This is the ultimate guide to determining your correct saddle/seat height on a bicycle, including how to set the fore/aft position of the saddle, as well as tilt. This guide focuses on setting the saddle height for a road bike, but applies equally to mountain bikes or anything else. One key note before we begin: there is no such thing as properly ‘setting your bike seat height’. However, there is such a thing as ‘setting your seat’. The difference? Seat height, fore/aft, and tilt should all be addressed simultaneously to ‘set your bike seat’. Get all three of these things right and you’re off to a good ride. Get any of the three wrong and it can lead riders straight back off the bike and to their golf clubs, ping pong racket or walking shoes.
How to set saddle heightLet’s begin by determining where your bike seat is now by taking a couple of measurements so you can learn from the changes you make, and what the difference is between a good seat position, a better position and the best position possible. The three critical measurements are saddle height, fore/aft and tilt. There are several ways to measure these, but the methods described allow anybody with a tape measure and a smartphone to accomplish this task. It’s good practice to document your starting position. It will come in handy in the future. The foundation for this measurement system is that it eliminates saddle-specific features. It doesn’t account for the differences between seats because there is no such measurement, but it does allow you to measure any saddle accurately, and that’s a great starting point.
1. How to determine your bike’s saddle heightMeasure the length of your seat from front to back and find a mid-point. Mark this spot on the saddle with a sharpie, small pen, chalk, etc. Use your tape measure to start at the centre-top of your saddle and measure in a straight line to the centre of your bottom bracket (ignore the seat tube angle). Some cranks are best measured from the driveside and some better from the non-driveside. Document your measurement to the millimetre (764mm, for example).
Measure the full length of your saddle to find a midpoint – this Selle Italia is 27cm (13.5 midpoint). Thomas McDaniel / Immediate Media
Mark the centre of the saddle so you can consistently determine your effective seat height. Thomas McDaniel / Immediate Media
Measure from the midpoint mark you made. The more accurate your measurements, the better your ability to understand the impact changes make on your comfort. Thomas McDaniel / Immediate Media
From the mark on the saddle to the centre of the crank – measure to the millimetre and use the side that provides the most accurate measurement (driveside vs non-driveside). Thomas McDaniel / Immediate Media
2. How to determine the saddle fore/aft positionPlace your bike against a wall, either in a stationary trainer or with the wheel in. Either way, make sure the bike is vertically perpendicular to the floor and horizontally perpendicular to the wall. Measure from the wall to the bottom bracket for measurement #1. Measure from the wall to the tip of the saddle for measurement #2. To calculate saddle setback, deduct measurement #1 from measurement #2.
#1 Measure a horizontal line from a wall to the centre of your bottom bracket. Thomas McDaniel / Immediate Media
#2 Measure horizontal from the same wall to the tip of your saddle – the diference between the measurements is your saddle setback. Thomas McDaniel / Immediate Media
3. How to determine saddle tiltBecause many seats have contours, the most favorable way to get consistent measurements is to measure the overall seat tilt. Place a piece of board over the seat and use your smartphone or inclinometer to find the overall seat tilt. Did you check to see if your bike was level before you started? I recommend documenting to the nearest 1/10th of a degree.
Measuring saddle tilt with a clipboard provides an overall angle, eliminating any deviations due to saddle contours – smartphones work great for this, but make sure your bike is level. Thomas McDaniel / Immediate Media
How to get the perfect saddle heightOnce you have your three measurements, it’s time to get started. There’s no shortage of ‘old school’ methods for seat height: the ‘Holmes method’, ‘Lemond method’, armpit on the saddle and fingertips to the centre of crank, and so on. To some extent, these have all been discredited by new schools of thinking in bike fitting, but that doesn’t mean they aren’t useful.
Determining saddle height with the heel methodAs a place to start, the ‘heel method’ is a very quick way to establish a baseline height. I still find it quite useful. This process can be done in a doorway, or better yet with the bike on a stationary trainer. Hop on the bike and place your heel on the pedal, in whatever shoes you plan on riding in. Pedal forwards or backwards, but do it slowly. If the saddle is too high, you’ll not be able to pedal smoothly without having to rock your hips from side-to-side, overreaching. Move your saddle down 1cm to 2cm at a time until this back and forth stops. Conversely, if it’s easy to pedal smoothly, try going up a few centimetres at a time until you have to start reaching for the pedals. Once you’re reaching, start edging your saddle back down until you find yourself in an ideal starting height.
How to use an app to determine your saddle heightLeave the ‘heel method’ in the rear-view mirror and try putting your foot on the pedal as you would when riding. If this means clipped in to clipless pedals then go for it. If you’re going the platform pedal route, then put about 1/3 of your foot in front of the pedal axle, and 2/3 behind. At this point, a stationary trainer is pretty much a necessity if you want to give a proper evaluation of your seat height. If you don’t have one, it’s still certainly possible, but it requires help from a friend and some fancy smartphone camera action. With the bike in a trainer, it’s time to snap a few photo/videos. I recommend downloading any one of a number of free apps for capturing and analysing motion. The app I prefer is Technique, but there are plenty to choose from. Any app that can create still images from action will suffice.
As a starting point for fore/aft adjustment of the seat, the centre of knee rotation is vertically above the pedal axle – experiment from there to find what feels best. Thomas McDaniel / Immediate Media
Ride your bike for a few minutes, as you would on any daily rides, adjusting your position on the seat till it feels comfortable. Once situated, you can begin capturing some imagery. The goal is to be able to quantify how much bend is in the knee throughout the pedal stroke, and to the approximate location of the centre of your knee. Generally speaking, at full extension (which is not 6 o’clock – more like 5 o’clock) 30 to 40 degrees of knee bend is the generally accepted range. If you’re feeling tension at the front of the knee or a large amount of work only from your quads, that seat height is a bit low. If you feel a dull ache at your low back, or you can feel your hips rocking a bit, that saddle is likely too high. Using the same images track to a point where the crank arm is forward-horizontal and look to the knee.
Determining seat height should be an active process – use ‘Technique’ or other motion capture apps to estimate your leg angle at maximum extension. Thomas McDaniel / Immediate Media
Approximate the centre of your knee, or the point where it appears to hinge. Where in relation to the pedal axle is your knee? In front, behind, or just above? If it’s behind, try sliding your seat forward a bit, until the centre of the knee is vertically in line with your pedal axle. The opposite of course if your knee is in front of the pedal axle. When you moved your seat forward or backward did you notice your seat height seemed to change? If you moved your seat forward to move your knee forward, you’ll likely need to raise your seat, too. The opposite is, of course, true if you moved your seat rearward.
When attempting to set fore/aft or height, pay attention to how you pedal: heel up, heel down, or somewhere in between – this affects measurements. Thomas McDaniel / Immediate Media
This little dance goes on until you’ve found something that feels smooth and balanced. No rocking back and forth, no muscle groups feeling like they’re doing more than their share of the work, and no aching knees or hips. Now take your bike out for a few short spins, and bring your hex keys with you. A few small tweaks can help finalise a good position, but don’t overdo the first couple of rides or you’ll be minimising the opportunity for proper and painless adaptation.
Make the saddle work for youAll of this has been under a major assumption that your saddle properly supports your sit bones. So, does it? Do you feel definitive pressure on the two sit bones of your pelvis? If not, it could be for two reasons:
- Your saddle shape or width aren’t matching your anatomical structure, or
- The tilt of the saddle isn’t enabling your sit bones to do their job.