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I'm fine tuning my seat height. Which is the best direction to work? Start high and lower until ?? I know that if your hips rock your seat is too high. Can you, as the rider, always tell that your hips are rocking? Are there other signs that you can look for which indicate your seat is to high/low? Is the best indicator of correct seat height "angle of the knee"?

Mike
 

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There are many sites that give techniques for setting seat height. The fundamentals is that your leg length sets the height. Variable inlcude crank length. There is a generally recognized angle of maximum extension that is optimum, so at the bottom of the stroke you have only a slight bend at the knee.

For fine tuning, assuming you have your seat set correctly for your leg length is to ride a number of hours over a week then move your seat up or down just a few millimeters, then ride the same rides again, noting how you feel and your performance change.

One rule of thumb is that if you ride and get knee pain toward the front of your knee your seat is too low. If the pain is behind your knee, your seat is too high. There is only a narrow range that works for a particular individual.

There are complicating factors as well. Ideally legs should move up and down like pistons, but some people have a tendency, possibly due to leg-length differences, to have a small rotational motion at the knee which cause joint stress. Cleat position and for the case of leg differences, wedges can be used to help correct such problems.

As far as basic seat height adjustment, if you have been riding with the seat too low (common among recreational riders who did not get properly fit by the bike shop) you are accustomed to such a position. If your seat is then raised to where it should be, ideally, you will have a sense that you are sitting too high. The reason for a lot of riding with one position is to get you acommodated to that position. Do not make a major change in position since it will throw you off.

Learn about proper fit (most high-end bike sites talk about fit). They all same basically the same things. Bottom line is you want your legs to get strong but you don't want your joints to be damaged.
 

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bad advice...

rubicon_nm said:
I'm fine tuning my seat height. Which is the best direction to work? Start high and lower until ?? I know that if your hips rock your seat is too high. Can you, as the rider, always tell that your hips are rocking? Are there other signs that you can look for which indicate your seat is to high/low? Is the best indicator of correct seat height "angle of the knee"?

Mike
The comon adivice to kep raising your saddle until your hips rock, then lower it a bit has to be one of the worst statements ever.

What you want is approximately a 30 degree included angle between the upper and lower leg, when pedaling with your foot in it's most natural position.

Jacking the saddle up real high can force an unnatural, extemely toes-down position. Jacking it up some more will force the leg to over extend at the bottom of the stroke. I've seen people with this extreme saddle height. They tend to pedal real slow due to the foot and leg over extending. Watch the pros sometime. It often looks like they have saddles set pretty low, but most often, they are pedaling a fast, smooth cadence.

Power = torque x cadence. If you can't maintain a high cadence, you won't make much power.

As a rough guideline, be sure you can drop your heel to a horizontal position at the bottom of the stroke, with your leg fully extended. Thse who pedal with a fairly level foot may want the saddle a bit lower (me) and those who favor a bit more toes down may want a bit higher. Keep in mind that it only takes raising the heel 2-3cm to go from a fully extended leg to a 30 degree included angle in the leg.
 

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Good advice

C-40 said:
The comon adivice to kep raising your saddle until your hips rock, then lower it a bit has to be one of the worst statements ever.

What you want is approximately a 30 degree included angle between the upper and lower leg, when pedaling with your foot in it's most natural position.

Jacking the saddle up real high can force an unnatural, extemely toes-down position. Jacking it up some more will force the leg to over extend at the bottom of the stroke. I've seen people with this extreme saddle height. They tend to pedal real slow due to the foot and leg over extending. Watch the pros sometime. It often looks like they have saddles set pretty low, but most often, they are pedaling a fast, smooth cadence.

Power = torque x cadence. If you can't maintain a high cadence, you won't make much power.

As a rough guideline, be sure you can drop your heel to a horizontal position at the bottom of the stroke, with your leg fully extended. Thse who pedal with a fairly level foot may want the saddle a bit lower (me) and those who favor a bit more toes down may want a bit higher. Keep in mind that it only takes raising the heel 2-3cm to go from a fully extended leg to a 30 degree included angle in the leg.
I agree, the "get the hips rocking and the lower" is a poor method. Most of the time it is difficult to assess whether the hips are rocking as the natural tendency is to extend the foot to compensate. This can be very bad as the Achilles tendon will take excess pressure from the back of the shoe and the popliteal tendon on the back of the knee can be strained.

The 30-degree of flexion is an ideal place to start. The problem is how to get there. Many physio-medical supplies stores sell a goniometer - basically a big thing to measure limb angles. Sometimes they can even be borrowed from medical friends. If bike is mounted in the trainer and the rider rides for a while to get comfortable, with assistance from someone else this angle can be approximated. The key is to stop pedaling, sit square and keep the foot at its natural pedaling angle during measurement. I should stress, this is far from exact but it will get you in the ballpark.

Other signs of high saddle-itis: 1) illiotibial band pain, this is the big tendon/fascia that runs from the buttock down and across the lateral edge of the knee. Not exclusive to high saddle (cleat angle can also affect this). 2) Sore crotch, if the saddle is too high then the rider will likely be bearing less weight on the sit bones and more on the perineum. Numbness, pain, chronic sores are all indicators of a high saddle. Signs of low saddle syndrome: 1) excessive loading of the inner (medial) quadriceps muscles. 2) Bouncing at very high cadences (different from rocking). 3) Pain below the kneecap - the patellar tendon.

It is interesting to observe the metamorphisis of a rider wrt saddle height. When I first started road riding and racing 14 years ago, I came from MTB racing. I ran a very high saddle. As the years have passed I have gradually come down in saddle height and also moved further back. This has helped me to ride higher cadences and I am much more comfortable for 4-5 hours in the saddle. Optimal saddle height really is a compromise between comfort and maximal ouput. That is why you see sprint-event track riders run very high saddles and Euro Pro riders run what almost seems like lowish saddles.
 

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C-40 said:
The comon adivice to kep raising your saddle until your hips rock, then lower it a bit has to be one of the worst statements ever.

What you want is approximately a 30 degree included angle between the upper and lower leg, when pedaling with your foot in it's most natural position.
Good stuff, C-40. Personally, I raised my saddle height until I still had a good spin but no longer felt like I was pushing down through bottom-dead-center of my pedal stroke. This is after a lot of experimentation, and I found that it gives me the most power with the least pain. What do you think of this method?

I also think that seat setback and reach -- which affect balance and hip angle -- are vastly underrated. I found a load more power when I shortened my reach, and my sustainable heart rate immediately rose -- probably due to recruiting more muscle. Hence, my search for a new, better-fitting bike that lets me do this with the proper seat setback and a "normal" stem.

Cheers,
Ari
 

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can't say...

There are a lot of possible methods that may work, but your mehtod sounds like it might result in a saddle that's too high. Yu might see how it compares to the methods I described. The improtant thing to to be sure that excessive height is not forcing the foot into an unnatural angle or over-extending the leg.

As for the reach affecting power significantly, I've never experienced. Were you changing the saddle fore/aft position to change the reach? If so, then you were really changing the knee to pedal relationship and that was the cause of the performance difference. Further forward generally promotes more spin and less torque. I always set my saddle first, then play with stem length. If I make a saddle fore/aft change greaer than 5mm, then the stem length usually needs changing to maintain the same reach. I judge adequate stem length by avoiding knee to arm contact while pedaling in the drops.
 

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It seems to work for me ... my knee angle is also "correct" at this point, but I find that a few mm makes a big difference in the "pushing through bottom" sensation, but not noticeable in the knee angle. I have big feet, and everyone's body is different, so YMMV ... it's just my method.

I've found this reach issue to happen with both changing saddle fore/aft and stem length. I had a 100 mm super-rise stem, and I had the same result as moving my saddle forward on a standard 110 -- only I had too much weight on my hands the 2nd way. I think it has to do with my hip angle, which was very closed with too much reach/drop, not with the KOPS relationship. Could also be the weight distribution issue from too much drop/reach in general.

Cheers,
Ari
 

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Discussion Starter #9
Guys, thanks for the replies.

The main reason that I'm working on my saddle height is that it is almost 1" lower than those returned by numerical methods like .883 of inseam or 1.08 of inseam. I use the "heel on pedal" method as my starting point and it results in a saddle height of 30". The numerical methods say ~30.9. This .9" delta is big enough for me wonder what's up. Is my anatomy different or is the inseam measurement bad.

When I measure saddle height I measure such that the tape splits the saddle rail and ends up in the low spot of the saddle.

I'm 5'11" and my bicycle inseam is 34.9".

I've done the "heel on pedal" measurement barefoot in an attempt to get rid of variance induced by the shape of the shoe sole. Shoes on or off saddle height still ~30 inches. I do add shoe/cleat thickness back in when barefoot.

It looks like I need to go to the LBS and have them measure my knee angle.

Mike
 

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cleat/shoe thickness

rubicon_nm said:
Guys, thanks for the replies.

The main reason that I'm working on my saddle height is that it is almost 1" lower than those returned by numerical methods like .883 of inseam or 1.08 of inseam. I use the "heel on pedal" method as my starting point and it results in a saddle height of 30". The numerical methods say ~30.9. This .9" delta is big enough for me wonder what's up. Is my anatomy different or is the inseam measurement bad.

When I measure saddle height I measure such that the tape splits the saddle rail and ends up in the low spot of the saddle.

I'm 5'11" and my bicycle inseam is 34.9".

I've done the "heel on pedal" measurement barefoot in an attempt to get rid of variance induced by the shape of the shoe sole. Shoes on or off saddle height still ~30 inches. I do add shoe/cleat thickness back in when barefoot.

It looks like I need to go to the LBS and have them measure my knee angle.

Mike
While I agree that nearly 1" is quite a big difference, it is important to note that the formulas like 0.883*inseam were derived quite a few years ago back when riders were just making the change from cages/straps toclipless shoes and pedals. Depending on your setup, you could easily have the distanced reduced by over 1 to 1.5 cm from the old school setup used in the derivation of 0.883*inseam.

FYI, I am 6'0" and my cycling inseam is 87 cm (34.25 inches, but I haven't measured this in years). My saddle height from C of BB along the seat tube is 75.8 cm (~29.8 inches). I use Sidi G5 Carbon shoes and Time Impact pedals which is a fairly low-stack setup.
 

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based on feel...

there are so many factors that influence the 'ideal' saddle height on a bike. Your shoes/pedals, pedal style, riding style, sag in saddle and etc...

For me, I just start with the 1.09*inseam formula and adjust from there... I move my saddle up if it feels too low and lower it when it feels too high. The range of possible saddle heights I have on my bikes are from 71ishcm to 72ish cm. There is no exact number so adjust it till it feels correct. The correct saddle height is one that does not hurt you while you ride.
 

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I'm fine tuning my seat height. Which is the best direction to work? Start high and lower until ?? I know that if your hips rock your seat is too high. Can you, as the rider, always tell that your hips are rocking? Are there other signs that you can look for which indicate your seat is to high/low? Is the best indicator of correct seat height "angle of the knee"?

Mike
One good start point is inseam lenght * 88.3%
86cm*88.3%=75.54cm

Perhaps you'll find something useful here
BikeFit - Road Bikes
 

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Depends on stack height of shoe and pedal, angle you hold your ankle (heal up or down, ankling...) longitudinal position of the cleat on the shoe, leg length, crank arm length.... Basically when warmed up and pedaling normally, the leg should get no straighter than a 20% bend at the knee. It's easiest to ascertain this from a photo or movie taken of you from the side when riding. High zoot fit systems like Retul and others use motion capture setups to do this.
 

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holy sh*t man...this thread was dead for SEVEN years! seriously...
That's some "Serious" digging to bring a 7 year old thread back to life ... Poor kittens :(
 

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Don't hate on the old thread resurrection, hate on the "similar threads" feature that people click on without realizing the age of a given thread. It's really a vBulletin fault rather than the poster imho.
 

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Don't hate on the old thread resurrection, hate on the "similar threads" feature that people click on without realizing the age of a given thread. It's really a vBulletin fault rather than the poster imho.
or just someone that felt like replying to a thread about something that's been discussed literally hundreds of times.
 

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A topic with "experts" and endless "right" ways of setting it.
Just one other consideration: max leg extension where crank arm is in line with seatube, not bottom of pedal stroke. In line is where leg is most extended. That's why it appears some guys look too low.
Not an absolute, just what seemed to improve my pedal stoke years ago.
You can probably find some "pro fit system" or "expert" to contradict this also.
 

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I set the height to where I'm comfy, then I go out riding with my allen wrench and set it again as needed.
 
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