the weight on the bike--away from your body(Bottle)?

  31. #31
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    Thought experiment....

    Say you are a touring cyclist....

    Do you buy panniers and racks, or just wear a full sized backpack and carry your gear
    in that?



    Say you need to move a load of bricks....

    Do you carry them in your arms so that they "are close to your center of gravity"
    or do you put them in a wheelbarrow?

    ZB
    No hairSShirts.

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    That would change things.

    I think the situation would change if the amount of weight was so great that it was a huge burden to carry it.

    There must be a compromise between having to accelerate the weight and having to carry the weight. At some point, it would definitely be harder to carry the weight.
    Last edited by grumpstumper; 02-02-2005 at 12:20 PM. Reason: I never wun no spellin bees.

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    Quote Originally Posted by grumpstumper
    But it's about leverage too. I don't really have a clear idea here but it seems like leverage comes into play. I know that if you carry five pounds of weight on your feet it is much harder than if you carry it on your back. Might this relate to carrying the weight on your bike?

    Like if you were trying to hold those weights out from your body and then accelerate. It would be harder than if you didn't have to use extra muscle effort to hold the weights.

    But then there is the fact that you have to support the weight with your legs.

    What takes more effort? Supporting the weight with your legs(Camelbak), or accelerating the weight on the bike--away from your body(Bottle)?
    Take 2 bottles in each hand, and extend them to your sides. Now run forward. Now think, why would the 2 bottles to your sides slow you down more than if they were in your backpack?

    The answer is simple, they would not. Your hands will move back slightly as they obviously have joints, and that is it. Don't confuse the energy to keep your arms up in the air and keeping them to your sides with the energy that will be used to make you go forward.

    This is extremely simple and does not require any physics, just basic logic and reasoning.

  34. #34
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    Weight Weenie F.A.Q.'s

    This is from the Weight Weenie FAQ's:

    6. Why not shed some weight of my body rather then the bike?
    Loosing weight is a good thing if you need to (ie Over weight), but loosing weight off a bike is great for several reasons:
    Bike feels more responsive
    Bike becomes more nimble
    Rotational weight is reduced which can be beneficial to acceleration
    Bike is easier to get up climbs etc (Why burn energy riding a heavy bike up a hill?


    Just some side thoughts for the subconscious mind.

  35. #35
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    Heart rate.

    Your heart rate would reach it's max faster if you were holding the bottles out.

  36. #36
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    Well all that depends of the alignment of the planets and what phase the moon was in...
    "I've come to believe that common sense is not that common" - Matt Timmerman

  37. #37
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    grumpstumper, you meant to say holding the camel with your back

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    Any suggestions on an ultra light Camelback?

    I've been looking for an ultra light 50ozer just big enough for a mini pump & flat essentials.
    I've considered the fanny pack hydration pack.

    Right now I'm doing the one bottle in the waist/fanny pack and one bottle on the frame, working out pretty good and for long epic non racing rides I just fill up the Mule and try to drink a lot in the begining of the ride.

  39. #39
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    Ok -

    Well, according to some theories here, all that matters is how far the stuff is from your
    center of gravity. I think that's a bunch of hooey.

    My point is that your body doesn't see work the same way physics does. Your body
    fatigues and burns calories even just SUPPORTING a load - no motion necessary.

    So the thing about strapping stuff to your body is that you are ALWAYS working to support
    it - even when you are going straight and level, even if you are stopped, even if it is not a "huge burden". So you have to work to a) accelerate the crap, and b) hold the crap up.

    When the stuff is strapped to your bike, the only time you have to work is to a) accelerate
    the crap.

    One thing I know for sure - I've done endurance length events with and without a Camelback, and there is no way in hell I'll ever carry one again if I can at all get away
    without it.

    I submit that any difference due to "distance from your center of gravity" is far outweighed
    by physically having to hold your crap up off the ground.

    One day I may get bored enough to try to mathematically prove myself right or wrong....
    but I doubt it.

    Sure is fun to rant about on the 'net, though.
    ZB
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  40. #40
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    Bottles/Camelback.

    Quote Originally Posted by BlackCat
    grumpstumper, you meant to say holding the camel with your back
    But the camelbak is closer to your body than the bike/bottles.

    Don't get me wrong. I don't know. I'm just exploring the idea trying, to find out. I use bottles now, but I was wondering why so many people use Camelbaks. It would be handy to be able to pack my extra layers when I take them off, and nice for long rides. Can you just use the thing without the water flask--as a pack?

  41. #41
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    Quote Originally Posted by BigG
    Which is better for riding?...carrying your tools, tube, pump, etc. in a Camelbak, thus making the rider heavier and the bike lighter, or fastening these items to your bike, making the bike heavier and the rider lighter. Obviously the total weight is the same, but which of these two options is best for overall riding performance?
    After 30 something replies, something not said yet...

    IMHO It depends on how much you ride out of the saddle.

    If you climb out of the saddle alot, then you should have the weight on your back. It's weight will help you on the downstroke every time.

  42. #42
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    Quote Originally Posted by Juan Speeder
    After 30 something replies, something not said yet...

    IMHO It depends on how much you ride out of the saddle.

    If you climb out of the saddle alot, then you should have the weight on your back. It's weight will help you on the downstroke every time.
    good point but I think it's the other way around ...if you are out of the saddle often, then you WOULDN'T want a camebak since that is extra weight your legs must support and it will hinder your body english

    I'd say the worst time to use a camelback would be on a fully rigid, followed by a hardtail followed by a full-suspension ....it could be said that full-suspension riders stay seated the longest and have the least amount of body english so the camelbak is less of an issue but even then, the water bottle route is likely superior

    anyways, I'd agree with what brewSSard said

  43. #43
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    Quote Originally Posted by Jm.
    And not all accellerations are forward, you get upwards and downwards (especially at the pedals and handlebars) and you get lots of side to side, changing direction isn't effortless even though it may seem so at times, it actually requires you to input a force, as Newton found out. Any time you change direction, you are imparting a force to do so. The further away that force is from your body, the more torque it takes to do so, and the more force has to be supplied due to leverage. The problem is 3d, it's just that most people are not open-minded enough to see that it is.
    However, when the weight is on your body, not only is that weight moving when the bike moves, but it moves every time your body moves independently from the bike. Seems to me that this could be significant. All your subtle weight shifts, standing, sitting back down, every time you move your body, you're having to move that weight. Whereas when the weight is on the bike, it's only moving when the bike is moving. That said, I always ride with a hydration pack because I find it much easier to drink on the fly and I stay much better hydrated.
    "The question before the human race is, whether the God of nature shall govern the world by his own laws, or whether priests and kings shall rule by fictitious miracles."
    John Adams to Thomas Jefferson, 1815

  44. #44
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    Exactly....

    That's what is so interesting about the debate. I see Jm's point, but disagree with the
    significance of the effect he is describing.

    Jm - jump in here if I'm wrong, but I'd like to put forward an analogy illustrating your point -
    Ya'll have seen the tight-rope walkers? You know how they hold a long pole in their hands
    with weights way out at the far ends? The reason they carry that pole is that if they start
    to fall, they can push against the pole's inertia to regain balance. The pole won't move
    much because the walker doesn't have the leverage to move the weights that are way the
    heck out there. They can push hard against it and it won't move a lot. If they weight were
    right in their hands, they'd fall right over. Same thing with Jm's point about leverage on the
    bike. If the weight is far away, it's harder to move. So what I get from that arguement is
    that in technical situations when moving the BIKE is important, you want a light bike with
    the weight on the rider. BUT - I would say that in an endurance / racing situation when
    moving the ENTIRE BIKE-RIDER SYSTEM is most important that having the weight on
    the bike is preferable. For my reasoning on this, see my posts below about the bricks,
    backpacks, and how the body perceives work. That's where I agree with jcw.

    Anyway, before reading all of this I would have said that bottles win all the time hands
    down. Jm's point opens the possibility in my mind that a pack might theoretically be
    better in some situations. I doubt it, but I'm not going to take my d*ck out about it
    because I'm far to lazy to bother trying to run the numbers, and if I can't put up, I'll shut
    up and admit the possiblity that he's right. The only reason I weigh in on this debate is
    that it rankles when something that is not absolute gospel is put forth as such. Anyhow,
    somebody here said to run whatever you like, and I say hallelluia to that.

    Fun debate.

    ZB

    Quote Originally Posted by jcw
    However, when the weight is on your body, not only is that weight moving when the bike moves, but it moves every time your body moves independently from the bike. Seems to me that this could be significant. All your subtle weight shifts, standing, sitting back down, every time you move your body, you're having to move that weight. Whereas when the weight is on the bike, it's only moving when the bike is moving. That said, I always ride with a hydration pack because I find it much easier to drink on the fly and I stay much better hydrated.
    No hairSShirts.

  45. #45
    Jm.
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    Quote Originally Posted by BlackCat
    Or how about 2 basket to either side of you 10 feet away each? Will you accelerate any slower than if those 2 baskets were on your back? ABSOLUTLY NOT. It would not make any difference whatsoever.

    Take a look at the diagram. If you think that the UPWARD directional force applied to lift any of those combined weights is different, then this all has been a waste of time. And your bike also only exerts directional FORWARD force through that little contact patch between the drive wheel and ground.
    You've used the wrong illustrations and examples.

    Which one of the following is going to be harder to hold? Why? With any kind of accelleration, the fact that the weight is further from your body will simply take more energy to support and change the direction of it.
    Attached Images Attached Images
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

  46. #46
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    Quote Originally Posted by Jm.
    You've used the wrong illustrations and examples.

    Which one of the following is going to be harder to hold? Why? With any kind of accelleration, the fact that the weight is further from your body will simply take more energy to support and change the direction of it.
    It will take the same amount of force to move your 10lb buckets. Pull it to the left, push it to the right.

    What you suggesting is spinning the bucket in free space about the point of where the hand is, and that does not in any shape or form represent or have any similarity to what is happening when a bicycle accelerates.
    Attached Images Attached Images

  47. #47
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    Quote Originally Posted by BlackCat
    It will take the same amount of force to move your 10lb buckets. Pull it to the left, push it to the right.

    What you suggesting is spinning the bucket in free space about the point of where the hand is, and that does not in any shape or form represent or have any similarity to what is happening when a bicycle accelerates.
    Well, you are forgetting about the fact that you are constantly accellerating a bike, each pedalstroke, etc, it's not smooth power transfer, it's lots of accellerations basically.

    So what some people can't grasp is that your center of mass is the center for these accellerations, and it's like a spinning wheel because you are constantly trying to acellerate mass that is away from your "center of rotation". There's no centripital force to force the mass to move in a circle, but it's like constantly "intitially acellerating" a mass.

    I wasn't talking about "pushing" the weight, I was talking about holding it, that means that it's being accellerated (by gravity), so if it's closer to your body, it requires less energy to "hold it up" than is required when it's further from your body. When you are on the bike, the same applies, to acellerate the wheel, or the fork, or the quick release lever, you must apply a force, and since those items are far from your center of mass, it requires more energy to acellerate them. This only holds true of course when you consider the CENTER OF MASS, but when they are being acellerated (which happens all the time) there is most definitly a center of mass an center of rotation.
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

  48. #48
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    Quote Originally Posted by Jm.
    Well, you are forgetting about the fact that you are constantly accellerating a bike, each pedalstroke, etc, it's not smooth power transfer, it's lots of accellerations basically.

    So what some people can't grasp is that your center of mass is the center for these accellerations, and it's like a spinning wheel because you are constantly trying to acellerate mass that is away from your "center of rotation". There's no centripital force to force the mass to move in a circle, but it's like constantly "intitially acellerating" a mass.

    I wasn't talking about "pushing" the weight, I was talking about holding it, that means that it's being accellerated (by gravity), so if it's closer to your body, it requires less energy to "hold it up" than is required when it's further from your body. When you are on the bike, the same applies, to acellerate the wheel, or the fork, or the quick release lever, you must apply a force, and since those items are far from your center of mass, it requires more energy to acellerate them. This only holds true of course when you consider the CENTER OF MASS, but when they are being acellerated (which happens all the time) there is most definitly a center of mass an center of rotation.
    I'm certainly not going to try to decipher that paragraph as I'm certain that it does not contain anything that disproves any of the basic laws modern physics holds as true. You win the prize.

  49. #49
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    I refute it thus -

    So what some people can't grasp is that your center of mass is the center for these accellerations, and it's like a spinning wheel because you are constantly trying to acellerate mass that is away from your "center of rotation". There's no centripital force to force the mass to move in a circle, but it's like constantly "intitially acellerating" a mass.

    I wasn't talking about "pushing" the weight, I was talking about holding it, that means that it's being accellerated (by gravity), so if it's closer to your body, it requires less energy to "hold it up" than is required when it's further from your body. When you are on the bike, the same applies, to acellerate the wheel, or the fork, or the quick release lever, you must apply a force, and since those items are far from your center of mass, it requires more energy to acellerate them. This only holds true of course when you consider the CENTER OF MASS, but when they are being acellerated (which happens all the time) there is most definitly a center of mass an center of rotation.[/QUOTE]



    If I'm using a rope to pull something up to the roof, the load doesn't get easier to pull as
    it gets closer to me. Why not? The load is getting closer to my center of mass. If you
    want to talk acceleration, we can do that too. Does the load get easier to accelerate as
    it gets closer to me? Your missing a ton of real world nuance with this gross over-
    simplification.... to paraphase your snide remark to someone up thread - do you know
    anything about vectors? Do you have any comments about why touring cyclists don't
    carry backpacks?

    ZB
    No hairSShirts.

  50. #50
    Jm.
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    Baseball.

    If you try to throw a baseball, does it feel "heavier" when it's closer to your body, or further? It's not the same, and the further it is from your body, the more force you must impart on it, because for that second that you are accellerating it, it is attached to your body obviously. Find something heavy and try this.

    You keep trying to say that we are talking about linear forces and movement, but the forces on a bike are anything but.
    Last edited by Jm.; 02-03-2005 at 07:17 AM.
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

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