Claviger
Aspiring Student
- Joined
- Jul 25, 2014
- Messages
- 6,934
- Location
- Olympia Washington
- Ride
- '21 Z H2, '14 R3R, '02 Daytona 955i
@1olbull or others who are good at geometry (I'm terrible at it). I am trying to mentally digest some lean angle stuff. Basically, why do I have to lean so much more on my R3 for a given speed than smaller bikes. A few things are obvious
1: Wheelbase
2: Tire width
3: Steering Geometry
So from what I've read:
1: Wheelbase, effects mostly transitional states, and has a very minor effect in steady state cornering. While the tangent drawn through the axles to center of the circle of a turn will be slightly greater on a longer wheelbase bike, the effect is small.
2: Tire width, from what I've read, has the most effect on steady state cornering lean angle. If that's the case, then a larger tire would need to be leaned over more to track around the same radius curve as a narrower tire, however, the wider tire will simultaneously have a larger contact patch while doing so. The greater contact patch will translate to some increase in traction, providing the ability to lean even further until you touch hard parts down. Alternatively, it would allow throttling out harder and earlier than the narrow tire bike, provided, the increased speed still allows you to stay on a radius that will complete the corner.
3: From what I've read, this has basically no effect on lean angle during steady state cornering, but instead only effects transient action.
Putting that all together, is there a way to calculate what the theoretical (combined rider + bike) lean angle would be for a given turn if you know the geometry numbers and radius of the turn, for example the one below at 75mph?
1: Wheelbase
2: Tire width
3: Steering Geometry
So from what I've read:
1: Wheelbase, effects mostly transitional states, and has a very minor effect in steady state cornering. While the tangent drawn through the axles to center of the circle of a turn will be slightly greater on a longer wheelbase bike, the effect is small.
2: Tire width, from what I've read, has the most effect on steady state cornering lean angle. If that's the case, then a larger tire would need to be leaned over more to track around the same radius curve as a narrower tire, however, the wider tire will simultaneously have a larger contact patch while doing so. The greater contact patch will translate to some increase in traction, providing the ability to lean even further until you touch hard parts down. Alternatively, it would allow throttling out harder and earlier than the narrow tire bike, provided, the increased speed still allows you to stay on a radius that will complete the corner.
3: From what I've read, this has basically no effect on lean angle during steady state cornering, but instead only effects transient action.
Putting that all together, is there a way to calculate what the theoretical (combined rider + bike) lean angle would be for a given turn if you know the geometry numbers and radius of the turn, for example the one below at 75mph?
