By Jim Langley
As I ride around and spot other cyclists, I look at them, too. And I’ve noticed, like my friends did, that there are a lot of too-low seats out there. I see too-high ones once in awhile. But the low ones are easier to spot and more common, I think.
Too low a seat is a problem because it can cause knee pain, or even injury, fairly quickly, especially if you climb hills or push the pace. It also reduces your pedaling efficiency, since you aren’t able to use the full power of your legs. And, as the seat drops, the distance to the handlebars changes, possibly causing back or neck discomfort or pain as well.
Tip: When winter approaches, you may be planning to ride indoors on a trainer. It’s even more important to have the right seat height on a trainer because you’re more likely to sit in one position for extended periods, which can lead to injury faster if your seat’s not right.
Know your seat height
The easiest way to be prepared to check your seat height is to mark it or memorize it. That way, you can routinely check your seat with a tape measure or look at your mark. Some riders put a wrap of electrical tape around the seatpost to mark it. Black electrical tape blends in well with many seatposts and can hardly be seen. It’s also there if you ever need it for any on-the-road repair. But if tape clashes with your seatpost, or you simply don’t want a piece of tape junking up your baby’s looks, a line or dot from a Sharpie marker will last a long time, too.
I also memorize my seat height measurement, taking it from the top of the seat to the center of the bottom bracket. These two reference points are relatively easy to measure from.
Tip: Because I’d like to have a permanent mark, too, I know it’s tempting to want to scratch or notch your seatpost to mark it. But don’t do it because it will likely damage your seatpost and may even cause it to break. Maybe you’re lucky, though, and exactly four fingers fit beneath the seat. Something like that would be a nice gauge if it works for you.
Resetting your seat height
If your seatpost is marked or you know the measurement, it’s simple to raise it if you’re home with your tools. If you notice it on a ride, as long as you have the right wrench and have it marked, you can raise it right there. If you only know the measurement and don’t carry a small tape measure, you can ballpark it with the steps that follow, or look for an old mark since a post that has been in one spot for a while usually leaves some line or blemish on it.
Tip: Hopefully, when you try to raise your seat it will move easily. To prevent a seatpost from freezing, make sure it’s lubricated. If it’s steel or aluminum, use grease. For carbon seatposts and frames use what’s called “carbon assembly paste,” which is made just for carbon and has grit in it because plain grease would allow the post to slip. Be careful not to overtighten carbon seatposts.
Finding the right seat height
If you’re not sure exactly where your seat was, here’s an easy way to find the optimum height. Do it on a trainer or indoors in a doorway and have a friend or your spouse help. Put on your cycling shorts and shoes, mount your bike in the trainer or place your bike in the doorway, get on and hold onto the doorjamb to support yourself. Have your helper stand behind.
To find seat height, place your heels on the pedals and pedal backwards. You’ve found the optimum seat height when your legs are completely extended at the bottoms of the pedal strokes with your heels on the pedals. Have your helper watch for rocking hips, the sign that the seat is too high. Now, when you’re actually pedaling, you’ll have the perfect bend in your knees.
This is a great way to find a starting position. If it feels too low or high, adjust the seat up or down — but only slightly — to fine-tune the adjustment.
Tip: There are many high-falutin’ calculations you can perform to figure out your seat height, but this simple legs-fully-extended-with-the-heels-on-the-pedals method is quick, easy and almost always very close to perfect.
Would love to see an article on options for seat height when you’ve got a leg length difference (mine primarily due to hip and slight back curvature).
Mael Colium says
You may like to consider having a longer crank on your short leg. Then adjust your seat height. Make sure the length is accurate though – maybe an x-ray?
ralph schmook says
??? If there’s a leg length difference, a longer crank arm on the ‘short leg’ would add to the discrepancy at the bottom of the pedal stroke.
Allan Bridge says
As a coach I find most of the seat height adjustment issues are to do with weight gain or loss on the bum. If a rider has a propensity for weight change in that area, there is no alternative to constantly adjusting your seat height. With regards Christine and the bio-mechanics of leg stroke, adding additional padding to the Chamois on the long side will have the effect of shortening that leg, as will a thicker insole, if the cleat option does not work. It may well be a mix of these options will give you the answer.
Your cleat can also be further back or forward on the shoe to have similar effect. I don’t believe altering crank length will help you, in fact will give you more issues.
Mael Colium says
At the bottom of the pedal downstroke the forces are minimal before the upstroke, where leg length is not an issue. Leg length is an issue immediately after the overstroke as power is developed for the downstoke. Pedal stroking is an elliptical movement through 360 degrees over four stages. See here for an explanation https://www.active.com/triathlon/articles/a-breakdown-of-the-cycling-pedal-stroke .
Actually my leg length difference isn’t real (if you measured each leg) but rather caused by other bio mechanical issues (back and hip)… I found trying different compromises were somewhat effective, but then either one leg was hyperextending or the other was compressed too much (knee pain)… years ago when I was a more serious cyclist, during a professional bike fit, they inserted a shim under my cleat. That works for when I still ride road and have Keo cleats, but don’t know a solution for SPD along same lines… maybe an insole?
Overall, when just standing still, you can tell it’s almost half inch when you see where the hem of my shorts fall.
Anyway, I am not as avid of a cyclist as I used to be, partly due to this issue. Spending the money for a different crank on one side sounds too complicated and not justified for my purposes.
P.S. I no longer have the shim (it wore out)… and since it was years ago, wondered if that is still a solution these days and I should try it again (at least for the road bike).
Bike Fitness Coaching says
Most LLDs are functional not structural. Once you warm up, functional LLDs usually disappear
Mael Colium says
Ah ok, I understand your problem now.
Shims would be a better (and cheaper) solution. They are still very much in use from specialised, but there are probably more. A physio experienced with cyclists may be of help to you as I have used one such person to fix a saddle issue. Good luck.
THANKS FOR YOUR INPUT… I think that would probably work best, just have to find someone good at determining that… and also determine a solution for the other bike(s) that have spd instead of keo.
Greg Titus says
Why is this article entitled “Preventing Slipping Seat Posts” when it doesn’t discuss that issue at all, and is about determining proper seat height?
Jim Langley says
Good point, Greg.. while I did include a section with Tips for preventing seatpost slipping, the majority of my story is about making sure your seat stays at the correct height. I will see if we can change the title to Dealing with Seatpost Slipping. Not sure we can on this article but I’ll try. Thanks for the feedback.
Allan Bridge says
Regular seat height is great for the lean and mean cyclist. I coached a college team and several to do endurance for Ironman. I found that those with lesser training lost quite a bit of weight off the nether regions (bum) and often as much as fortnightly had to re-adjust seat heights to match this impact. My wife trained for ironman and lost 27kg over 6 months preparation, the effect on her seat height was almost 2 inches.
So my comment is to have recognition that erroneous seat height is more often related to weight variations than to seat post slippage.
Mael Colium says
True – this can happen with a regular rider between a seasonal layoff and more active summer periods. As I get older my rear end has less padding, so my saddle keeps heading South. Changing bibs/shorts with a new/different chamois can also make a difference that needs adjustment. It’s really a matter of ongoing small tweaks to find comfort and optimal position. I think nothing of hopping off at any point in a ride to tweak seat height/fore/aft until I’m happy on the day. My tools are handy to carry this out whenever the need arises.
Many riders I see are influenced by magazine pictures, thinking high saddles are the norm, and then wonder why they are sore and lacking power. It’s essential to do the heel cycling test very few weeks or so to get it right irrespective of how the saddle height “looks” from a fashion perspective.
Rick Schultz says
Another trick is for steel frames and aluminum posts and vice-versa. Never remove the post and after a years worth of sweat on the seat post coupled with galvanic action via dissimilar metals, it will never slip again. You won’t be able to remove it, but it will never slip. 🙂
Doug Kirk says
Watching a lot of bike racing this fall–Giro, Vuelta, l’Tour. I notice the pros’ saddles generally seem remarkably low (even when they aren’t in the “Super Tuck)!!. I’d like to read some professional insight about this. Coach Schultz? Mr. Langley? What do you say about this?
Rick Schultz says
The pros are catching on slowly. Old habits die hard. They are going to shorter cranks and Shimano yellow cleats and are now retiring at 40 vs 28 in the 60’s and 70’s. Professional cycling’s attitude is what is holding them back. They think they know better, even when they don’t, but, its slowly changing. For example, I spoke with Alex Dowsett awhile ago. He’s 6′ tall and he mentioned in his early career he went with 175mm cranks ’cause that’s what everyone else did, mid-career 172.5mm and now he’s sporting 170mm cranks. Just won a stage in Giro. He’s one of the more progressive ones.
Jim Langley says
Most pro teams have access to some of the best coaches and fitters in the world. So, even though, it might look like their seats are too low, I don’t think they are. Setting proper seat height is still done following the same rules as always.. But, I know what you mean about it looking low watching the pro races on TV and YouTube, etc. My theory is that it’s an illusion from the camera angle or perhaps the high cadence that makes it hard to see that their legs are actually extended more than they look.
Thanks for the comment!
Bob Myers says
A few years ago a mechanic informed me to make sure that I have a good layer of grease on the seat post to help prevent post slippage. This seems very counter-intuitive. It is explained by the grease filling in small irregularities in the post and frame, providing better traction on the mating surfaces. — Since I’ve been following his recommendation, I no longer have any issues with post slippage.
Pete Royer says
I use this method to get people in my spin class to move their seats, always up. I am amazed at how low people have their seat.
btw, I use black silicone as it is water proof and IMHO looks better than electrical tape.
Michael Chritton says
I assume this comment is tongue in cheek. My seat post clamp is rated for 7 nM so 25 would crush everything in sight.
Jim Langley says
This isn’t anything to joke about, Rick. If someone reads your comment and doesn’t realize you’re joking they could break their frame or seatpost or both.
Readers: Many components today have the torque (tightening) specification written on them. Be sure to look for that before tightening. If it’s not written on the part, google the component and you might be able to find directions for proper use. Most seatpost binder bolts are tightened to 4 to 7Nm.
Wayne Riley says
What about saddle position front and back along the rail? I am an insomniac and spend a lot of time on my trainer at night. My pace is such that I experience butt pain on the same saddle if I use it too often. To counter this problem, I have multiple seat posts with different saddles attached for quick switch-out. Saddles from different mfg’s require changing saddle heights and forward/aft positions depending on the saddle length and cushioning. I spend way too much time figuring out the best position for each setup.
Jim Langley says
That’s a clever solution having multiple saddles mounted on seatposts, Wayne, but I don’t think it should be so challenging for you to ride comfortably. For each rider and saddle, there should be an optimum fore/aft position. I have an article with the basic rules of bike fitting, including seat fore/aft positioning here: https://jimlangley.net/crank/bikefit.html (see Step #4).
I ride a lot indoors on a trainer – not due to insomnia but due to having to be to work early and not being able to ride except before work on most days. My indoor rides can last up to 3.5 hours – a long time to sit on a saddle. And as you know, on a trainer you spend much more time “planted” in the saddle than you do riding outdoors. There’s not much coasting on a trainer if any at all, either. Pretty much you’re pedaling the entire time.
I have experienced all kinds of saddle-related issues from riding so much on the trainer. Most common are chafing and saddle sores. It’s caused by constant contact for so long and the friction and also the heavy sweating from riding in place.
To deal with it, I use different things. If I know I’m going to ride for a long time and/or I already have chafing or saddle sores, I will wear two pairs of cycling shorts, a slightly looser pair over a tighter one. I will use a great product called Chamois Butt’r https://amzn.to/36aL0Yf to lube the shorts and myself. And, I will stand more on rides to get the pressure off the saddle.
I find that it’s not the saddle that’s causes problems for me and not its adjustment. Once it’s adjusted correctly, I sit on it the same place I would sit on any other saddle adjusted to fit me correctly. And, I use saddles that are all about the same shape. Maybe you are switching between different shape saddles? If so, I wonder if that’s part of the problem, i.e. by changing to different saddle shapes are you forcing your body to have to continually “break in” to the new/different shape?
That’s just a thought. For me, I stick with the saddle shape that works for me on all my bikes (Selle Italia SLR is the basic shape) and all my riding. Maybe something here will help you solve your discomfort and you won’t have to change your setup so often. Good luck!
Gary Keene says
Jim, I appreciate your work, but this article about seat post slipping is 95% about finding/setting proper seat height, not slippage. Only the tip about lubing metal posts/frames and using carbon paste for carbon frames touches on slipping. My comment/concerns touch on multiple versions of this issue: for example, on our bikes with metal frames/posts that use in wet conditions (road, touring and mountainbikes) I keep the posts lightly lubed and regularly cleaned and properly tightened, but still get some slipping / occasional twisting, On the carbon bikes, with carbon posts and metal posts, I use carbon paste on the latter, and still get slipping on the latter. Thanks for any feedback (gotta go watch the PA returns!)
Greg Titus says
Just a ‘quick tip’ about measuring seat height…I always hear about measuring from the center of the bottom bracket to the top of the saddle. Instead of trying to use the center of the bottom bracket as one of the fixed points (which I was always trying to ‘eyeball’ as to where it actually was), I simply subtract the radius of the BB from the total length of the BB/seatpost dimension, and use that shorter dimension. I take a yardstick, letting it rest on top of the BB, and measure from there up to the top of the saddle (along the center of the seat tube). No guessing as to where the center of the BB is, giving a very consistent measurement.
You also have to know where the center line of the seat tube intersects with the top of the saddle line in order to have a consistent measurement of seat height, since the seat tube does not run straight up vertically, but is angled back some 20 + degrees. Adjusting the seat fore & aft will affect where this point is, so once that’s figured out, you have two fixed points to work from to get the exact seat height you want.
this is an older post suddenly getting lots of replies and they are all going to my email inbox. How to turn off?