Setting up your motorcycle is simply adjusting the movable parts necessary for the rider to obtain the maximum control and most effective riding. We have to remember that no matter what type of bike you have, all motorcycles are handed with a neutral setup from the factory. This neutral setup makes for an easy maneuverability and a generally predictable handling on the limit, but a personal setup can always optimize the bike to your liking. No rider is alike and everyone has their own different riding style.
What kind of signs from your bike could you get if your setup is not well done? When you experience that the bike is hard to turn, when it wants to steer one way when you accelerate, or simply doesn’t respond to the inputs as you would expect it to. When this happens, it is the time to go back to the drawing board and try to find what element is out of balance.
Before doing anything to the neutral bike setup, you must be clear on certain things. It is important to find a balance in all the movable parts. Find a way that every element complements each other and work together according to your liking. That is the complicated part, finding an equilibrium in the setup. There are 3 important areas to have in mind: geometry, suspension and tires.
In the first post from this “Motorcycle Setup” series, we will focus on the motorcycle’s geometry.
The geometry of a bike influences its weight transfer characteristics. It is responsible for the way the motorcycle leans/turns, stands straight and accelerates correctly. To adjust the geometry, the distance between the drive shafts, height of the bike and angle of direction can be tweaked . In some competition bikes, the height and length of the position of the engine also plays a factor. The gyroscopic effect, is the physical effect that allows the bike to maintain its balance while it’s moving. When the rider leans into a corner, this effect is broken, to counter this, all masses in movement must be minimal. As speed increases, gyroscopic effects become stronger.
Physics tells us that more weight over the front tire will allow for more turning. When the rider brakes, weight is transferred to the front. This gives better turning, but if this is exaggerated, the rear wheel can lose traction. Having a shorter wheelbase distance can make the bike easier to maneuver, but quite nervous on the limit. The opposite happens with a long wheelbase. A long wheelbase makes the bike more stable and predictable. A longer wheelbase will make the bike lose turning ability or nimbleness. Finding a great balance consists on splitting the bike weight 50% rear and 50% front while standing still. Once the motorcycle starts moving, this balanced weight distribution will vary depending on suspension settings, spring stiffness and hydraulic settings.
A good example for geometry setup are drag racing bikes. These bikes extend the wheelbase as much as possible to distribute all the possible weight to the rear and avoid the front of the bike lifting up. This allows for a very stable and predictable handling for maximum acceleration in a straight line. Track bikes, in the other hand, have a shorter wheelbase to have more nimbleness around turns.
Hopefully you now have a better understanding of how the geometry in your bike affect its behavior and overall handling.
Until next week for the second part!