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  1. #1
    Real Human Being wild animals's Avatar
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    Going Downhill--FAST

    Hi guys,

    I am a bigger person and yesterday I climbed a heinous hill. I think it may actually be a mountain but I'm not sure. Anyway, I then had to go down the hill. I was going 26mph with the brake levers cranked back almost all the way, and when I wanted to stop, it took a looong time. I had to stop a number of times to let the brakes cool off. I considered walking. It was really scary, because there is gravel and the road is really curvy. Usually I like (love) going downhill fast but this was too much. I tried braking-coasting-braking, but I couldn't keep myself at a safe speed that way.

    What can I do to improve this situation?! Aside from losing weight, obviously?

    I have a 2008 Jamis Aurora touring bike with "Tektro cantilevers." I got the bike a year and a half ago and maybe should get new brake pads(?).

    Thanks!
    Go until you stop, then take a break.

  2. #2
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    Wow!
    I would have been scared s*tless!
    I have been thinking about crossing a bridge in my area, but have been worried about the downhill trek for this very reason.

  3. #3
    Senior Member CollectiveInk's Avatar
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    Definitely check for brake wear. As clydes, we tend to put a little more wear and tear on the pads. Also, if they are the stock pads, those "typically" aren't very good anyway. There are some great ones out there. You can find some for disssipating heat as well as stopping power. I actually run two different pads for the front and rear.

    There was a bit of sticker shock at first (I mean, come on they're only little rubber brake pads, right?) but then I realized, even the best brake pads are cheaper than a trip to the ER.

    Also check your brake cable tension. After some serious downhill stops they could have stretched some and you'll need to take up the slack.
    Tim
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  4. #4
    Real Human Being wild animals's Avatar
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    CollectiveInk, GREAT! Thanks! I was worried it might be a "time for disc brakes" situation. Haha I think I am going to put it in the shop for a tune-up anyway so that would be perfect. Which type do you use on the front and on the rear?

    TallStevens, what is the hill like on your bridge? I think the fastest I've ever gone was around 40(?) down a hill near my house, and it was kind of scary but mostly awesome, because it was perfectly straight, no gravel, and no trees--perfect visibility. Maybe your hill is like that? (I hope!) The hill yesterday took me like an hour to go up, and I think 10 minutes to go down, not counting breaks. haha.
    Go until you stop, then take a break.

  5. #5
    Mystery Meat gitarzan's Avatar
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    I wish I had that situation. I live on q gentle crest between a creek and a river. No matter where I go, homebound is uphill.
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  6. #6
    Real Human Being wild animals's Avatar
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    Uggh, I'm sorry. I was thinking how nice it is that wherever I get tired, all I have to do is turn around and roll. A lot of the people along those roads have driveways that go up or downhill in some crazy way, and I was thinking how hard it'd be to force myself to ride my bike if I lived there. I'd have to drive up to the street first.
    Go until you stop, then take a break.

  7. #7
    foolishly delirious RatedZeroHero's Avatar
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    we had the same dilema living in Littleton CO last year...
    no matter which way we went... it was either uphill or downhill on the return...
    same as leaving... kids were in great shape last year!

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    Fresh Garbage hairnet's Avatar
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    Quote Originally Posted by wild animals View Post
    Hi guys,

    I was going 26mph with the brake levers cranked back almost all the way, and when I wanted to stop, it took a looong time.

    the road is really curvy. Usually I like (love) going downhill fast but this was too much. I tried braking-coasting-braking, but I couldn't keep myself at a safe speed that way.
    Are your brakes adjusted close to be close to the rims? I see a lot of people that have loose brakes and I wonder how they stop just going 15mph because of how far they have to pull their levers.

    Do you know how to corner? It something worth learning for those curvy descents. And feather your brakes as you go to keep the speed in check, rather than slow down - speed up - slow down - speed up.
    Quote Originally Posted by Scrodzilla View Post
    I'd rather ride a greasy bowling ball than one of those things.
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  9. #9
    Gears? CliftonGK1's Avatar
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    Kool Stop pads can help. The dual-compound or the salmon compound pads wear a little faster but offer better stopping power.
    Have your brakes adjusted for maximum power, which means properly adjusting straddle cables and cantilever angles (if using cantis) or pad clearance and cable travel if using calipers or V-brakes.

    I'm 240 pounds and have a 2.25 mile descent on my morning commute which puts me between 45 and 50mph, and I can bring it to a stop pretty quick if I need to.

    Also, for quick descending stops you need to practice shifting your weight over the back of the bike and using the front brake more than the back.
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  10. #10
    Senior Member Homeyba's Avatar
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    As Clydes we just have better developed descending muscles than most. Going fast is one thing we excell at! I've topped out at 71.4mph. Lots of fun! On the flip side it's good to be able to stop safely in a reasonable distance. There are several good suggestions above. Assuming you know the proper way to stop as clifton pointed out, I'd but them in this order and add one of my own.

    First, make sure your brakes are adjusted properly. Second, Coolstops. Third, Mavic OP Ceramic wheels. With the ceramic wheels you won't have to worry about overheating your wheels/brakes and they stop just as effectively if it's raining or wet.
    It doesn't get harder, you just go slower.

  11. #11
    Senior Member mkadam68's Avatar
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    Quote Originally Posted by wild animals View Post
    ...What can I do to improve this situation?! Aside from losing weight, obviously?
    Quote Originally Posted by hairnet View Post
    ...And feather your brakes as you go to keep the speed in check, rather than slow down - speed up - slow down - speed up.
    +1

    Make sure you don't start the descent with speed. Go slow from the get-go. It's easier then realizing, "Oh my gosh, I have to slow down" when you're already doing 30+mph.

    Also, take your bike to a shop, ask them how's the wear on the pads. Tell them your concerns. Or post detailed photos for us to give some weak advice

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    Braking

    I had the same problem last week at a big cancer ride. I could't hold the bike back and I had to let it go. I reached 45mph and could have gone over 50 but I tried to keep dragging the brakes. Some people recommended kool pads and 1 person said to check my brake adjustment which was off a bit do to a loaner rim.

  13. #13
    Real Human Being wild animals's Avatar
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    71.4?!?! GOOD LORD! Ahaha! I just couldn't handle that.

    My brakes are adjusted pretty close to the rims, but I couldn't say anything beyond that. Probably have to leave that one to the pros

    How do I "feather" the brakes? I tried cranking on them, and it only brought me down to the top of my comfort level, and then the brakes got really noisy and didn't work that well, so I had to stop and let them have a rest. Then I tried to roll, brake, roll, brake, so things wouldn't heat up so much. But I couldn't keep my speed low enough!

    How does one corner properly? I usually kind of lean away from the corner, hold the inside foot up and outside foot down, but there was gravel on the road in some places, and I didn't want to land on my face, so I wasn't comfortable leaning over at all (especially at 25mph on hairpin curves!).

    Sorry if these questions are dumb or whatever. But I usually ride on flat stuff so this is mostly new to me, and I didn't like it. I want to climb to challenge myself (and not exfoliate myself on the street)!
    Go until you stop, then take a break.

  14. #14
    Senior Member mkadam68's Avatar
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    Quote Originally Posted by wild animals View Post
    How do I "feather" the brakes? I tried cranking on them, and it only brought me down to the top of my comfort level, and then the brakes got really noisy and didn't work that well, so I had to stop and let them have a rest. Then I tried to roll, brake, roll, brake, so things wouldn't heat up so much. But I couldn't keep my speed low enough!
    Lightly apply the brakes, then apply harder, then light. Same as you were doing, but the pads never leave the rim. Just degrees of how hard you brake.

    Quote Originally Posted by wild animals View Post
    How does one corner properly?
    Boy...there's a book right there. Best to find a group/club and ask them. Learn in person. Way too much stuff to cover online. Besides, I don't get paid for this stuff.

    Quote Originally Posted by wild animals View Post
    I usually kind of lean away from the corner, hold the inside foot up and outside foot down,
    This is the beginning. But, you're actually leaning "into" the corner. Away from it (outside of the corner) would put you over the edge.

    Quote Originally Posted by wild animals View Post
    but there was gravel on the road in some places, and I didn't want to land on my face, so I wasn't comfortable leaning over at all (especially at 25mph on hairpin curves!).
    Good reaction. Easier said than done: basically, you move your body off the bike so it's directly over the ground and the bike is upright. Then turn the front wheel into the corner. This is one of those rare moments where we actually turn the front wheel instead of just leaning into the turn. Although the bike's still leaning over significantly, here's an extreme example:



    Quote Originally Posted by wild animals View Post
    Sorry if these questions are dumb or whatever. But I usually ride on flat stuff so this is mostly new to me, and I didn't like it. I want to climb to challenge myself (and not exfoliate myself on the street)!
    Good one.

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  15. #15
    Senior Member CollectiveInk's Avatar
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    When you take your bike to the shop, ask to watch while they adjust your brakes and/or cables. It's a VERY important skill to know - and not just "leave it to the pros". (And it's not hard to do.)

    I'm running reds on the front and blacks on the back. But I also upgraded my brakes from the tektro's that came on the Allez, to Bontrager Speed lights (got a killer deal - one I couldn't pass up) and that made a huge difference. Something about less flex, stronger clamping power. Now I can haul my 250# butt from 48mph to 0 seriously quick.

    As for feathering, one technique I use, and taught my son on long descents (especially curvy ones) is to alternate front and rear brake. That way you're always braking, but they have time to cool off.

    The leaning, cornering at speed uses more counter steering than physically steering. Just practice slowly, then working up to higher speeds. It takes time, practice and faith (in your tires, rims, brakes, skill level, etc.)

    But I second "find a local group to ride with and ask/watch them".

    Just keep trying.
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  16. #16
    Senior Member Homeyba's Avatar
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    The biggest thing you can do is look where you want to go! Ignore the dirt (as hard as that sounds). The bike will go where you are looking. So, if you have a path through or around the gravel patches that is where you should be looking. If you fixate on the gravel in the road you will ride right through it. Leaning away from the corner is not good you want to lean into the corner if you are not neutral on the bike. Your foot position is fine. Finally, get your braking done before you enter a corner (you're not racing). As Mkadam68 mentioned, you could (and people have) written books on the subject of cornering.

    btw 71.4 wasn't so bad. I didn't even know I went that fast (because it was dark) until my support vehicle pulled up next to me later on and asked if I knew how fast I was going. I didn't believe them until I looked at the max speed on my own speedo. The key to speed is to only go as fast as you are comfortable. If you start getting uncomfortable you are going too fast and should slow down and get back in your comfort zone. Getting out of your confort zone is a recipe for disaster.
    It doesn't get harder, you just go slower.

  17. #17
    The Site Administrator: Currently at home recovering from a couple of strokes,please contact my assistnt admins for forum issues Tom Stormcrowe's Avatar
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    By the way, as you get more confident, you'll start dropping hills faster. eventually, you'll hit a "Death Wobble". It's a torsional vibration from harmonic frequency differences between the balancing of the front and rear wheel. It's scary as hell, but easy to fix. Just tuck a knee into the top tube and don't stiffen or tighten the upper body. It'll stabilize. My Allez has a death wobble right around 45-48 MPH, and then it stabilizes.
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  18. #18
    foolishly delirious RatedZeroHero's Avatar
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    and learn how to brake with the front as previously mentioned...
    75% of your stopping power is up there!
    but you have to learn how to use it or "endo time" it might be!
    .
    on my Harley I replace front pads more often than rear...

  19. #19
    Mad bike riding scientist cyccommute's Avatar
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    Quote Originally Posted by hairnet View Post
    Are your brakes adjusted close to be close to the rims? I see a lot of people that have loose brakes and I wonder how they stop just going 15mph because of how far they have to pull their levers.
    This is wild animals' main problem...and the problem many people have with brakes! Disc work so well because the travel from full off to full on is a matter of millimeters. Rim brakes can't be set that close but they can be set much closer than his are. My brakes engage within the first 1/8 of travel and a fully locked before half travel.

    Quote Originally Posted by hairnet View Post
    Do you know how to corner? It something worth learning for those curvy descents. And feather your brakes as you go to keep the speed in check, rather than slow down - speed up - slow down - speed up.
    Sorry but this is the wrong way to go. Constant feathering of the brakes, or even riding them, doesn't lead to better control. Constant friction will only lead to overheated wheels. Brake hard before the corners and ease off in the corner. Control speed by braking hard when needed but don't drag the brakes all the time.
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  20. #20
    Mad bike riding scientist cyccommute's Avatar
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    Quote Originally Posted by CliftonGK1 View Post
    Also, for quick descending stops you need to practice shifting your weight over the back of the bike and using the front brake more than the back.
    Shifting your weight back is important but it's not so that you use the front brake more than the back. Most of your stopping power comes from the front to begin with. Moving your weight rearward and down makes the small amount that the rear wheel contributes more effective. The added benefit is that it's harder to pivot around the front hub, i.e. endo, with a lower center of gravity.

    Shifting weight to the rear also keeps the rear wheel from sliding. A rotating tire will stop you faster than a sliding one.


    Quote Originally Posted by RatedZeroHero View Post
    and learn how to brake with the front as previously mentioned...
    75% of your stopping power is up there!
    but you have to learn how to use it or "endo time" it might be!
    Actually about 90% of the stopping power comes from the front brake. There are some people arguing that you should only use your front brake because of this. However, what they are failing to realize is that the maximum deceleration of about 0.5g using front brake only can only be attained by lifting the rear wheel off the ground. Until rear wheel lift occurs, the rear wheel and brake contributes to the over all deceleration of the bicycle.
    Last edited by cyccommute; 08-17-09 at 07:35 AM.
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  21. #21
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    How fast could you safely negotiate the turns on this decent? I have found that terminal velocity for most bikes in most situations is somewhere 45-50 mphs.

    Let me clear up a common misconception. Being a clyde does not make you descend faster than the stick people!! On a descent, there is one and only one force that acts on all of us that is responsible for picking up speed: gravity. The acceleration of gravity is constant regardless of your mass (weight). If you remember back to 6th grade science class, this is why a bowling ball and a ping pong ball would fall at the same speed dropped from a building (ignoring air resistance).

    But speaking of wind resistance, this is the major force that acts on us when riding. There is also wheel friction, but on a fast descent, this becomes negligible in the face of wind resistance. Unlike gravity, the wind's force is different for all of us. The force of the wind resistance acting on us depends on our aerodynamic shape. The bigger the shape, the larger the surface area for the wind resistance to act on. So us clydes have bigger "billboard" for the wind to act on. And though it doesn't make much difference, the heavier clyde rider will have more rolling resistance (friction) from tire contact with the ground.

    Terminal velocity is the point at which the force acting to speed you up (gravity) and the force acting to slow you down (wind resistance) are equal to each other. This is possible because wind resistance increased exponentially with your speed. This means that if your speed doubles, the force of the wind acting against you quadruples. At some point, the resistance forces acting on you equal the force of gravity trying to pull you faster. My personal experience with terminal velocity on my bike is as mentioned above, about 46 mph. No matter how steep the descent, I can't seem to break 46 mph. I actually have a stick buddy who has never broken the 50 mph mark either, so I doubt you will find that you are able to go much faster than this no matter the descent.

    So anyway, my whole point is that if you can safely learn to descend at or near your terminal velocity, you can work with nature instead of against it, save a lot of break pads, and have a lot more fun. But, many would argue that 45-50 mph is never safe on a bike, no matter your skills or the road.
    Last edited by RiverHills; 08-16-09 at 06:24 PM.

  22. #22
    Real Human Being wild animals's Avatar
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    But, aren't we harder to stop, because we're bigger? That's the part I was worried about. I wish I'd taken pictures of the down part of the ride, so you could see what I was dealing with. I only got a couple of the trip up, and they don't do it justice anyway.


    Thanks for all the advice, everybody! I always use both brakes, and on this hill I used them as hard as I could, but I will try moving my weight around on the bike and see what happens (down hills and around corners).

    Hopefully sometime soon I can get my bike in the shop to get the pads changed, brakes adjusted (with me watching).

    Also, I am a lady

    Thanks again!
    Go until you stop, then take a break.

  23. #23
    Senior Member Homeyba's Avatar
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    Quote Originally Posted by RiverHills View Post
    How fast could you safely negotiate the turns on this decent? I have found that terminal velocity for most bikes in most situations is somewhere 45-50 mphs.
    Terminal velocity???? I regularly exceed those speed in corners...I think I mentioned above that I hit 71.4mph on my single bike (verified by my chase vehicle) during RAAM a couple years ago. I've been over 60mph so many times I don't even try and keep count. A gentleman went over 100mph on his bicycle down the side of a mountain a couple years ago.

    Quote Originally Posted by RiverHills View Post
    Let me clear up a common misconception. Being a clyde does not make you descend faster than the stick people!! On a descent, there is one and only one force that acts on all of us that is responsible for picking up speed: gravity. The acceleration of gravity is constant regardless of your mass (weight). If you remember back to 6th grade science class, this is why a bowling ball and a ping pong ball would fall at the same speed dropped from a building (ignoring air resistance).

    But speaking of wind resistance, this is the major force that acts on us when riding. There is also wheel friction, but on a fast descent, this becomes negligible in the face of wind resistance. Unlike gravity, the wind's force is different for all of us. The force of the wind resistance acting on us depends on our aerodynamic shape. The bigger the shape, the larger the surface area for the wind resistance to act on. So us clydes have bigger "billboard" for the wind to act on. And though it doesn't make much difference, the heavier clyde rider will have more rolling resistance (friction) from tire contact with the ground.
    It's not that simple. We don't live in a vacuum. Since we're in 6th grade, go to your nearest cub scout pine wood derby race and try to win with an un weighted car. I ride with little racer boys and easily smoke them on descents. By your understanding of physics, greater wind resistance, greater rolling resistance etc., they should drop me like a rock on the descents just like they do on the climbs! Man, that'd suck!!!


    Quote Originally Posted by RiverHills View Post
    Terminal velocity is the point at which the force acting to speed you up (gravity) and the force acting to slow you down (wind resistance) are equal to each other. This is possible because wind resistance increased exponentially with your speed. This means that if your speed doubles, the force of the wind acting against you quadruples. At some point, the resistance forces acting on you equal the force of gravity trying to pull you faster. My personal experience with terminal velocity on my bike is as mentioned above, about 46 mph. No matter how steep the descent, I can't seem to break 46 mph. I actually have a stick buddy who has never broken the 50 mph mark either, so I doubt you will find that you are able to go much faster than this no matter the descent.

    So anyway, my whole point is that if you can safely learn to descend at or near your terminal velocity, you can work with nature instead of against it, save a lot of break pads, and have a lot more fun. But, many would argue that 45-50 mph is never safe on a bike, no matter your skills or the road.
    Maybe if you took your hands off the brakes you'd go faster? 46mph? I'm still pedaling at 46mph!
    It doesn't get harder, you just go slower.

  24. #24
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    Quote Originally Posted by Homeyba View Post
    Terminal velocity???? I regularly exceed those speed in corners...I think I mentioned above that I hit 71.4mph on my single bike (verified by my chase vehicle) during RAAM a couple years ago. I've been over 60mph so many times I don't even try and keep count. A gentleman went over 100mph on his bicycle down the side of a mountain a couple years ago.
    Sorry, that's BS. Check your units. 71.4 km/h maybe

    It's not that simple. We don't live in a vacuum. Since we're in 6th grade, go to your nearest cub scout pine wood derby race and try to win with an un weighted car. I ride with little racer boys and easily smoke them on descents. By your understanding of physics, greater wind resistance, greater rolling resistance etc., they should drop me like a rock on the descents just like they do on the climbs! Man, that'd suck!!!
    That has nothing to do with air drag. The heavier cars win because they weigh more and have greater inertia, so they go farther before stopping on the flat part of the track below the ramp.

    Just like the pinewoord car, heavier riders are indeed harder to stop (to answer OP's question). That is why the point of my post was to learn to deal with the speed instead of fighting it.

    Maybe if you took your hands off the brakes you'd go faster? 46mph? I'm still pedaling at 46mph!
    More BS.

  25. #25
    Mad bike riding scientist cyccommute's Avatar
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    Quote Originally Posted by RiverHills View Post
    Sorry, that's BS. Check your units. 71.4 km/h maybe
    I've done more than 50 mph on a single and more than 55 mph on a tandem. I've also know other people who have done much faster on a tandem. Terminal velocity on a bike would be close to terminal velocity in free fall...around 125 mph. The fastest downhill speed is currently 130 mph...on snow

    Quote Originally Posted by RiverHills View Post
    More BS.
    Depends on gearing. With a rear cog of 11 teeth and a front ring of anything above 48 teeth (48, 50, 52, 53), I can be pedaling at over 46 mph. I'm not sure that even I have the guts to go fast enough to spin out a 53/11 gear. At 50 mph that gear is still feeling like it has another 50 or 60 rpm before you'd be spinning too fast.
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