Bicycle Seat Technology

Elements Of Comfort - Bicycle Saddle Foam

bicycle saddle
Firmly Padded Bicycle Saddle - PRS Alpha Black

The Function of Foam on Bicycle Saddles

Some cyclists and bike retailers believe that foam is the most important ingredient of a comfortable ride. Because its function is to provide a cushion barrier between cyclist and a hard plastic/carbon saddle base, it is undeniably a key element to comfort, yet a frequently misunderstood component.

The Traditional Bicycle Saddle Tests

Many consumers go to a bike store and apply two common tests to choose their saddle:

  1. The legendary thumb test.   Squeeze the foam between thumb and forefinger to measure how comfy the seat will be on the road. This test may work for buying a couch, but usually results in immediate disappointment following the first bike ride.
  2. The parking lot test.   Take a few laps around the parking lot and you’ll learn just how comfortable that saddle will be whenever you ride around a parking lot.

How to Choose a Bike Saddle - Foam & Density

Koobi's History with Foam

During Koobi’s first few years in business we had our saddles manufactured in Taiwan, by the world’s largest volume saddle maker in the world. Phil personally toured several factories in Taiwan and China to view the technology and quality standards. Taiwan’s  foam was like cake mix with a leaven added to get the mix to rise. It was poured into a saddle-shaped cake pan & placed into an oven to cook. The density of the foam was based on the amount of leaven used. The recipe was unreliable, and even when we specified a certain density of foam for a saddle, a high percentage was out of spec.

Koobi moved production to the Selle Italia factory in Italy. We have found Selle Italia to offer superior foam technology, injecting a precise amount of air and “cake mix” into an airtight mold. The precision guarantees a higher quality foam that is very consistent.

Bicycle Saddle Foam Behavior

Bicycle saddles are made with closed cell foam, a form of rubber with trapped air bubbles. The density of the foam is determined by the ratio of air bubbles to rubber. More air bubbles and less rubber makes foam feel softer initially, but as the foam compresses, the lower volume of rubber loses its support. The rate of foam collapse depends on the following variables:

  1. Density of the foam
  2. Length of the ride
  3. Weight of the rider
  4. Age of the bicycle saddle

In other words, the original density of the foam + length of ride + rider’s weight + age of the bicycle saddle, determine the rate of collapse. 


Foam Density and Rider Conditioning

It is generally believed that softness equals comfort, but this is true only as long as the foam maintains a cushion between the rider and the hard base. Firm density foam will hold up longest before collapsing. The longer the ride, the firmer the foam should be.  

If you are a distance rider, the conditioning of your “sit-bones” also increases, and a firm seat will feel most comfortable.  The casual and infrequent rider will prefer softer foam, since their sit-bones are not yet conditioned.

The Right Bicycle Saddle For You

Koobi offers a simple firmness/cycling scale to help you make the right choice.

Softly Padded Saddle:

Cycling less than 3 hours per week

Medium Padded Saddle:

Cycling 3-6 hours per week

Firmly Padded saddle:

Cycling greater then 6 hours per week

There is room for personal adjustment within this scale. If you weigh less than 150 lbs then you may be more comfortable on a softer saddle.  If you weigh more than 200 lbs then you may be more comfortable on a firmer saddle, no matter how much you ride.

Gel Bicycle Saddles

Gel has been used extensively in bike seats for about the last 10 years. Gel has a soft touch and thus does very well in the thumb test and the parking lot test. It has a trampoline type effect, spreading the pressure over the seat. One of the complaints about gel is that it weighs more and many cyclists don’t feel the added comfort compensates for the additional weight.  Another complaint is that some gels can harden over time and feel like a piece of car tire in the saddle.

Ultra Light Weight Bicycle Saddles

In the last few years, several companies have produced ultra light-weight bicycle saddles that feature a thin layer of dense foam on top of a carbon or plastic base. These bicycle saddles provide limited comfort by the shape and flexibility of the base. If your focus is extreme light-weight and you have a high pain threshold, then this type of saddle may work for you.

Triathlon Saddles :

Please see our article for triathlon bicycle saddles

More Elements Of Bicycle Saddle Comfort

Learn more about the elements of bicycle saddle comfort in this series of articles.