| The laws of physics work every time for good or | | | | seat. And, the part pulling down the slope of the |
| for pain; in this case for pain. | | | | seat is opposed by friction. If the force pulling |
| Good driving technique, mindfulness or knowledge | | | | down the slope of the seat is greater than the |
| of physics; either of these applied in this moment | | | | friction between a riders' bottom and the seat |
| could have prevented this accident. There are a | | | | cover, the rider slides backward. In this accident |
| number of factors contributing to this accident. | | | | the driver slid backward pushing the passenger |
| We will only discuss the physics portion here.To | | | | rearward and the passenger slid toward the rear |
| perform a wheelie the bike must be made to | | | | and off of the seat.Another complication was the |
| rotate around the center of the axle in the rear | | | | return of the bikes front wheel to the pavement |
| wheel. | | | | which caused a rotation around the bikes center |
| This is done by ove rthrottling and/or help from | | | | of gravity. This occurred at a very bad time for |
| the driver in terms of shifting the drivers weight | | | | the passenger, just when the passenger was |
| to the rear. It will be simpler to look at the case in | | | | unbalanced on the back of the seat. That rotation |
| which only over throttling occurs. The following is | | | | caused a little "flip" at the rear seat, flipping the |
| a conceptual explanation, not a detailed analysis of | | | | passenger off while in a vulnerable position.When |
| forces, vectors, torques etc.The driver over | | | | doing extreme stunts it is common sense and |
| throttles, this produces more torque at the | | | | courtesy to know all of the variables affecting the |
| sprocket than the resisting torque ((weight of | | | | outcome. The laws of physics operate whether |
| bike + rider) x gravity), so the front of the bike | | | | we want them to or not.Don't get on a powered |
| rotates upward. Fun so far.The thing keeping the | | | | vehicle with anyone you think does not value your |
| passenger on the bike seat is the force of | | | | live and health enough to find out.BrucePlease go |
| gravity, friction and the angle of the seat. When | | | | to the following link to view the basis for this |
| the bike is level gravity is pulling the passenger | | | | analysis. |
| straight down. But when the front of the bike is | | | | |
| elevated part of the force is pulling straight down | | | | View the movie clip "Outrageous Wheelie. |
| but another part is pulling down the slope of the | | | | |