priusenvy said:
Ever seen the rear tire on a high performance motorcycle? They're wider than the Prius tires. Do I need to go on?
Yes, and those bikes are all about acceleration, not cornering.
priusenvy said:
The tire contact patch on a wider tire (all other relevant variables held constant such as tire pressure and diameter) will be wider and shorter compared to a narrower tire. With a wider contact patch, the pressure will be more consistant across the face of the contact patch compared to a narrower, longer contact patch when cornering. This is why the wider tire can generate higher cornering forces at lower slip angles. Grossly simplified, a contact patch whose shape is longest in the direction it needs to resist force is better. Long and narrow is generally better for generating longitudinal acceleration (acceleration and braking), and short and wide is generally better for generating lateral acceleration.
You have it correct. The shape is longest in the direction it needs to RESIST force better. Long and narrow is good because it provides more SIDEWAYS resistance. Wide and short is better for acceleration because it provides more WIDTH of space to generate that force.
Example: Try pushing a snow shovel along concrete. Push it the 'normal' way, with the blade scraping along the wide direction in front of you. More resistance. More force needed. Now try pushing it side-to-side so it's narrow end is what is scraping. | -> vs. - -> It slides more easily. That's because even though the same surface area is sliding along the ground, you're making it slide differently. Now try 'turning' the shovel each way while sliding. The wide direction forward turns poorly, and tends to slip and slide as it does so. The narrow direction forward turns easily. (Like an ice skate, turning without slipping sideways.) A wide tire is like the shovel scraping the way it's meant to be used. Wide area providing lots of friction. A narrow tire is like the narrow end first. Turns on a dime, like an ice skate.
Conclusion: A wide tire is good for acceleration and braking, a narrow tire is good for cornering. Please note that this only counts for 'all other things equal' tires. As wider tires tend to be made to be higher performance, their sidewalls tend to be stiffer, and thus make them better suited for cornering than cheaper narrow tires. If you got high performance narrow tires, they would perform better than equal outside diameter wide tires. It really is all about the tire quality.
P.S. Please don't resort to personal attacks. It makes you look childish. I'm sorry, but John is one of the
most informed posters on here.
P.P.S. I studied aerospace engineering in college, and know all about force and friction. (Didn't get my degree, got sidetracked; completed 3+ years, though.)