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Tall rider Poll (saddle height to leg length ratio)(18 posts)

Tall rider Poll (saddle height to leg length ratio)Highgear
Apr 6, 2001 2:24 PM
I'm taking a poll to see if the .885 to .900 x inseam formula works in finding saddle height on riders with an inseam of 35" or longer. Measure your inseam: stand against a wall in stocking feet, place a 3cm thick book up tight into your crotch and square to the wall, have someone mark the wall at the top edge of the book, measure this mark to the floor. Measure your saddle height: Measure from the center of the crank bolt to the center of the saddle top. Now take the saddle height and divide it by your inseam, this #is what you should post. Also state crank arm length. Example 33" divided by 36.25 =.910 ratio. 175mm crank length. Thanks
Works for megimmeaminute
Apr 6, 2001 2:29 PM
Get some 180s. You'll thank me later.
re: Tall rider Poll (saddle height to leg length ratio)Bruno S
Apr 6, 2001 5:28 PM
Ok, here it is:

34" / 36.5" = 0.931

I recently raised the seat about one inch and I feel it better.

The crank length is 175mm. I have been thinking of trying out larger cranks (180) but the only ones I can find are Duraace. They sell for 210 and that has kept me from experimenting but if I hear from other tall people positive reviews for larger cranks I will change them.
You forgot pedals/shoes.12x23
Apr 6, 2001 6:54 PM
80.3cm/90cm = 89.22

I use Time pedals and Sidi G3 shoes. With Look pp296 and the Sidi's -
81.1cm/90cm = 90.11

175 cranks
You lost meStarliner
Apr 6, 2001 8:45 PM
Too much calculation for me... how about this method for determining seat height.....

Get on the bike, have either someone hold you up or do it against a wall. Put your heels on the pedal over the spindle, pedal backwards for several circles. Here's what you are looking for: when pedal is in down position, leg should be straight, knee not bent. Bent knee means increase seat height. While spinning, hips should be level and not be dipping down on the downstroke. If hips dip, then you are stretching too much and seat should be lowered.

That's it.
RE:You lost me........ No! foot length plays too big of a part.Highgear
Apr 7, 2001 1:46 AM
Especially for tall riders. My heels don't even touch the pedals without rocking side to side.
RE:foot lengthStarliner
Apr 8, 2001 7:56 PM
I'm 6'2 with size 13 feet and used this method OK. If you rock side to side with your bare heel on the pedal, try lowering the seat until you can spin smoothly, legs straight with knees locking on the bottommost pedal position, without rocking your hips.

Actually, this is only one step in a procedure I've learned designed to find the "optimal" saddle position. All the steps in their proper order are as follows:

First, set the tilt of your saddle so that it is level or having a slight nose high tilt when a level is placed atop.

Second, do the heel on pedal, spin backwards procedure as outlined previously.

Third, adjust the position of your foot in relation to the pedal spindle so that ball of foot to be over pedal axle. Put masking tape on side of shoe where ball of foot is, with a pencil mark denoting what you consider center point. Put foot into pedal and then take shoe off with shoe still connected into pedal. Mark on existing or another strip of masking tape a second line denoting present center of axle position in relation to shoe. Take shoe off and slide cleat forward or rearward to move axle centerpoint to that of ball of foot.

Lastly, adjust seat fore-aft position so that, when crankarm is in forward-horizontal position, bony part of lower knee is directly over pedal spindle. A helper is good for this one.

Nothing is ever written in stone except for our eventual gravestones, so I'd suggest dialing in your bike first, then riding it for a while, and then if you must, tweak one or more of the settings as you see fit.
34.5 inseam, ratio = .863 (nm)Kerry Irons
Apr 7, 2001 5:39 AM
re: Tall rider Poll (saddle height to leg length ratio)Mel Erickson
Apr 7, 2001 6:33 AM
The Klein web site has an interesting treatise on the whole subject of bicycle fit. Check it out.
Not exactlyGroucho Marx
Apr 7, 2001 10:11 AM
31.0" / 36.0" = 0.861

I guess this means that according to the formula, I should have a slightly higher saddle.

Is this something you developed? Who developed this formula?
top secret seat height formula revealedjohn de
Apr 7, 2001 10:43 AM
i go for 83.3 of inseam and im only 5'8"...if you decide to move your seat do it very sloooowly..millemeters at a time..i say this because my knee is fungled now and i think my giant seat height jump probably is responsable
Not exactlyBruno S
Apr 7, 2001 11:20 AM
It seems that you could have the saddle much higher. Experiment by raising it about 1/3 of an inch at the time.
Answer to Groucho's questionHighgear
Apr 7, 2001 6:08 PM
This ratio (.885 to .900) is taken from the findings of Greg Lemond, Bernard Hinault and Armel Andre's research. I find that the the problem is that it was developed using measurments taken from pro cyclists in Europe, there are very few pro's in the six footer range.
re: Tall rider Poll (saddle height to leg length ratio)DaveG
Apr 7, 2001 10:13 AM
89cm inseam, 78.7 seat height = .884 ratio. That's with 175 cranks and Look pedals
92.4 cm inseam, 98cm saddle height: .94 ratio. 175 mm cranksSteve Davis
Apr 7, 2001 4:23 PM
S. Davis. Do you mean 86.85 saddle hight?? (NM)Highgear
Apr 7, 2001 6:13 PM
Oops. I measured to center of pedal boltSteve Davis
Apr 8, 2001 12:57 PM
My inseam is 92.4 and the distance from the top of my saddle to the center of the bottom bracket is 81 cm.

Lemond's book recommends that the distance between saddle and center of bb can be determined by muliplying your inseam by .883. Interestingly, he states that the distance is unaffected by the length of the cranks. I don't quite understand his reasoning here. Do you?
Oops. I measured to center of pedal boltHighgear
Apr 8, 2001 1:34 PM
I'm unsure of this. Maybe because with the .883 is a little on the low side and a 5mm change in a longer crank length wouldn't put a rider into the overextension zone. My inseam is 92cm and you are .5cm longer but ride 3cm lower than me I pedal flat to a little toe down style. I'm curious, do you have lots of bend in your knee at the bottom of your pedal stroke?