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  #16  
Old 06-20-2017, 12:09 AM
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Ti Designs Ti Designs is offline
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Originally Posted by fuzzalow View Post
This is a statement about acquiring skills not an ad hominem.
http://psych.colorado.edu/~vanboven/...er_dunning.pdf

When David Dunning and Justin Kruger wrote "Unskilled and unaware of it", they used an example they knew nobody would identify with. This allowed them to define a behavior without insulting the reader. For this they won a nobel prize. If you look at figure 1 and take note that it doesn't exclude the reader, you may come to the realization that for any given skill there is a 75% chance that you are less competent than you think. The truth has this way of pissing people off...

I've been working on a paper about why people have abandoned the scientific process (hypothesis, testing, conclusion) in favor of their perceptions - the very basis for the Dunning-Kruger effect. I stumbled upon a case I found rather amusing.

At Harvard, if you do the average amount of work in a class you'll probably get a B+. Do a little more work and you'll get an A, less and you'll get a B-. If you do nothing you might get a C. If you take the grades of an entire class and plot the distribution over a standard grading scale (F = 0 - 59, D = 60 - 69, C = 70 - 79, B = 80 - 89, A = 90 - 100) you get a something which is very skewed to the right.

If you take Dunning/Kruger's figure 1 graph and use it as a math function (it's a one to one mapping of perceived skill to tested skill) applied to a standard distribution, you get the exact same curve.

If they let the students at the lowest skill levels think they are near the top, their parents will continue to donate money to the school...



I know that none of this relates to anyone here, because we all had to pass the testing procedures on all things cycling before being granted membership.
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  #17  
Old 06-20-2017, 12:30 PM
benb benb is offline
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You still have to be able to reach the bars to operate the controls. It doesn't matter if you aren't supporting your weight on the bars.

If the bars are too far away for you to comfortably operate the controls/reach the bars you're not doing yourself any favors. Probably hurting your hands/arms/shoulders/back in the process.

Tons of room to just put another drop bar on with less reach...
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  #18  
Old 06-21-2017, 07:58 AM
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Ti Designs Ti Designs is offline
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Originally Posted by benb View Post
You still have to be able to reach the bars to operate the controls. It doesn't matter if you aren't supporting your weight on the bars.
These discussions keep popping up because people think their position is determined by where their bars are. If that's the case, there will always be weight on the bars and you'll never be as comfortable as you are standing or sitting. Body position should be determined by the saddle-pedal relationship. Your weight either goes on the saddle or on your pedals. When you stand or sit, do you find yourself bracing against walls or tables with your hands? This is a question of which order you do things, and there's only one order that works. First get the body weight on the pedals - forget about where the bars are at that stage. Once that works, put the bars where the hands find their way out to the hoods when the body weight is over the pedal at 3:00.

At least a few times a week I have people show up at my fitting station asking me to just check their stem length. Then they sit on the bike and put 1/3rd of their upper body weight on the handlebars. These are not people who walk down the street on their hands... The problem here is one of opportunity, coupled with the fact that your eyes are mounted in the front of your head. Look, there are handlebars right in front of me, I can put my weight there! I have a friend who teaches rock climbing. When you rappel, the speed control is below you, but the newbies always try to grab the rope above them - 'cause it's what they see...

At some point I'm going to start marketing the rubber fitting stem - it puts the bars where they should be based on angle and length, but you can't put your weight on them...


Lastly, let's talk about the drops, 'cause people so want to use them... There's this concept called "within range of motion" that I keep babbling about. It's where you can pedal the bike without your hips getting pushed up off the saddle. Each joint in your body has it's own limits to range of motion. My hips get about 115 degrees on a good day. Now think of the hip angle on the bike as the shoulder to hip to knee. The lower my back, the more angle I need from my hip. If I exceed my limit (by trying to fold myself in half), the crank isn't gonna bend, my leg isn't going to break, my hip is going to get pushed out of the saddle. That's called outside of your range of motion - don't do it. The drops have a very specific purpose, I call it the scary handling position because it's where you need to be to get your center of gravity low and centered between the wheels. If that happens to be outside of your range of motion, it's not where you're going to spend much time.
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  #19  
Old 06-21-2017, 03:01 PM
Clean39T Clean39T is online now
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Quote:
Originally Posted by Ti Designs View Post
These discussions keep popping up because people think their position is determined by where their bars are. If that's the case, there will always be weight on the bars and you'll never be as comfortable as you are standing or sitting. Body position should be determined by the saddle-pedal relationship. Your weight either goes on the saddle or on your pedals. When you stand or sit, do you find yourself bracing against walls or tables with your hands? This is a question of which order you do things, and there's only one order that works. First get the body weight on the pedals - forget about where the bars are at that stage. Once that works, put the bars where the hands find their way out to the hoods when the body weight is over the pedal at 3:00.

At least a few times a week I have people show up at my fitting station asking me to just check their stem length. Then they sit on the bike and put 1/3rd of their upper body weight on the handlebars. These are not people who walk down the street on their hands... The problem here is one of opportunity, coupled with the fact that your eyes are mounted in the front of your head. Look, there are handlebars right in front of me, I can put my weight there! I have a friend who teaches rock climbing. When you rappel, the speed control is below you, but the newbies always try to grab the rope above them - 'cause it's what they see...

At some point I'm going to start marketing the rubber fitting stem - it puts the bars where they should be based on angle and length, but you can't put your weight on them...


Lastly, let's talk about the drops, 'cause people so want to use them... There's this concept called "within range of motion" that I keep babbling about. It's where you can pedal the bike without your hips getting pushed up off the saddle. Each joint in your body has it's own limits to range of motion. My hips get about 115 degrees on a good day. Now think of the hip angle on the bike as the shoulder to hip to knee. The lower my back, the more angle I need from my hip. If I exceed my limit (by trying to fold myself in half), the crank isn't gonna bend, my leg isn't going to break, my hip is going to get pushed out of the saddle. That's called outside of your range of motion - don't do it. The drops have a very specific purpose, I call it the scary handling position because it's where you need to be to get your center of gravity low and centered between the wheels. If that happens to be outside of your range of motion, it's not where you're going to spend much time.
I appreciate all the thought you put in here...I just wish you weren't on the opposite side of the country! I feel like I've been trying to shoehorn myself onto bikes I've lusted after instead of figuring out what's right for my unique height/measurement proportions. I've done a professional fit with someone I think did a good job of working with my proportions, but they were still fitting me to a bike I came in with (CAAD10 60cm), not starting from a more open place.

Since this is a thread about reach, heres a YouTube clip of me on my recently acquired Holland where I'm trying to figure out if my reach and positioning overall is decent: https://www.youtube.com/watch?v=TPLgEHClqpc I've since raised my saddle a bit. The reach feels mostly okay, but only because of the 0-setback post, which may not be right for me. When I was fit, she wanted around 12cm of setback from the BB to saddle nose, and this is only 8-9cm. I'm starting to think that I have somewhat short torso/arms relative to my height and maybe need to be on a shorter TT bike with a longer ST and HT. I generally like the front-end handling of a bike with a 120mm stem. Maybe I need to be on more of a 57.5-58.5TT to get both the setback I need and the stem length. I can't see putting a 90mm stem on the Holland and being happy with how it handles. And it seems like to get the saddle drop that's comfortable, but not too upright, somewhere around 8cm, I need at least a 19.5cm HT (non-integrated).

Color me confused.
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  #20  
Old 06-29-2017, 08:59 AM
8352 8352 is offline
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Ended up getting an 80mm stem rather than a 100mm. Thought it was going to be a bit higher, but not really. The bars I got perhaps have a bit less of a reach too. Feels more comfortable for now as I can actually reach my brake hoods without my arms locked out! Again, I have my levers at the furthest point, which doesn't help. But the thing is, when I bring the levers closer to the stem, there is an uncomfortable curve made from the awkward brake lever hoods. Perhaps I know what my next upgrade will be!


Last edited by 8352; 06-29-2017 at 09:13 AM.
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  #21  
Old 06-30-2017, 04:46 PM
yinzerniner yinzerniner is offline
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How does your torso feel with the new stem and bars? It appears to me the axis intersection is actually lower than the original combo, so that might help in naturally extending your reach.
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  #22  
Old 07-01-2017, 07:54 AM
numbskull numbskull is offline
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I'm no expert (and don't want to sound presumptive) but I've gone through something similar and here is what helped me a lot.

First I'd rotate the original bars and reposition the levers. Ends pointing at the rear caliber (or even some above with that stem height) would be traditional. Yours are aiming for your sprocket. Doing so will shorten the reach to the drops and allow you to slide the levers closer in without creating too steep an angle on the hoods.

Next I'd flatten the seat. A forward tilt made me slide forward and unconsciously raise my back (which shortens reach) and use my arms to counteract it. Probably you (like I) have some perineal pressure issues that make you want to tilt the seat but at least in my case flattening the seat and raising it helped resolve this.

Last, and this seems counter-intuative but is worth trying anyways, raise the seat a bit (and possibly also reconsider crank length). This made a BIG difference for me. If you are not already pedaling somewhat toe down then bringing up your seat opens your hip angle when the pedal is at top center and allows you to flatten and lower your back greatly extending your reach. You likely will find you need to slide your seat back a bit to rebalance over your COG but even then the net gain in reach can be significant.
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  #23  
Old 07-05-2017, 04:52 PM
Ken Robb Ken Robb is offline
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I have to have my Brooks just slightly nose-up so that I have no tendency to slide forward and thereby put pressure on my hands. Your saddle doesn't look nose-up to me. I use a bubble level and one bubble up from level seems to be about right on all of my bikes.

I like Nitto Noodle bars even with or above my saddles.
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  #24  
Old 07-07-2017, 09:54 PM
Pastashop Pastashop is offline
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+1 on the recommendations to tilt the saddle a bit and slide it back. The way the Brooks suspension saddle - when level - seems to deform when I sit on it makes me slide toward the bars, with more weight on the bars and somehow less comfort for the back. So, I now tilt it back. Note that the way a B17 is shaped, most people find they prefer the bars level with the saddle. If you lace in the skirts of the saddle, it can help a bit reshape it for more sitting comfort in a more "aero" position. But again, a more "aero" position will generally require more saddle setback for balance.

Oh, also... One thing that seems to be a tacit assumption that many cyclers make about saddle height is that it should allow for a nearly full extension of the leg at the bottom or ~5 o'clock position. I don't think it's a good set point necessarily, particularly for people who spend a lot of time seated at their desk and may have lost some flexibility. If you grok what TiDesigns is talking about in his videos on fit, and experiment with your own flexibility / range of motion, you'll see. Sometimes having more of a bend in the knee can free up your glutes to do more work with less strain on the lower back and core.

Also also, doing planks properly and frequently can alleviate a lot of lower back pain. Weird but seems to work for me.
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