109% method...What am I doing wrong?
 

I've been riding for years and have used the 'heel pedal backwards' method to measure saddle height. I recently realized that I wasn't able to engage my hamstrings effectively so I raised my height about 2-3mm and felt more efficient. Also a slight knee soreness disappeared. I have no hip movement (reaching) and have a slight knee bend at the bottom of the pedal stroke.

I decided to try the 109% method. Wearing cycling socks and cycling shorts I measured my inseam (book in crotch to floor) at 74.5cm (3 times to be sure).
74.5x1.09=81.205cm. Measured from the pedal axle (pedal in-line with seat tube/furthest point from seat) to the top of the seat at center of seat post saddle attachment and found that 81.2 cm was 8 cm below where my seat is currently. I understand that any method is a starting point, but I expected maybe 1 or 2cm, not 8cm.

Did I do something wrong? Since the 109% method goes from the pedal axle to the seat, crank size is essentially irrelevant. The 8cm difference was consistent with my road, touring, ss/fixie and hybrid.

BTW...I'm 5' 10", 210 lbs. and wear pants with a 29" inseam.

I'd appreciate your thoughts. Thank you.

Something is off somewhere. Where does the 1 X 1.09 come from? So far as I know, Lemond's formula is .883 X crotch heigth, then add the crank length for the heigth from the pedal. The length of the foot enters into it also because a long foot effectively adds to leg length. So after the .883 measurement, the saddle may need to go up or down a cm or so and if you pedal toe down, that also adds to effective leg length. In any case just a bit of adjustment after the measurement and initial saddle heigth should be all that is needed. https://forums.roadbikereview.com/ge...it-183302.html

109% is from the pedal.

From the center of the axle to top of saddle is Lemond Method, .883 of the inseam (not 1.09 inseam).

It's also your inside leg length from snug in the crotch to floor. Not your pants inseam. As well formulas work well when your body is within the criteria of the person that came up with them. However they almost always leave someone out.

I truly appreciate that people give advice to fellow cyclists on this forum but it is frustrating when some contributors don't fully read the OP's message/request for information.

Where does the 1 X 1.09 come from? So far as I know, Lemond's formula is .883 X crotch heigth, then add the crank length for the heigth from the pedal.
I DON'T KNOW WHERE YOU READ 1 x 1.09. IT SAYS 74.5 x1.09. 109% FORMULA AND .883 METHOD ARE TWO DIFFERENT METHODS.

109% is from the pedal. From the center of the axle...
I MEASURED FROM THE PEDAL AXLE, NOT THE CRANK AXLE.

It's also your inside leg length from snug in the crotch to floor. Not your pants inseam.
I DID USE THE BOOK IN THE CROTCH MEASUREMENT, NOT MY PANTS INSEAM.

There is no question mark at the end of any of your sentences with 1 X 1.09 in the original OP. I've never heard of that method, nor do I take much stock in any method for fitting that involves crunching numbers. For me it's a visual along with trial and error.

No matter where you measure to or from, you will still have to do minor adjustments. It's how your bodies pieces parts feel that matter, not what a number says.

Question marks where???

You've never heard of that method but you know where the measurements are taken???

ADMINISTRATORS...PLEASE KILL THIS THREAD...IT'S NOT WORTH IT.

THANK YOU.

With 1300+ posts, I'd think you'd know by now to not ask questions on bike forums if you don't want answers that are not to your liking... People don't read, get used to it!

A formula is a starting point. Nobody is made the same way, and what feels good to someone might not to someone else.

I've used both the Lemmond .883 and the 109% method and in my case they are really close 80 cm inseam x109=87.2. 80cm x .883=70.64. I ride 172.5 cranks so the difference is only .64 and after subtracting the .3 they recommend for clipless pedals the numbers are even closer. Just wondering what your saddle height from center of bottom bracket is currently. The difference could just be that you are a toe pointer when you pedal.

Maybe not. I set my bikes up by feel and the few times that I have attempted to measure the BB to saddle distance or any of that, the numbers never jibed with any formula. So I promptly went back to not worrying about it. :thumb:

I have for experimental purposes used every type of formula (including the 1.09 you mention) that I've run across. For me, they produce widely different seat heights all of them resulting in a shorter seat height than my pro fit. (I'm not suggesting you or anyone else needs a pro fit.)

Good luck with what you seek.

I agree. It just seemed that a difference of +/- 8cm was way off.

Not worrying about it makes perfect sense.

The 109% method has me at 81.2cm but my saddle height currently is 89.5cm. I haven't tried the .883 method.
I am not a toe pointer, my feet are pretty flat through the stroke.

Well in your OP you stated that your pants inseam was 29". While I don't recall ever hearing of the 109% method. I certainly don't think any useful measurement for cycling fit will be based on pant size. However many are based on the length of your leg.

So please chill, your OP is not without plenty of statements that can be taken more than one way. And there is no direct question ask IMO.

It's not my wish to offend you, but you keep calling me out. Ignore me if I'm not helpful.

They always will be, because the two are mathematically the same with your 172.5 crank when your inseam is 32.4 inches. Which is a cycling inseam that's close to OP's "29 inch" pants inseam.

I don't know what OP's problem is, as he's obviously measuring something incorrectly or misapplying the formula, and then barking at people pointing out where his error might be.

My thoughts are, don't get hung up on numbers and calculations. They may be a starting point, but they are not a great way to fine tune saddle height, or any other part of bike fit. For seat height, take a look at this: https://www.stevehoggbikefitting.com...ard-can-it-be/