Hi,
Quick question about seat height: When you have your seat height determined from a formula, such as Lemond’s, and the seat height calculated is supposed to be from the center of the bottom bracket to the top of the saddle, to WHERE on the top of the saddle are you measuring? The front? The middle? The back? I searched the forum and have found a (large) number of posts about saddle height, but cannot seem to find the answer for my question. Any help would be appreciated.
I am also interested in the answer. I have used the center of the rails for my measurement. That only works if you stick with the same seat though.
Measure along the seat tube angle to the aproximate top center of the saddle is how I have always done it. If your saddle is super far forward on the rails you may not end up at the center of the saddle though.
wherever your ass goes
.
Middle of the saddle because when you change saddle it’s the most consistent place, relatively independent from the shape of the saddle. Except if you sit only at the tip of the saddle, you will at some point sit in the middle.
Per Slowman
This is, by the way, a point roughly 17cm behind the nose of the saddle, for most saddles. This is about 3cm rearward of the point midway through the saddle (in most cases). This means that, on average, a difference of about 2 to 3 degrees of seat angle exists between an angle measured through the center of the rails versus the centerline of the saddle. Therefore, what “we” previously called an 80 degrees seat angle we will now call a 78 degrees seat angle, or thereabouts.
Take a level place it on your saddle then measure from the center of your BB to the top middle of your saddle or the bottom of the level.
x2. I’ve found Dan is spot on with this measurement, although I do have one saddle/bike (my 'cross bike) wherer 19 cm seems to be more appropriate. The “center of the rails” is pretty non-specific, I’ve found, and varies considerably among saddles. For whatever reason, 17cm seems to be about where most riders ride.
Most important is that once you establish the saddle height that works for you, use the same method of measuring when transferring this to other bikes. Consistency is crucial, the rest is just whatever falls out of the process of finding the optimal fit.
How do we take into account shoe/cleat/pedal thickness? What I’ve done is measured from the bike I did my professional fitting to where the crank arm is at full extension (roughly 5 pm on the drive side) and measure into the shoe to the top center of the saddle as discussed above. I’ve then tried to setup my cross bike and road bike with the same total seat height, as the crankarm length and pedals/shoes/cleats all vary. Does this make sense?
Isn’t the industry standard to apply the measurement derived from whichever formula you’ve used to the center of the bottom bracket to saddle? Surely there are too many variables to transfer the measurement from one bike to another as you have suggested, i.e. are you accounting for having a raised heel (or not) at the same position, crank length, or is full extension of the crank arm really 5pm or isn’t it more an extension of the downtube, more like 4pm?
Just thinking out loud!
Thanks for all the responses and help! 
So, when switching from a Fizik Arione to a Fizik Ares, you would still use the 17 cm? I think your seat height would be different. I know the “center of the rails” is not the best as rails are not all the same, but neither is the length of the seat.