Quote:
Originally Posted by SmartedPanda
(Post 2488338)
It's adding weight to one end of a stick, it's easier to gain momentum to shift it into gear.
Take a stick about 3 feet, and spin it with 1 hand, now add 1-2lbs to one end, and do the same thing, you'll see how easier it is to spin or twirl.
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I think you have the right idea, but you are saying it wrong, so let me geek out on the topic:
By adding weight to the knob it is harder to initiate a shift because the knob has a greater amount of inertia. Inertia is a description of an observation that things with mass tend to resist change, such that things at rest stay at rest and things in motion stay in motion, that is, until a force is exerted against the object. The greater the mass the greater the inertia, and thus, the greater a force has to be to alter the movement or lack of movement of that object. With that said, more mass to a knob means more static inertia.
Force equals mass times acceleration, so increasing the mass would increase the force required to initial a shift. Because a shifter is a lever, it is more correct to say that the torque (not force) would have to be greater with a larger mass because torque equals the force (or mass times acceleration) times the lever arm.
Once an object is in motion it has momentum, and because momentum equals mass times velocity, the more mass the knob has the more momentum it has. Also, the addition of velocity adds more inertia because it increases the force needed to change the objects position, so the object would have more kinetic inertia.
So why does any of this matter?
While speed of shifting is important for racing to spirited driving, a missed shift is not only bad for the car, but it hurts performance. And while there are several reasons why someone may miss their shifts, a shift that is not smooth is one of them. Adding mass to the knob can make the shift smoother because the knob in motion will have greater momentum and kinetic inertia, so the knob with be less influenced by external forces such as engine vibration or friction in the lever channel. Those external forces are more likely to cause error and an unpleasant feeling like waterskiing on choppy waters or rollerblading over a patch of asphalt vs smooth concrete.
A knob with more mass also has more static inertia, so the knob will likely vibrate less in the hand during times when someone is not shifting. I say likely because there is a possibility that the harmonics of the vibration of the car would match the mass of the knob and lead to greater vibration, but this is unlikely.
And just to use the above example, the idea SmartedPanda brings up is the idea that if you swing a tennis ball at the end of the rope on a windy day around in circles, you may see the wind contort the path of the ball, but if you used a heavier ball like a 3lb kettle ball, you will likely see far less to no effect that the wind has in altering the path of the ball. Again, because more mass means more motion which means more force is needed to change that path.
:cheers:
