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Discussion Starter · #1 ·
Other than "Wrench Science" any others you would recommend to double check where
I'm at & if my settings are in the ballpark of the norm? I realize it's personal thing
but just to get a point of reference of where to start is my goal.

Thanks
 

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Here you go

Here are several frame fit calculators.

http://www.zinncycles.com/fitsystems/default_ie.aspx
http://www.bsn.com/cycling/ergobike.html
http://www.coloradocyclist.com/BikeFit/index.cfm
http://www.sheldonbrown.com/harart-frames.html
http://www.rivendellbicycles.com/frameinfo/Frame_Sizing.htm
http://www.peterwhitecycles.com/fitting.htm
http://www.wrenchscience.com

For adjusting the fit of the bike, there are roughly five starting points:

1. Seat height (top of saddle to center of pedal axle) at 108-110% of inseam.
2. Saddle parallel to ground.
3. Saddle fore/aft adjusted so that a plumb bob from the bony protrusion just below the kneecap passes through the pedal axle when the cranks are horizontal. This is known as KOPS (Knee Over Pedal Spindle)
4. Front hub axle obscured by the handlebars when riding in your "regular" position (drops, hoods, or tops).
5. Top of handlebars 1 to 4.5+ inches below the top of the saddle depending on your flexibility and size.

These are all starting points for "average" proportioned people, and many folks like to move away from these starting points as they learn what makes them more comfortable, powerful, or efficient. For example, the KOPS position range is typically +1 to -2 cm, depending both on your personal physiology (long femurs tend to push the saddle back) and pedaling style (spinners move the saddle forward, pushers move the saddle back). You want to get the fit of the frame as close as you can, then do minor adjustments with the stem, seat post, saddle position, etc.

A lot of this is personal comfort, and we all tend to adapt to a given position over time. For example, a given stem length may be right for you, but it may feel long at first. I use the "handle bar obscures the front hub" rule for my fit, but others claim better position (for them) with the hub in front of or behind the bar. Plus, if you look down without moving your head, you get a very different view than if you tilt your head to look at the front hub. I'm 6' tall and ride with 11.5 cm drop from saddle to bar, probably more than most people would like but fine for me. Some are suggesting zero drop from saddle to bars - it's about comfort, efficiency, and aerodynamics. No calculator is infallible, so look at the different results you get to see where there is consensus among them. I would suggest riding some miles (over 100 total, and over 500 would be better) and see if you adapt to a given position. There are no hard and fast rules, just general guidelines, when it comes to these things.

Just as important as your size is your flexibility. If you have a stiff lower back, you may not be able to lean over and stretch out as much. If you are very flexible, you may get away with a longer top tube, with the stem in a lower position. Over time on the bike, too, you may become more limber, or at least become accustomed to being lower and stretched out. So, your first 'real' bike may not be anything like what you will want 5 years from now.
 

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Discussion Starter · #4 · (Edited)
Kerry Irons said:
Here are several frame fit calculators.

http://www.zinncycles.com/fitsystems/default_ie.aspx
http://www.bsn.com/cycling/ergobike.html
http://www.coloradocyclist.com/BikeFit/index.cfm
http://www.sheldonbrown.com/harart-frames.html
http://www.rivendellbicycles.com/frameinfo/Frame_Sizing.htm
http://www.peterwhitecycles.com/fitting.htm
http://www.wrenchscience.com

For adjusting the fit of the bike, there are roughly five starting points:

1. Seat height (top of saddle to center of pedal axle) at 108-110% of inseam.
2. Saddle parallel to ground.
3. Saddle fore/aft adjusted so that a plumb bob from the bony protrusion just below the kneecap passes through the pedal axle when the cranks are horizontal. This is known as KOPS (Knee Over Pedal Spindle)
4. Front hub axle obscured by the handlebars when riding in your "regular" position (drops, hoods, or tops).
5. Top of handlebars 1 to 4.5+ inches below the top of the saddle depending on your flexibility and size.

These are all starting points for "average" proportioned people, and many folks like to move away from these starting points as they learn what makes them more comfortable, powerful, or efficient. For example, the KOPS position range is typically +1 to -2 cm, depending both on your personal physiology (long femurs tend to push the saddle back) and pedaling style (spinners move the saddle forward, pushers move the saddle back). You want to get the fit of the frame as close as you can, then do minor adjustments with the stem, seat post, saddle position, etc.

A lot of this is personal comfort, and we all tend to adapt to a given position over time. For example, a given stem length may be right for you, but it may feel long at first. I use the "handle bar obscures the front hub" rule for my fit, but others claim better position (for them) with the hub in front of or behind the bar. Plus, if you look down without moving your head, you get a very different view than if you tilt your head to look at the front hub. I'm 6' tall and ride with 11.5 cm drop from saddle to bar, probably more than most people would like but fine for me. Some are suggesting zero drop from saddle to bars - it's about comfort, efficiency, and aerodynamics. No calculator is infallible, so look at the different results you get to see where there is consensus among them. I would suggest riding some miles (over 100 total, and over 500 would be better) and see if you adapt to a given position. There are no hard and fast rules, just general guidelines, when it comes to these things.

Just as important as your size is your flexibility. If you have a stiff lower back, you may not be able to lean over and stretch out as much. If you are very flexible, you may get away with a longer top tube, with the stem in a lower position. Over time on the bike, too, you may become more limber, or at least become accustomed to being lower and stretched out. So, your first 'real' bike may not be anything like what you will want 5 years from now.
Thanks for all the info..I can tell a lot of time went into your post!

RE: the saddle height at 110% of inseam...my inseam is 34" so add 3.4 and you have 37.4"= 94.996... that would be well above my 76.5 cm that I'm at right now....I'm 6' and am riding a 57 Cannondale (center to center).

update:

I re-read your post and realized you were going from the center of the pedal, not the crank...thanks!
 
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