Other than the geometry of the frame, few things determine whether or not you’ll enjoy riding a bike more than its saddle. Fortunately saddles are easy, albeit potentially expensive, to replace. The best ones ride as if they are invisible, seamlessly glued to the rider, which will be different for every cyclist.
Types: For most purposes, saddles can be broken into two categories — racing and comfort. Keep in mind that racing saddles are not solely for racing and comfort saddles are not necessarily comfortable. The thinner, sleeker racing styles help prevent chaffing and allow for a full range of movement over longer, more intense rides. Comfort saddles provide added cushion for more casual, less active riding.
Rails: Located under the saddle, the rail is the suspension and attachment system of the seat. They are responsible for absorbing the jarring that results from hitting bumps on the road or trail.
Steel alloys like chromoly and manganese are designed to be lighter and stronger than carbon-steel, and are the most common type of saddle rail. They provide a good weight to strength ratio and value as well. Look for hollow tubes in these materials for reduced weight and more flex
On higher end saddles, titanium is the standard with carbon fiber becoming more and more common. Both have similar benefits of low weight and excellent shock absorption. Carbon fiber, specifically, is tops in these benefits, but also has the downside of being extremely expensive. Vanox, a titanium/ vanadium alloy, has been steadily gaining ground in the marketplace, and is marginally lighter, but definitely flexier than titanium as the added vanadium is a softer metal.
Shell: This is the body of the saddle, with nylon being the near universal choice. It provides more flex than plastic. Carbon fiber is often added for subtle changes in flex and some weight reduction while complete carbon shells offer the lightest weight and the biggest expense.
Many saddle designs work to reduce pressure on the perineum, the area of nerves and arteries in between the sit-bones. Both steady compression and sudden impacts can cause numbness and bruising to this area. Finding the right combination of features in a seat will help prevent discomfort and numbness as well as reduce or eliminate long-term problems such as incontinence, impotence and inflammation of the prostate.
Men’s and women’s versions will vary greatly as each genders anatomy is very different.
Saddle cover: Synthetic leather is near ubiquitous in mid-range saddles, but more expensive models will often use premium leather or higher quality synthetic materials. Durability between the two varies by manufacturer. Real leather tends to be slippery, but that isn’t necessarily a bad thing. Kevlar is sometimes used on mountain bike saddles and adds grip and durability. Reinforced corners or scuff guards are a superb option on mountain bike saddles.
Weight: For the average or even well above average rider comfort, not weight, should be the deciding factor in choosing a saddle. As a tiebreaker though, it’s a fantastic piece of criteria. For a comfort saddle roughly 350 to 600 grams is the average range. Carbon fiber racing models can weigh short of 100 grams, with 200 to 250 grams being an average range for a titanium (or similar) railed saddle.
Obviously comfort is king and the most important criteria. While shopping taking notes on dislikes from previous saddles will help in deciding on a new one.