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Discussion Starter · #1 ·
I was wondering if several of you would chime in on how high your seat is in comparison to your inseam length.

While I realize this varies by the person including a myriad of factors including flexibility, body build, bike, etc.

I am trying to get an idea of where other people are at.

Measurement 1. Please give the height from the center of your pedal axle at the bottom of your pedal circle measured along your vertical tube to the top of your seat.

Measurement 2. your inseam as measured with your legs 6" apart from your crotch to the floor.


Mine is #1/#2 = 35"/32" or 109%.

My wife's is 34"/33" or 103%

Most people I have read recommend between 96% -110%.

Thanks for your help!
 

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Saddle height from center of bottom bracket to top of the saddle: 73 cm.

PBM: 84.5 cm.

Not sure I understand your measurements. If your saddle height total distance is higher than your inseam, you wouldn't be able to bend your knees. ??

Unless you meant from the ground to the top of the saddle, but that's not a standard measurement, and not what you said.
 

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Discussion Starter · #4 ·
Saddle height from center of bottom bracket to top of the saddle: 73 cm.

PBM: 84.5 cm.

Not sure I understand your measurements. If your saddle height total distance is higher than your inseam, you wouldn't be able to bend your knees. ??

Unless you meant from the ground to the top of the saddle, but that's not a standard measurement, and not what you said.

I didn't say from the top of the saddle to the bottom bracket, I said to the center of the pedal axle when it is in the bottom position or as woodys737 put it from the seat top to the bottom bracket plus your crank height.

I don't know what PBM is?
 

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I don't agree with the logic of using spindle to saddle length because I'm not pushing on the pedal too much at BDC (bottom dead centre). I'm pushing at 9.00 o'clock .

My cranks vary from 175 to 180 mm and I use the same saddle height for all - 81cm from the BB with a 90cm inseam. (just over the Lemond ratio). Giving between 109 and 110% depending on which bike I'm on.
 

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I don't agree with the logic of using spindle to saddle length because I'm not pushing on the pedal too much at BDC (bottom dead centre). I'm pushing at 9.00 o'clock .

My cranks vary from 175 to 180 mm and I use the same saddle height for all - 81cm from the BB with a 90cm inseam. (just over the Lemond ratio). Giving between 109 and 110% depending on which bike I'm on.
I think jack is just trying to get a handle on knee angle when you're the most extended ie BDC or thereabouts...I'm sure everyone reading knows how variable this can be considering all the factors which will determine amount of ankling. But for a ball park I get jacks angle.

Oh and to beat FTR to the punch, read up on what Steve Hogg says about self fitting for seat height and reach for starters. Easy to do...
 

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Oh and to beat FTR to the punch, read up on what Steve Hogg says about self fitting for seat height and reach for starters. Easy to do...
Awesome, someone has been following my posts. :D
To take it further, why would you care what your knee angle is?

But to play a silly game.
My inseam with bare feet is 34.5". With shoes it is 35.5".
My seat height is 37.5"/106.5cm (not really sure how you are measuring as I don't have a vertical tube on my bike.
Therefore the %age figure you are looking for is 108.7% bare feet or 105.63% in shoes with Speedplay pedals.
 

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My BB-to-saddle height has always been cycling inseam minus 10 (84 - 10 = 74 cm). This simple formula seems to work well for many riders. (Doesn't work so well for very short or very tall people, though).
 

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Awesome, someone has been following my posts. :D
To take it further, why would you care what your knee angle is?

But to play a silly game.
My inseam with bare feet is 34.5". With shoes it is 35.5".
My seat height is 37.5"/106.5cm (not really sure how you are measuring as I don't have a vertical tube on my bike.
Therefore the %age figure you are looking for is 108.7% bare feet or 105.63% in shoes with Speedplay pedals.
I found Steve back in 2009 while starting to rehab from 2 herniated low back discs. IIRC you were into Steve back then as well. Can't remember if you turned me on to him or someone else here on RBR...if you, then thanks.

As for the op and why care I guess you and I have learned it's the process that is important and the resulting angle is what it is. However, the op may connect the dots regarding something with what little information is gathered here. Just a small piece in the fitting puzzle so-to-speak. For me it's been a journey. Like you I have been messed up by a Retul (actually the human doing the fit but I digress) fit. It's kind of like everything in life, until you mess up, you don't know what you don't know. If my body had adapted to the Retul like a young kid I would not have the depth of knowledge I now have regarding my fit but the process itself.
 

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Awesome, someone has been following my posts. :D
To take it further, why would you care what your knee angle is?
That's an easy one. Because my knees will start to hurt with prolonged pedaling at certain angles, and won't at others. And because I get more power at certain angles and less at others.

It's hard to imagine not caring about knee angle. I can see not caring about the number assigned to it and getting the proper angle through other methods other than actually measureing the angle but by saying not to worry about knee angle is esentially saying where and how high your seat is doesn't mean anything.

For exaggerated example if my knee angle was at 180 (straight) or 90 at the bottom of my stroke I would care. You wouldn't?
 

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Jay, I have no idea what angle my knee is at the top middle or any other point of my pedal stroke actually.

All I know is it is comfortable for all day rides and powerful enough for crit racing.
Knowing about something or not doesn't change it's existance.
You apparently found the correct knee angle for you. Just because you don't what it is and didn't arrive at it by using a number doesn't mean someone shouldn't care about knee angles.
I'm not trying to pick a fight over it or get into semantics but I really do find "why would you care what your knee angle is?" to be kind of a weird question that, to me, implies knee angles don't matter and they most certainly do.
 

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Yes, agreed Jay.
Badly worded from me .
I guess I feel the OP is going about this the wrong way is all.
I don't see that fitting seat height to a knee angle is the way to go.
Arriving at a knee angle as a result of a functional seat height and setback is fine.
 

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Yes, agreed Jay.
Badly worded from me .
I guess I feel the OP is going about this the wrong way is all.
I don't see that fitting seat height to a knee angle is the way to go.
Arriving at a knee angle as a result of a functional seat height and setback is fine.
Okay got ya.
If the OP is just feeling his way into the sport I see where you're coming from.
I was kind of more looking at it from my angle which is having found the perfect knee angle (I think). If I was to get a new bike it would be a lot easier to just copy that knee angle rather than start from scratch and try to feel my way into it. Of course if the seat tube angle and seat were the same on the new bike it would be 6 or one half dozen of the other. But when they aren't the same copying the knee angles that have proven to work for you are the way to go IMO.
 
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