Updated on 9 November 2026. The recommended products are available at the time of the update.
To choose a saddle, start with the distance between your sit bones and your riding position, then compare the width and shape of the seating area. The size should support your sit bones without getting in the way of your thighs: a wider or softer saddle is not automatically more comfortable. Codes such as S3 and L3 help you narrow down your options, but should always be considered alongside the model's dimensions.
How to choose
The sit bones are the two bones at the base of your pelvis that support you when you sit. The distance between them is a starting point, but the contact area changes as you lean your torso forwards and rotate your pelvis.
- Measure your sit bones. Measuring with a dedicated tool helps identify which widths to try. An impression taken at home can give you an indication, but is not enough to make a choice with certainty.
- Consider your actual riding position. An upright posture and a tucked position on the handlebars load the saddle differently. Assess how you ride on your usual outings.
- Check the usable width. The stated maximum width does not describe the entire supporting surface. The sideways curvature and the point at which the saddle widens also affect support.
- Avoid universal formulas. There is no fixed number of millimetres to add to your sit bone distance that works for every saddle. Follow the guidance for the individual model and check the result while riding.
- Try it with your own cycling clothing. Use your usual padded shorts and assess support, chafing and pressure after some time as well as when you first get on the bike.
Flat and curved shapes and length: what changes
A flat shape tends to allow more freedom to move forwards and backwards. A more curved profile, often called Waved, tends to offer a more defined seating position. These are pointers to check against your own setup, rather than rules that guarantee comfort.
Compare the length and shape of the nose too. Two saddles of the same width can feel different because they support the pelvis at different points or leave different amounts of space for the thighs.
- Central cut-out or channel: these can relieve pressure in the centre, but cannot compensate for an incorrect width or adjustment.
- Padding: greater thickness does not always mean more support. What matters is how the load is distributed.
- Adjustment: height, setback and tilt should be checked when you change saddles. Do not simply copy the nose position of the previous saddle.
- Rails: check clamp compatibility, particularly when switching from round rails to oval carbon rails.
If you keep searching for a different position or experience numbness, do not treat it as normal adjustment: stop the test and have the support and settings checked.
What S3 and L3 mean
In Selle Italia's idmatch system, S and L distinguish width categories; the number identifies a category linked to pelvic rotation and pressure relief needs. S3 and L3 are not bike sizes and do not indicate a men's or women's option.
Do not treat the code as a universal measurement, though. For the SLR Advan saddles featured here, S3 means 130 × 242 mm and L3 means 145 × 242 mm. The Flite Boost Gravel S3, meanwhile, measures 135 × 250 mm: even within the same brand, you need to read the dimensions in millimetres.
- First compare the model's width, length and profile.
- Check the presence and shape of the central cut-out separately.
- Do not automatically transfer a size between different brands.
How to compare Fizik ranges
To compare the Fizik ranges you are considering, start with the specifications for the exact version. The range name alone does not tell you which saddle will best support your pelvis.
- Intended use and position: check which discipline and posture it is designed for.
- Shape: compare the lengthways profile, sideways curvature, nose and freedom of movement.
- Dimensions: read the actual width and length, without looking for an automatic equivalent to S3 or L3.
- Central area and padding: distinguish between the channel, cut-out and seating area construction.
- Version and fitting: check the rail material and cross-section, as well as the stated weight for that size.
The selection in this guide does not include Fizik product specifications, so we cannot attribute dimensions or features to specific ranges or suggest reliable equivalents to the models below.
Our recommendations, available now
Selle Italia SLR Advan S3 130x242mm Saddle with Manganese Rail Black 188gr
Worth considering if you are looking for the S3 size, measuring 130 mm wide and 242 mm long. It has 7 mm round manganese rails and a stated weight of 188 g.
Selle Italia SLR Advan L3 145x242mm Saddle with Manganese Rails 190gr
Designed for road riding, racing and endurance, it lets you compare a width of 145 mm with the S3 from the same range, while retaining the 242 mm length. It has 7 mm round manganese rails, FLEX LFV cover and padding, and weighs 190 g.
Selle Italia SLR Carbon Saddle
A road option for those looking for a flat profile and a Superflow central channel. It measures 130 × 242 mm in S3 and 145 × 242 mm in L3; the 7 × 9 mm carbon rails require a check of the seatpost clamp.
Selle Italia Novus Boost Evo Gravel TM Superflow L3 Saddle
Worth considering for gravel if you want to compare a Waved profile with extra padding and a Superflow channel. It measures 145 × 245 mm and has a shock absorber between the shell and rails, with 7 mm manganese rails.
SMP Well S Gel Saddle
The product information lists it for a sit bone distance of 9.0 to 11.5 cm and for road, gravel, cyclocross and MTB, including on e-bikes. It measures 138 × 274 mm and has medium polyurethane padding with gel; versions with steel or carbon rails are available.
SMP F30 Saddle Black
An option for road, gravel, cyclocross and MTB, with a stated sit bone distance of 12.1 to 15.0 cm. It measures 149 × 295 mm and combines a black natural leather cover with expanded elastomer padding, with stainless steel or carbon rails.
You can compare other models in the Saddles collection. If you are also checking your position on the bike, read how to choose your road bike size: an unsuitable setup can also affect how you sit on the saddle.
Let's find the right support in Casapulla
Evolution Bikes is a family-run shop in Casapulla, in the province of Caserta, established in 1974 and now in its third generation, with a workshop, bike fitting and e-bike servicing. Drop in to discuss a trial or have your saddle adjusted, or ask us for advice. For shipping information, see the dedicated page.
Frequently asked questions
How do I know how wide my saddle should be?
Start with the distance between your sit bones and compare it with the model's guidance, taking your riding position into account too. There is no fixed number of millimetres to add that applies to every saddle.
What is the difference between a S3 saddle and a L3 saddle?
In the Selle Italia system, they belong to different width categories, with the same numerical idmatch category. For example, the SLR Advan saddles shown here are 130 mm wide in S3 and 145 mm in L3: always check the model's dimensions.
Is a softer saddle always more comfortable?
No: comfort depends on support, shape, width and adjustment. More padding does not automatically resolve pressure or chafing.
Does a central cut-out eliminate saddle pain?
It can help reduce pressure in the centre, but does not guarantee comfort on its own. If you feel pain or numbness, stop the trial and have the size, support and setup checked.
