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  #1  
Old 12-23-2016, 09:25 PM
stephenmarklay stephenmarklay is offline
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Tis the season for making changes

Since its winter I decided to hone in my position a little.

I changed my position some time ago but after paying better attention in class (ok Ti Designs videos) I raised my saddle about a 1.0cm and also moved my seat forward.

Since I am going to be working on my pedal stroke mostly for the next couple of months this was a good time to make changes.

EDIT: On a side note I had my daughter video tape me on my bike and I realized that my stem is way too short and tall. I had been using a taller quill to ease my body back into cycling this year but now with my seat more forward I am sitting way too upright.

Last edited by stephenmarklay; 12-29-2016 at 09:05 AM.
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  #2  
Old 12-24-2016, 08:25 AM
tjk23 tjk23 is offline
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where did you find the videos
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Old 12-24-2016, 09:48 AM
ultraman6970 ultraman6970 is offline
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If you moved the saddle to the front and upper. Depending of how much you moved it forward you will be pretty much shorter and maybe even lower than before and probably thats why u look and feel even more upright than before. The other detail is your style, some guys can pedal good being on top of the bb like mr valverde, other ones like and need to be seated further back. No idea which are you.

Last edited by ultraman6970; 12-24-2016 at 09:51 AM.
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  #4  
Old 12-24-2016, 10:48 AM
stephenmarklay stephenmarklay is offline
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Originally Posted by tjk23 View Post
where did you find the videos
https://edsasslercoaching.com and he has a fit video on youtube.
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  #5  
Old 12-24-2016, 10:51 AM
stephenmarklay stephenmarklay is offline
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Quote:
Originally Posted by ultraman6970 View Post
If you moved the saddle to the front and upper. Depending of how much you moved it forward you will be pretty much shorter and maybe even lower than before and probably thats why u look and feel even more upright than before. The other detail is your style, some guys can pedal good being on top of the bb like mr valverde, other ones like and need to be seated further back. No idea which are you.
Very good point. That I moved it forward first and that is likely why I needed to go up.

I am really using the TI D method which makes sense to me. There are a lot of little checks and balances in it all of which I understand. No magic needed.
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Old 12-24-2016, 11:27 AM
ultraman6970 ultraman6970 is offline
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There is a like a proportions rule that I always forget, if you go forward X you have to go upper or lower Y mms... obviously depends of the seat tube angle aswell. Anybody knows the the proportion???
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  #7  
Old 12-27-2016, 11:46 AM
stephenmarklay stephenmarklay is offline
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I have been tweaking my seat position and it amazes me how much a 1/2 centimeter here or there can make.

I have really inched my saddle forward. I had been really far back but i realize that was not ideal.

I am still at about the center of rails on my brooks Cambium on a 25mm setback post with a 73 degree STA so I am not way forward but it feels like it.

I am seeing that position impacts my pedaling more than I thought. I wish I had a power meter with metrics to see that better.

It would seem that a power meter with force vectors could aid in fitting. Hmmm
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  #8  
Old 12-27-2016, 11:09 PM
giordana93 giordana93 is offline
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3:1

Quote:
Originally Posted by ultraman6970 View Post
There is a like a proportions rule that I always forget, if you go forward X you have to go upper or lower Y mms... obviously depends of the seat tube angle aswell. Anybody knows the the proportion???
pretty sure the cited ratio is 3:1, as in move saddle back 3mm, lower it 1mm. I doubt you would feel 1mm, but 3mm isn't much either. more realistic numbers would be in the 1-3cm of fore-aft needing 1/3-1cm of saddle height adjustment. These are just guidelines. I like to take 2 saddle height measurements. The easy to duplicate traditional one:middle of bb spindle along seat tube to top of seat (either the cupped portion or line given by a torpedo level straddling the nose and rear section of saddle if the saddle is curved) and for cross-checking variances of fore-aft and crank length: top of pedal (at bottom of stroke) to the point of contact with sit bones on seat
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Old 12-29-2016, 08:13 AM
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Ti Designs Ti Designs is offline
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Quote:
Originally Posted by ultraman6970 View Post
There is a like a proportions rule that I always forget, if you go forward X you have to go upper or lower Y mms... obviously depends of the seat tube angle aswell. Anybody knows the the proportion???
In bike fitting they (not sure who "they" is...) always try to simplify things down to a formula, or a rule of thumb (also don't know who's thumb...). That's where KOPS came from, who wants to spend the time learning about the effects of fore/aft position why you can just put their knee over the pedal spindle? More to the point, with a few simple formulas you can teach anyone how to fit a bike in a day or two. I can rattle off a few dozen fitting schools that do exactly that.

OK, here's my simple formula to answer your question: Pythagoras. Yes, he did live more than 2500 years ago, but he came up with this great formula to adjust saddle height (along with a few other things).

My real answer is an inditement of the factory that makes humans - it's quality control sucks!!! It makes tall ones and short ones, fat ones and skinny ones, not even the proportions from one body part to the next are the same. Car companies can make parts for their cars because they know the same part will fit on all of them - can't say the same for humans...

To adjust saddle to pedal relationship you need to understand range of motion and how balance changes on the bike. Range of motion changes in every direction: up, down, forward and back. Move the saddle back and you increase the distance from the hip to the far point in the pedal stroke (between 4:30 and 5:00). Move the saddle up and you increase the distance from the hip to the pedal at 6:00. Move the saddle down and you increase the needed range of motion at the hip as the pedal goes over the top. Moving the saddle forward decreases the distances, but it also shifts the center of gravity... The bottom line is it's not about one number and it's certainly nothing you can come up with a formula for. A good fitter doesn't ask you if you would rather have knee pain or back pain (I hope). They get it all right, or it's just plain wrong.
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If the pedals are turning it's all good.
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  #10  
Old 12-30-2016, 10:20 PM
ultraman6970 ultraman6970 is offline
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Interesting stuff...
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  #11  
Old 01-07-2017, 07:27 AM
Samyoooo Samyoooo is offline
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Quote:
Originally Posted by Ti Designs View Post
In bike fitting they (not sure who "they" is...) always try to simplify things down to a formula, or a rule of thumb (also don't know who's thumb...). That's where KOPS came from, who wants to spend the time learning about the effects of fore/aft position why you can just put their knee over the pedal spindle? More to the point, with a few simple formulas you can teach anyone how to fit a bike in a day or two. I can rattle off a few dozen fitting schools that do exactly that.

OK, here's my simple formula to answer your question: Pythagoras. Yes, he did live more than 2500 years ago, but he came up with this great formula to adjust saddle height (along with a few other things).

My real answer is an inditement of the factory that makes humans - it's quality control sucks!!! It makes tall ones and short ones, fat ones and skinny ones, not even the proportions from one body part to the next are the same. Car companies can make parts for their cars because they know the same part will fit on all of them - can't say the same for humans...

To adjust saddle to pedal relationship you need to understand range of motion and how balance changes on the bike. Range of motion changes in every direction: up, down, forward and back. Move the saddle back and you increase the distance from the hip to the far point in the pedal stroke (between 4:30 and 5:00). Move the saddle up and you increase the distance from the hip to the pedal at 6:00. Move the saddle down and you increase the needed range of motion at the hip as the pedal goes over the top. Moving the saddle forward decreases the distances, but it also shifts the center of gravity... The bottom line is it's not about one number and it's certainly nothing you can come up with a formula for. A good fitter doesn't ask you if you would rather have knee pain or back pain (I hope). They get it all right, or it's just plain wrong.

IF you lower the saddle and the foot flattens at the top you would open or keep the same hip angle plus the you become higher up relative to the bar that will also open the hip angle unless they are lowered aswell, yes?
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  #12  
Old 01-07-2017, 07:39 AM
stephenmarklay stephenmarklay is offline
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Man I am STILL tweaking my saddle. Even if I think I understand there are a lot of little nuances in how I am feeling and fitting.

I do think that that a the newest power meters with force vector analysis could aid in fitting. At least with the last 20%. I do wish I had one to see how things are changing with regard to how I am pushing on the pedals.
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  #13  
Old 01-10-2017, 05:05 AM
Samyoooo Samyoooo is offline
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Quote:
Originally Posted by stephenmarklay View Post
Man I am STILL tweaking my saddle. Even if I think I understand there are a lot of little nuances in how I am feeling and fitting.

I do think that that a the newest power meters with force vector analysis could aid in fitting. At least with the last 20%. I do wish I had one to see how things are changing with regard to how I am pushing on the pedals.
From what I learnt if you have the saddle too high you will just push on the pedals and same with the saddle being to forward with planter flexed feet

IF you want a power phase of 12-8 you have to set the saddle very low than what the conventional wisdom says can be 3-5 lower then what retul suggest saddle set with heels on the pedal with no hip rock and the saddleset must have the whole knee behind the pedal axle to get the push forward at 12oclock so you remove the deadspot and the saddle that is low enough must allow the foot to be flat, not heel dropped, but flat like 1-3 degrees or so that the hamstrings are a mechanical advantage to just draw the pedal back at 5 These no downward pressure at the "bottom of the stroke" you also have to soften the force at 3olock it will feel as if you have little pressure under the foot/pedal cadence if you drop the heel below the toes its an indication of pushing to hard and you create radial forces at 5-6 which contributes to no forward motion same with 12olock if the feet are toe down you will either push down at 12 or produce no force at 12. This way you do not use body weight to pedal its all contain in the legs and these no forces to move you on the rivet or pull on the bars

remember to not pull up but make sure the foot is dorsiflexed enough at 11 so start the push forward at 12 if not it wont be possible

This is if you want the most tangential force in the pedal stroke

Last edited by Samyoooo; 01-10-2017 at 05:11 AM.
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  #14  
Old 01-10-2017, 11:44 PM
giordana93 giordana93 is offline
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for the record, I answered the "formula" question about adjusting saddle height for changing set back values from a strictly mathematical pov. that is, if you want to duplicate a seat height modified only by a change in setback (which you could think of as changing the seat tube angle). I'm too lazy to look up my old trig math, but believe the 3:1 ratio is a rough estimate for a 73 sta. this is just to recreate the distance from pedals to sit bones and will of course vary depending on frame size and seat tube angle; nor does it take into account physiological variables such as hip flexibility, foot flexion, or cleat placement. In other words, the formula is not a fitter's formula, it's just a cheat sheet math shortcut
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