Seat Height

[Muners]

When measuring the seat height, should it be measured from the top of the seat to the middle of the crank?

 

[Roland Rat]

If by middle of the crank you mean middle of the bottom bracket, then yes.

 

[brianf7]

When measuring the seat hight from a bike fit you need Centre of the pedal axel to top of the seat at the widest point where you sit.
set that and go for a ride warm up and ride up a hill .
you should be able to just feel the full load of the pedal to the foot at bottom of the pedal stroke move the seat up or down untill it is correct then lower it a bit to alow for bad days when your body is a bit tight.

 

[blutto]

When measuring the seat hight from a bike fit you need Centre of the pedal axel to top of the seat at the widest point where you sit.
set that and go for a ride warm up and ride up a hill .
you should be able to just feel the full load of the pedal to the foot at bottom of the pedal stroke move the seat up or down untill it is correct then lower it a bit to alow for bad days when your body is a bit tight.

...there is another little trick that was picked from an old racer, and is, as yours, what I call a functional measurement( done while functioning as opposed to steady state measurements) ( which I think is important since optimum functionally is the goal of this process...and not just dropping a hapless rider onto a theoretically correct solution) ...and it became the final touch for a process that ends up measuring a lot of things...such as...where the sit-bones actually settle on the saddle...the pedal/cleat stack-height...the angle of your seating position...the thickness of your cycling shoe soles...and even the thickness of your chamois...crank-arm length...etc...etc...all of these things produce numbers that are, at best, guesses...but they do get you close if done with thought and care....

...the final touch, as passed on to me by that kindly old chap was this...if your saddle is too high you will move forward on the saddle ...as a result the sit-bones are pulled off the proper and comfortable points the saddle design has provided...and the narrow part of the seat becomes a resting point for a very sensitive part of or anatomy....ouch and not good for any number of reasons..

...if the saddle is too low you will slide off the back...not bad as above but inefficient...

...so the idea is to find a position that puts you in the sweet spot of the saddle and more importantly keeps you there...and then everything else is moved around/changed to accommodate that spot...such as handlebars....or top tube...

...this process is usually a matter of moving things by millimetres up and down but also front to back (because one movement affects the other )...keep in mind that the cumulative errors that occur when measuring the various systems that underpin your bike position could easily be 5 millimetres so dont be surprised if your raw measurements are out by at least that ( and lets not even consider the errors that occur when you measure your anatomy which could easily be on the order of centimetres and assume that this is either understood intuitively or measured properly...but if there are errors here they will be either gross errors that require a different frame size or if small will be addressed by the fix explained above )...

...now admittedly, this is a bit of a finicky system, but when you get that final position right, measure that point on the bike to death, and you are good to go for any changes in your bikes or their equipment...

...hope this helped...

Cheers

blutto

 

[forty four]

...there is another little trick that was picked from an old racer, and is, as yours, what I call a functional measurement( done while functioning as opposed to steady state measurements) ( which I think is important since optimum functionally is the goal of this process...and not just dropping a hapless rider onto a theoretically correct solution) ...and it became the final touch for a process that ends up measuring a lot of things...such as...where the sit-bones actually settle on the saddle...the pedal/cleat stack-height...the angle of your seating position...the thickness of your cycling shoe soles...and even the thickness of your chamois...crank-arm length...etc...etc...all of these things produce numbers that are, at best, guesses...but they do get you close if done with thought and care....

...the final touch, as passed on to me by that kindly old chap was this...if your saddle is too high you will move forward on the saddle ...as a result the sit-bones are pulled off the proper and comfortable points the saddle design has provided...and the narrow part of the seat becomes a resting point for a very sensitive part of or anatomy....ouch and not good for any number of reasons..

...if the saddle is too low you will slide off the back...not bad as above but inefficient...

...so the idea is to find a position that puts you in the sweet spot of the saddle and more importantly keeps you there...and then everything else is moved around/changed to accommodate that spot...such as handlebars....or top tube...

...this process is usually a matter of moving things by millimetres up and down but also front to back (because one movement affects the other )...keep in mind that the cumulative errors that occur when measuring the various systems that underpin your bike position could easily be 5 millimetres so dont be surprised if your raw measurements are out by at least that ( and lets not even consider the errors that occur when you measure your anatomy which could easily be on the order of centimetres and assume that this is either understood intuitively or measured properly...but if there are errors here they will be either gross errors that require a different frame size or if small will be addressed by the fix explained above )...

...now admittedly, this is a bit of a finicky system, but when you get that final position right, measure that point on the bike to death, and you are good to go for any changes in your bikes or their equipment...

...hope this helped...

Cheers

blutto

sliding off the saddle will be the least of your problems if you ride a lot and the saddle is too low many knee problems will come from all the compression not too mention significant loss of power and efficiency. honestly though it takes a year or more of riding to get to a good position as flexibility changes my position now would have killed me a few years ago. as a general rule if you experience knee pain in the front of the knee it is generally from a low saddle if there is tendon tension behind the knee you may be too high up. it was found with racers that a 96% extension was most efficient this is a higher saddle height than most use. for me i have found that higher is better lower seat heights cause me immediate problems. also pedals with free float help with all this. i have finally eliminated all knee issues related to fit.