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hi. i have been uncomfortable on my bike for the last bit, and started looking into bike fitters. i've also looked into the 'literature' and found the formula (which i believe is the "lemond" formula:

saddle top-to-bb distance = inseam X .883.

this puts, me, a 5'10ish rider with an inseam of 31-32 inches at a height of 69.3 cm. i measured my current height and it was 73.5 cm. my mountain bike, with its saddle in a position that i consider to be low enough for me to bail easily, but not necessarily the best power position, is at 68cm. this is surprising to me. i am, by no means, saying that i am right in my self-positioning--it's just surprising.

so my question is--where is your saddle height relative to this formula? 4 cm seems like a lot for me to be off. any recommendations? any success stories of lowering your seat (gradually of course) 4cms and feeling better on the bike? definitely it seems like i'll breath better with a less acute angle in the abdomen-thigh area, but what about power and minor things like that?

thanks for the input.

ross
 

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hi, I'm Larry
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Is it pants inseam or biking inseam measurement

There is a difference. For a lot of the sizing formulas you measure from the pubic bone down to the floor while standing with your feet about 6 inches apart. This can be another inch or more over your pants inseam size.

I checked where I have my seat set and it is within a half inch of the formula you posted when using my "cycling" inseam measurement. It is way off if I use my pants inseam size. My guess it is a good formula for road biking but not mountain biking.

It is normal to have a lower seat on a mountain bike for the reason you said. It is easier to bail and it is easier to get a little off the seat when hitting stuff on the ground.
 

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ralbert said:
saddle top-to-bb distance = inseam X .883.
..
so my question is--where is your saddle height relative to this formula?
ross
FWIW, I've never heard of this formula. But I went ahead and checked both my road bikes that I've been dialing in for the past year. Turns my measurements fits the formula exactly +/- 5 mm. Guess Lemond knows something about bikes.
 

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Every little counts...
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Take a good inseam measurement

ralbert said:
me, a 5'10ish rider with an inseam of 31-32 inches at a height of 69.3 cm.
You can't be 'about' in cycling inseam, you must be exact (to start). Go to an LBS and find one of those wooden inseam stands, crank that sucker up until your voice raises an octave.

AT home, with a textbook between your legs, get a good (wink) friend to achieve the same effect and mark the wall. Then, measure the wall.

Have someone watch you while you spin, do your hips rock? If yes, you might be too high.

Make small adjustments, take your time.
 

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Use Lemond as a starting point

Like any person who gives you fit advice, be it Lemond, Merckx, someone at your LBS, or someone on this forum... just use it as a guideline or starting point. Your body will tell you if the fit of your bike is not right. The key is being able to listen to it.

No matter what anyone tells you, take it as starting point advice and tweak it from there until you are comfortable on the bike.

I have read Lemond's book, Hinault's book, Eddy B's book, Friel's book.... blah blah blah... and I have worked in shops for the past 15 years... the one thing I learned from all of that is that nobody's fit advice is perfect. What works for Greg Lemond works for Greg Lemond. If it works for you, that's great, but it's also just lucky. You are an individual, and your fit will be individual to you. Start with solid advice from Lemond or a good fitter at an LBS, but don't be afraid to make changes either. It's your bike and you are the one riding it.

Russ
 

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ralbert said:
hi. i have been uncomfortable on my bike for the last bit, and started looking into bike fitters. i've also looked into the 'literature' and found the formula (which i believe is the "lemond" formula:

saddle top-to-bb distance = inseam X .883.

this puts, me, a 5'10ish rider with an inseam of 31-32 inches at a height of 69.3 cm. i measured my current height and it was 73.5 cm. my mountain bike, with its saddle in a position that i consider to be low enough for me to bail easily, but not necessarily the best power position, is at 68cm. this is surprising to me. i am, by no means, saying that i am right in my self-positioning--it's just surprising.

so my question is--where is your saddle height relative to this formula? 4 cm seems like a lot for me to be off. any recommendations? any success stories of lowering your seat (gradually of course) 4cms and feeling better on the bike? definitely it seems like i'll breath better with a less acute angle in the abdomen-thigh area, but what about power and minor things like that?

thanks for the input.

ross
You might want to start with an accurate inseam measurement. If your inseam is 31 inches, it's only a 1.5cm difference between your current mtb and the Lemond road saddle height. That's the same difference I have between my mtb and road saddle height. If it's 32 then it is a 4cm difference, which does seem like a lot.
 

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You talking to me?
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Agree entirely

It's just a starting point. FWIW - my saddle height is .881 x Inseam. This is just a coincidence that it's so close. I adjusted the height long before I read about Lemonds recommendation.

Bryan
 

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pay no attention...

Most saddle height formulas were developed in the days of toe-clips. They are not of much value today. Your inseam measurement is also not accurate enough to be of any value. If done properly you should be able to nail down your cycling inseam within .5cm. One of the easiest methods is to use a bike with a horizontal top tube and block up the wheels unitl you get weight bearing (saddle-like) crotch pressure when standing over the top tube in bare feet. Meaasure from the floor to the top of the top tube for an accuarate cycling inseam. Usually this method yields a larger value than most other methods.

Here's a good test for proper saddle height. Be sure that you can drop your heel 3-4cm below horizontal with the leg locked out at the bottom of the stroke. When the heel is raised to a more normal horizontal position, this should insure approximately a 15 degree angle between the upper and lower leg.

Using the .883 times inseam formula yeilds a 73cm saddle height for me, but I have mine set at 71cm, partially due to the use of speedplay pedals and Sidi shoes that have a low stack height. Formulas cannot take into acount the variation in shoe and pedal stack heights, which adds to their inaccuracy.

Another recommendation to avoid is raising your saddle until your hips rock and then lower it just a bit. This method can easily produce a saddle height that is 3-4cm too high, since most people first pedal in a toes--down, heel-up position to keep their hips from rocking.
 

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Ethical Nihilist
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Measurement

That's the inseam measurement in the bike shorts or bibs and in stocking feet. I have heard of it: Lemond used it in the 80s. I think he got it from his coach Cyril Guinard. Its a pretty good start point, but you should do what works for you. Also, take care making drastic changes in riding position. Better to make 1 cm increments until you get where you need to be.
 

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Every little counts...
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http://cycling.bsn.com/cgi-bin/ergobike.cgi?

Okay, the above link takes you to a web based calculator where the author tells you what the measurement is due to everybody's fit kits, and suggests alterations due to most (site is a few years old) pedal stack heights.

It is an interesting site to play with, I used it when buying a frame unseen over the net. As with most, use as a starting point and make small adjustments.

BTW, start saddle in a lower range and work up IMHO.
 

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eminence grease
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pretty darned close

by the formula, it should be 75.13, I set all my road bikes at 76. Interestingly, I've done the competitivecyclist fit calculator a couple of times and their recommendation is 78-79. I tried that, I hated it.

Based on the 1mm difference, I doubt I will change (given that I don't think I could even measure 1mm.
 

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One thing no one mentioned about LeMond's method....

Is that he pushed his saddle way back in it's rails:10/11CM- (nose of saddle behind the BB). So by moving his saddle that far back he is making it higher, so the .0883 worked for him, but it might make it too low for us common folk who don't ride with our saddle that far back. Greg had an incredible amount of hip and upper thigh strength, combined with long femurs. Most people can't generate this much power from this postion.(per "Training For Cycling", Davis Phinney and Connie Carpenter).

I set my saddle by a lot of experimenting and checking all the formulas, I'm almost right on the mark at .090. I set my saddle about 6 1/2-7 CM behind the BB, but different saddles cause for different settings, depending on the saddle.

I've never had my saddle so high that my hips have rocked, my lower back will tell me first if it's too high first.

That saddle behind BB has more to do about your STA. I use it so I can dail in my saddle if I change seat posts.

I never heard of KOPS in the old days, most guys just set their saddles 2-21/5 inches behind their BB and made a change if their body told them so. Saddle position is more a feeling you arrive at than a setting.
 

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yessir!

Much more of a feeling. Last night I measured the 3 bikes I ride most. They were remarkably close, but not identical. Measurements and formulas are starting points. The Lemond formula for seat height comes pretty close for me. But for setting up my own bikes, I'll put it on the stand and fiddle with it for a few rides.

I adjust the seat height by getting my left (shorter) leg straight out with my heel on the pedal and no leaning to the left.

I adjust the seat fore/aft by putting it all the way back, riding a few minutes on the stand, and sliding it forward til it feels right. I had the biggest difference here. The seat on my most recently set up bike was about 1 cm further behind the bottom brackket, so I moved it forward to match the others and up about 4mm.

I place the bars my riding with hands behind my back and leaning forward more and more. Ultimately I reach the point where I have to speed my cadence to keep from sliding forward on the seat. I put the brake hoods where my hands want to find them at that point. This takes care of both height and distance from the seat.
 

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classiquesklassieker
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What about ankling?

Even if there was one magic formula based only on your inseam measurements,
it seems that your amount of ankling, i.e., how much your ankle moves during
your stroke will also change what will make the correct seatheight. Or is this
(ankling) considered poor form?

For example, Armstrong ankles quite a bit when he pedals, meaning that his foot
is far from horizontal at the bottom of the stroke. On the other end of the spectrum,
Ulrich in his old days don't ankle at all, so his foor is horizontal at the bottom of the
stroke. If both of them used the same formula based only on the inseams, the
angles of their knees will be quite different at different portions of their pedaling.
 
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