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No brake fixies

Old 08-06-12, 06:02 PM
  #51  
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Originally Posted by Face Palm View Post
What it comes down to is that focusing on brakeless fixie riders as a monumental threat as done by the OP creates a falsely negative exceptionalism for the purpose of riling up the crowd. There are lots of dangerous riders on the road, just as there are lots of good riders (the same goes for drivers). But seeing brakeless fixies as such a threat, to the exclusion of discussion of other, just as common threats, exhibits an almost willful confirmation bias.
First off, if my falsely negative exceptionalism has riled up a crowd of vigilantes I can only plead that you Stay Calm and Carry On. I was unaware of my extraordinary powers.
And willful confirmation bias... wow!!! I didn't go to college so had to look it up and I plead not guilty. I'm not relying on confirmation of the patently obvious: that riding in the street without brakes is hazardous to other road users. And I don't lose sleep about the well-being of my brakeless brothers. That's their business. I don't want to convince them of anything.
I am concerned, though, with getting home safely each day and offended when someone else's fashion sense adds an avoidable risk to my day. I could (and do) complain about riding with headphones, texting while riding, overtaking without warning, superwide pedals on very close and silent electric bikes, illegally parked vehicles, inattentative pedestrians and a pile of other things that I see each day. There's a lot to choose from. Oddly enough, in my little world, aggressive drivers are low on the list.
Bottom line is that I try to do my bit and expect others to do the same including drivers, pedestrians and cyclists.
Apparently my enthusiastic tone offended some of you and that's unfortunate. Nonetheless, brakeless riding is a topic I haven't seen discussed and it deserves an airing.
And it seems to me that the Advocacy & Safety forum is the right place to advocate for better enforcement of laws against an unsafe practice.
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Old 08-06-12, 06:10 PM
  #52  
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one problem is, with a brakeless fixed gear, if you have a problem stopping in time for whatever reason, it's not just YOUR problem. it's a problem for whoever's in front of you, behind you, trying to get out of your way or trying to avoid hitting you or anyone else who's reacting to YOUR situation. so in that sense I think it's kind of a safety hazard and selfish. dangerous for other people besides yourself, which should be a consideration for any rider.
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Old 08-06-12, 08:28 PM
  #53  
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Originally Posted by CB HI View Post
Then I think you and the others pushing the point of view should only be allowed to ride bikes with disk brakes.
Huh? You ignored most of my post and implied I was advocating that something should required. I was not--not at all. Don't be a jerk, please.

(Also, I see nothing wrong with disc brakes. Are you making some kind of joke that I'm not getting?)
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Old 08-06-12, 08:39 PM
  #54  
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I had to ride brakeless freewheel a couple of days last week. I used my emergency brakes - foot on front wheel, jammed behind fork. Even took the time to get used to doing it with my left foot so I'm ambidextrous now.
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Old 08-06-12, 08:41 PM
  #55  
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Originally Posted by LesterOfPuppets View Post
I had to ride brakeless freewheel a couple of days last week. I used my emergency brakes - foot on front wheel, jammed behind fork. Even took the time to get used to doing it with my left foot so I'm ambidextrous now.
Brakeless freewheel? That's hardcore, man. You could start a new trend called "unfixies".
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Old 08-06-12, 11:15 PM
  #56  
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Originally Posted by lostarchitect View Post
Huh? You ignored most of my post and implied I was advocating that something should required. I was not--not at all. Don't be a jerk, please.

(Also, I see nothing wrong with disc brakes. Are you making some kind of joke that I'm not getting?)
Yes you missed the point. You may not be as harsh in your position saying they SHOULD have this or that, as the others who are almost demanding that fixed gear riders who have legs for brakes should/must have hand caliper brakes.

The next step is for someone else to come along and demand that caliper brakes are not good enough, you must have disk brakes. And then someone will demand the next evolution of brakes for all bikes.

There are some LBS that cannot sell high end track bikes that the cyclist only intend on using to race on the track because of nonsense that started out just like this.

When you start projecting that others should ride with the equipment that you feel they should have (similar to stating everyone should ride with a helmet on) rather than stating you would not personally ride without hand brakes.

Stating everyone should ride with a helmet on, gets used to make mandatory helmet laws by the politicians.
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Old 08-06-12, 11:30 PM
  #57  
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Originally Posted by asmac View Post
Oddly enough, in my little world, aggressive drivers are low on the list.
Oddly, your list seems messed up:

http://news.nationalpost.com/2011/11...lled-by-truck/

Feel free to link to the death that a Toronto fixed gear without hand brakes caused.

Bet you run out of links before I do.
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Old 08-07-12, 12:06 AM
  #58  
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Originally Posted by Face Palm View Post
Brakeless freewheel? That's hardcore, man. You could start a new trend called "unfixies".
Brakeless with freewheel has been almost standard in BMX freestyle, since the mid 90s. I never saw the attraction.
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Old 08-07-12, 01:20 AM
  #59  
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Riding 'brakeless' is mostly about fashion.

However, it is not necessarily more dangerous than riding a bike with brakes, for the operator or other road users. Just ride within the limits of bike and rider, whatever they are. You can (easily) ride outside the limits on a freewheel bike, or a fixed wheel bike. Brakeless riders are not necessarily "endagering" you. Brakeless bikes are not the seventh sign of the Apocalypse. It sounds a LOT more exciting than it really is.

I rode a no brakes fixie for several years as a young messenger in the mid-90s. Like most of my compatriots, I did it because I was bored, wanted more challenge and enjoyed that it freaked everybody out. (Funny that it still does -- that's lucky for the young hipsters of today.) Later, as an old messenger, I rode no brakes again for a while... I was in the middle of building a singlespeed and decided to just throw on a fixed wheel for a few days until I got the brakes installed, because I needed a bike to ride. I never got the brakes. There really wasn't a pressing need for them. But I did get bored -- disgusted -- with the fixed wheel rather quickly and started riding a different bike.

All in all I probably rode 30-50,000 miles in heavy traffic without brakes. I can't recall a single close call or crash in that time. Not one. Any crash I've experienced occurred when I was riding a freewheel bike with hand brakes. I don't think that record is down to luck either. My experience is not unusual. Riding a fixed wheel without brakes has a way of slowing you down and putting your head in the game. Some of the most conservative and conscientious riders I have ever known rode no-brakes exclusively.

Personally, I grew to really dislike fixed gears. I doubt I will ever ride one again. I do miss the one (imo) advantage of riding fixed -- being intimately connected to the machine, such that subtle changes in speed can be affected instantaneously -- but the advantage is outweighed by numerous disadvantages.

If you're going to limit your riding so much by using a fixed wheel, you may as well go no-brakes and catch some fashion points. Throwing a brake or two on a fixed gear bike won't solve the fixed wheel stopping problem, by the way, it just helps a bit. You're still going to flip if you try a freewheel-style panic stop on a fixed wheel with brakes.

If you really want to tear up the road and terrorize the populace, go with a freewheel and brakes.
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Old 08-07-12, 04:48 AM
  #60  
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Stick to the topic

Originally Posted by CB HI View Post
Oddly, your list seems messed up:

http://news.nationalpost.com/2011/11...lled-by-truck/

Feel free to link to the death that a Toronto fixed gear without hand brakes caused.

Bet you run out of links before I do.
Your link refers to a very sad and tragic case of a cyclist (with a trailer) who made the mistake of squeezing in on the right of a large right-turning truck. What it has to do with this conversation I'm not sure.

I could point to a recent Ontario coroner's report that mandatory helmets would save lives. Is that the kind of evidence you pay attention to? Not that I want to discuss helmets but just wondering what it takes to persuade you of the obvious.
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Old 08-07-12, 09:34 AM
  #61  
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Originally Posted by CB HI View Post
When you start projecting that others should ride with the equipment that you feel they should have (similar to stating everyone should ride with a helmet on) rather than stating you would not personally ride without hand brakes.

Stating everyone should ride with a helmet on, gets used to make mandatory helmet laws by the politicians.
Slippery slope arguments are BS. Sorry. I get to have opinions just like you do.
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Old 08-07-12, 03:33 PM
  #62  
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Originally Posted by CB HI View Post
The next step is for someone else to come along and demand that caliper brakes are not good enough, you must have disk brakes. And then someone will demand the next evolution of brakes for all bikes.
As said, that's a nice slippery slope, but the point is that it's not even a slope -- it's a cliff.

A skilled brakeless fixie rider can probably pull around 0.1 Gs by locking their back tire for a bit, then unlocking before they lose control, locking, etc.

Grandma on her cruiser can probably pull about 0.2 Gs with her coaster brake by doing it just the right amount. Same goes for somebody with a caliper brake just on the back tire.

I'm not sure how effective "jamming your foot between your front wheel and frame is", but it probably belongs in here somewhere.

Somebody with a properly adjusted front caliper or disc brake can pull about 0.6 Gs before the bike endos. More skill with the brake means that somebody can get closer to the limit without flipping, but it doesn't take much skill to get pretty close.

For completeness, cars don't have problems with endo-ing, so the limiting factor is usually the traction of their tires -- so they can brake at 0.8 Gs to 1.1 Gs or so under ideal conditions.

Disc brakes won't stop you faster than caliper brakes. They will handle some extreme cases somewhat better, however -- descending on a mountain, wet rims.

Having a rear brake in addition to the front brake makes a nice backup, but it won't really help you stop much faster. It will help a little, however, especially if you're not so skilled in the use of your brakes.

But that single front brake will stop you about 3x as quickly as a single rear brake, and possibly 6x (this is just a rough guess) as fast as a brakeless fixie rider can stop (unless he jams his foot between his front wheel and frame or fork, of course.)

If he can keep his speed down enough and stay out of situations where might need to stop quickly, then this will probably work out fine. If he doesn't, then there may be trouble. Same goes for grandma on her cruiser, but her improved braking gives her added flexibility, and cruisers (or other bikes with only a rear coaster brake) aren't usually designed for speed anyways.
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Old 08-07-12, 03:38 PM
  #63  
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Fixies are so last decade. Track bikes are great for the track but on the street, you are riding a bike thats in the wrong gear 90% of the time and that you have to ride like a little old lady because the brakes suck.
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Old 08-07-12, 04:25 PM
  #64  
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Originally Posted by dougmc View Post
As said, that's a nice slippery slope, but the point is that it's not even a slope -- it's a cliff.

A skilled brakeless fixie rider can probably pull around 0.1 Gs by locking their back tire for a bit, then unlocking before they lose control, locking, etc.

Grandma on her cruiser can probably pull about 0.2 Gs with her coaster brake by doing it just the right amount. Same goes for somebody with a caliper brake just on the back tire.

I'm not sure how effective "jamming your foot between your front wheel and frame is", but it probably belongs in here somewhere.

Somebody with a properly adjusted front caliper or disc brake can pull about 0.6 Gs before the bike endos. More skill with the brake means that somebody can get closer to the limit without flipping, but it doesn't take much skill to get pretty close.

For completeness, cars don't have problems with endo-ing, so the limiting factor is usually the traction of their tires -- so they can brake at 0.8 Gs to 1.1 Gs or so under ideal conditions.
...
You may have missed the memo that the old formulae for max braking on a bicycle were proven to be bunk. Max deceleration on a freewheel bike with good handbrakes and skilled rider is .8-.9 g. Max braking for a fixed with no brakes and a really skilled rider is probably about .5. You are correct about max braking for cars with good performance.

I think I may be one of the few people in the world who has actually tested max braking on a bike with actual physical experiments with multiple riders. The experiment is not easy to control but it can be controlled well enough to see that .6 g is nowehre near max braking. .6-g is a very mellow stop indeed, perhaps near the max deceleration for a seated, static rider. Seated, static riders are doing it wrong, to put it mildly. Skill level has a huge effect on max g-force.
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Old 08-07-12, 04:28 PM
  #65  
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Originally Posted by San Rensho View Post
Fixies are so last decade. Track bikes are great for the track but on the street, you are riding a bike thats in the wrong gear 90% of the time and that you have to ride like a little old lady because the brakes suck.
That pretty much sums it up.
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Old 08-07-12, 04:34 PM
  #66  
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Originally Posted by RobertHurst View Post
Seated, static riders are doing it wrong, to put it mildly. Skill level has a huge effect on max g-force.
What qualifies as doing it right?
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Old 08-07-12, 04:58 PM
  #67  
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Originally Posted by RobertHurst View Post
You may have missed the memo that the old formulae for max braking on a bicycle were proven to be bunk.
Apparently I did. Could you please send me a copy of that memo or a link to it?

The books I've got say about 0.6 Gs for a front brake and 0.2 Gs for a rear brake. But as you said, they're pretty old. I wouldn't expect this to change much -- the physics was well understood decades ago and it's easy enough to measure in the real world even decades ago, but certainly -- the math did involve a static rider, and I think he was seated too.

Max braking for a fixed with no brakes and a really skilled rider is probably about .5.
I'd love to see how the memo says this happens ...

.6-g is a very mellow stop indeed, perhaps near the max deceleration for a seated, static rider. Seated, static riders are doing it wrong, to put it mildly. Skill level has a huge effect on max g-force.
You may be right about the seated, static part. I wouldn't call it so incredibly mellow (as the rider is very close to an endo if he's doing it right), but by throwing your center of gravity back and down you probably could improve on it somewhat. But up to 0.9 Gs? I'd like to see that memo. (I assume we're talking about standard, upright bikes, right? Not tandems or recumbents?)

Hopefully it includes video or pictures of people doing these stops -- I'd like to see what these riders are doing to improve their stopping distances. Sliding your butt back and down (all the way onto the back wheel if you can manage it) would seem to be a given, but there must be more than that ...

Edit: http://www.industrializedcyclist.com...-pitchover.pdf gives a good analysis of the butt in the saddle and the butt behind the saddle, and the latter comes close to your assertion. It's still "static", however -- do you have something "non-static" that improves on this? And this doesn't cover a rear brake only situation, but maybe I can work that out.

Hmm. Forrester gives a rear-brake only value of 0.27 Gs on some specific geometry here in the "9.17 Front Brake Usage" section, though I imagine that doesn't include moving one's butt. (Can a fixie rider still lock the rear wheels effectively when their butt is way behind the saddle rather than in it or over it? I've never tried.) In any event, since a fixie rider has a hard time slowing the rear tire -- instead locking it for periods of time -- I doubt they'd be able to even meet this figure.

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Old 08-07-12, 07:46 PM
  #68  
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Originally Posted by asmac View Post
Your link refers to a very sad and tragic case of a cyclist (with a trailer) who made the mistake of squeezing in on the right of a large right-turning truck. What it has to do with this conversation I'm not sure.
The woman was riding uphill, yet she somehow caught up to the truck before it could make it's turn and squeezed in. BS The truck either passed her just before the stop or after the cyclist had just made her stop. Likely the truck was looking left while ignoring the cyclist, trying to make a rolling (CA) style stop. Not surprised you are a BLAME the cyclist FIRST type of guy.

Originally Posted by asmac View Post
I could point to a recent Ontario coroner's report that mandatory helmets would save lives. Is that the kind of evidence you pay attention to? Not that I want to discuss helmets but just wondering what it takes to persuade you of the obvious.
Yes, I figured you for a guy who would believe the helmet myths and bad/misleading data in the Ontario coroner's report .
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Old 08-07-12, 07:47 PM
  #69  
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PS - still waiting for your - "fixed gear without handbreaks kills" link.
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Old 08-07-12, 08:25 PM
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Originally Posted by CB HI View Post
PS - still waiting for your - "fixed gear without handbreaks kills" link.
It's spelled "brake."

Keep waiting; you don't really have much of a point and I'll let you do your own research. Being able to stop is an important thing and someone without brakes (regardless of their self-proclaimed expert status) can't do that nearly as effectively as someone with brakes. That creates an unnecessary hazard for others. Sorry you can't understand that. Continue badgering if you wish...
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Old 08-07-12, 08:45 PM
  #71  
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Originally Posted by asmac View Post
It's spelled "brake."

Keep waiting; you don't really have much of a point and I'll let you do your own research. Being able to stop is an important thing and someone without brakes (regardless of their self-proclaimed expert status) can't do that nearly as effectively as someone with brakes. That creates an unnecessary hazard for others. Sorry you can't understand that. Continue badgering if you wish...
For chrissakes. Has none of the preceding discussion made any impact upon your decision to complain without seriously supporting your argument or being open to discussion? You speak in such absolutes, yet can't be bothered to point to a single study to back yourself up?

But thank you for freeing us from the burden of tiresome proof. You have freed me to declare that anyone with handlebars in which the drop section is lower than saddle height "regardless of their self-proclaimed expert status" can't safely stop in time or see the road as effectively as someone with an upright riding position because of the portion of a second longer it takes them to raise their necks to see forward. I swear this is true, and I'm "sorry you can't understand that." But don't think I'm going to provide you with anything more than anecdotal rantings to support my argument. Find your own damn studies. Everyone riding with handlebars less than four inches above saddle height is a menace on the road.
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Old 08-07-12, 08:46 PM
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Originally Posted by CB HI View Post
The woman was riding uphill, yet she somehow caught up to the truck before it could make it's turn and squeezed in. BS The truck either passed her just before the stop or after the cyclist had just made her stop. Likely the truck was looking left while ignoring the cyclist, trying to make a rolling (CA) style stop. Not surprised you are a BLAME the cyclist FIRST type of guy.

Yes, I figured you for a guy who would believe the helmet myths and bad/misleading data in the Ontario coroner's report .
The police report said otherwise. The truck was there first. She was in a hurry. It was a tragic misjudgement and very sad.
I don't think I expressed an opinion about mandatory helmets but was just wondering what evidence you would consider reliable. None, apparently, if it contradicts what you want things to be.
Anyhow, this is getting boring. No more from me.
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Old 08-07-12, 08:55 PM
  #73  
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Originally Posted by asmac View Post
The police report said otherwise. The truck was there first. She was in a hurry. It was a tragic misjudgement and very sad.
I don't think I expressed an opinion about mandatory helmets but was just wondering what evidence you would consider reliable. None, apparently, if it contradicts what you want things to be.
Anyhow, this is getting boring. No more from me.
Yes, because police reports ALWAYS reflect the true course of events. No chance of that ever being a mistaken assumption, or that the police would show anti-cyclist prejudice...
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Old 08-07-12, 09:12 PM
  #74  
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Originally Posted by dougmc View Post
Apparently I did. Could you please send me a copy of that memo or a link to it?
You already linked to it! (http://www.industrializedcyclist.com...-pitchover.pdf) That's my website, and the formula by Joe Riel in the link was worked up in direct response to the physical experiments I performed with several riders. You are correct, Joe's math still assumes a static rider with weight back, and he still comes up with .8-plus g's for a max deceleration, which is already 30% more g's than the original formula which put the rider on the seat.

Formula or not, it is obvious that the movement of the body mass, not simply the position, has a great deal to do with stopping distance. Consider the bike-rider system -- the rider makes up the vast majority of the weight of the system (85% would be typical for a road bike-and-rider). So moving that weight will have a major effect on the whole system. Imagine a beach ball with a heavy weight inside of it. If you could somehow control that weight, move it within the envelope of the ball, you could make the ball act rather unlike a ball is expected to act. The bike-rider system is analogous. Riders can heave their bikes up onto rocks and things using movement of the body weight alone; exaggerated, timed movement of body weight can also help slow the bike. (And keep the back end of the bike under some control during a max stop.)

Joe said he would work on a formula including the body movement as well as position, but I don't think he ever did. It would be an extremely complex formula, partly because the timing of the movement is critical. So you've got lots of different things going on at the same time which are difficult to discern and put into numbers. But -- one thing is obvious and that is the old formula was waaaay off, because it ignored the effect of body position and movement. Their formula simply does not describe what happens in reality.

I say .8 - .9g based on my experiments, not math. In dozens of attempts I don't think anyone went clearly over .9g, but it's very possible that the theoretical max deceleration would be higher than that.


Originally Posted by dougmc View Post
I'd love to see how the memo says this happens ...
How does a skier stop without brakes, or a hockey player? 'Brakeless,' yet they can stop fairly quickly. Good fixed riders can do basically the same thing by throwing the back wheel sideways. It's not easy, or the preferred way to stop a bike by any means. If you're panic stopping on a fixed wheel, that's bad news.

Originally Posted by dougmc View Post
You may be right about the seated, static part. I wouldn't call it so incredibly mellow (as the rider is very close to an endo if he's doing it right), but by throwing your center of gravity back and down you probably could improve on it somewhat. But up to 0.9 Gs? I'd like to see that memo. (I assume we're talking about standard, upright bikes, right? Not tandems or recumbents?)

Hopefully it includes video or pictures of people doing these stops -- I'd like to see what these riders are doing to improve their stopping distances. Sliding your butt back and down (all the way onto the back wheel if you can manage it) would seem to be a given, but there must be more than that ...
Really, it's not that a .8-g or .9g stop is incredibly amazing or video-worthy, it's that a .6-g stop is absolutely pedestrian. Think old lady on a Landrider. The formula was bogus, that's all. If people can't do a .7 g stop then something is seriously wrong with the way they are handling the bike, or with the brakes themselves. It's not a big deal to do a .7-g stop. .9g just isn't as amazing as people have asserted and assumed. I guess I was just the first and only person to check the formula against actual physical experiments.


Originally Posted by dougmc View Post
Hmm. Forrester gives a rear-brake only value of 0.27 Gs on some specific geometry here in the "9.17 Front Brake Usage" section, though I imagine that doesn't include moving one's butt. (Can a fixie rider still lock the rear wheels effectively when their butt is way behind the saddle rather than in it or over it? I've never tried.) In any event, since a fixie rider has a hard time slowing the rear tire -- instead locking it for periods of time -- I doubt they'd be able to even meet this figure.
When people trust Forester's grand proclamations, they are going to be wrong about all kinds of things.
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Old 08-07-12, 09:27 PM
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Originally Posted by asmac View Post
What qualifies as doing it right?
Don't be seated, or static. Separate from the machine. Be loose and relaxed. Well-timed, exaggerated body movement. Use both brakes -- although the front will do the vast majority of the work, using both allows for considerably lower stopping distance. Don't listen to those (like Forester again) who tell you to avoid a rear wheel skid -- that's ridiculous. In a near-max stop, the rear wheel will skid or come off the ground. If this causes a loss of control it proves you weren't loose enough. I recommend people practice panic stops.
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