There are eight factors that determine ride performance of a bicycle frame which need to be explored and understood when purchasing a new bicycle. By taking each of these factors into account, the cyclist can be sure to make an educated decision in his next bicycle purchase. The goal is to optimize these factors to create the best combination of efficiency, handling and comfort.
Optimal Fit
The most important factor is finding the optimal fit. Most people relate a properly fitted bike to comfort, but that is just one of the byproducts. A well-fitted bicycle will be designed in such a way that the rider achieves ideal biomechanical efficiency resulting in maximum power transfer. The rider will also experience a greater sense of balance and stability on the bike when his optimal fit has been determined. Proper fit allows the rider to take in and digest nutrition more easily as well as creates a posture that allows for suitable oxygen transfer.
A professional bike fitting session is a wise investment to make before you choose a new bike or for your current bike, as it will save you from the costs (physical, mental and material) of an ill fitting bike.
Torsional and Lateral Stiffness
Torsional stiffness refers to the amount of twisting the bicycle tubes do under load (i.e.: your pedaling). Lateral stiffness is the side-to-side movement a tube or region of the bike goes through while under load. There is a fine line in defining how much a bike tube should twist or move. Just the right amount of movement is necessary, as this creates symmetry between bike and rider. We refer to this as “feeling one with the bike” or “dancing with the bike”. A frame that is too stiff will feel more like a wrestling match when put under intense loads. Custom manufacturers have the ability to design the perfect amount of stiffness in each tube on every bicycle they produce. It is because of this one-at-a-time approach to building that no two frames ride exactly alike, even though they may be the same model. If you are buying a stock bike as your next bike be sure to do plenty of test rides. Compare different materials and different brands. The custom option takes the mystery and chance out of the question of stiffness as the bike will be built for only one rider … you.
Vertical Compliance
Vertical compliance is the bike frame’s ability to dampen or soften the vertical shocks and forces it encounters. Vertical compliance is responsible for power transfer, improved handling and increased comfort. Out of the saddle efforts or riding on irregular road surfaces can often cause the rear wheel to lose contact with the pavement, resulting in a loss of power and stability. “Sticktion” is the industry term, (not to be found in Merriam Webster), that describes a rear wheel that stays planted during vertical forces. A wheel that sticks to the pavement and tracks consistently will deliver a smoother and more efficient ride. Vertically com- pliant frames help soften the shocks to your body caused by road vibration and impacts. There is plenty of research that indicates increased physical and mental fatigue due to small vibrations which travel through the bicycle frame.
Vibration Damping
Similar to vertical compliance, vibration damping results in a smoother feeling ride that preserves energy, and feels more comfortable. A stiffer frame often feels faster because the vibrations stimulate your brain and creates a feeling of exhilaration. Visualize riding at 20 MPH on a perfectly smooth road, nice! Now, visualize that the same road was just covered with millions of little pebbles. Imagine trying to maintain that 20 MPH. The vibrations will make you feel like you are going faster than 20 MPH. The truth is you are not going faster and you will tire more quickly.
Weight
The most frequently asked question by cyclists and non-cyclists alike is “How much does it weigh?”. This is the easiest concept to quantify and the easiest concept for marketing gurus to promote. The lightest bike is rarely the fastest bike. There is a point of diminishing returns when reducing the weight of a bicycle. Custom manufacturers who arguably build the best bikes in the world never design around the weight of the bike. They are fully capable of building the world’s lightest bike; however, stability, responsiveness, comfort, safety and impeccable handling are first and foremost on their list. These factors have the greatest influence on how fast a bike really performs.
Durability
Buying a bicycle is an investment, and, like most investments, we want to know how long it will last. Different materials are more resistant, or even impervious, to corrosion or damage from travel or racing. Ask questions regarding the frame’s life span and the manufacturer’s warranty. Most high-end bikes on the market today can last indefinitely when given proper “care and feeding.”
Frame Geometry
The geometry of the frame determines how straight the frame tracks, how stable the ride is, how efficient the shifting is, how quick the steering is, and how the rider’s weight is distributed. The geometry of a stock bike is predetermined so it is best to test ride various brands and models to determine which ride suits you best. A custom bike can be designed to deliver exactly the ride you are looking for. There are no compromises when purchasing a custom bike…you never need to settle for anything less than the perfect ride.