blitz11
Well-Known Member
No offense, but the "transfer of center of gravity" argument is completely wrong. A first course in engineering mechanics would show that that is incorrect. If you stand up, YOUR CG rises. The bike's stays the same. Add them up, and the SYSTEM has a higher CG.AVGeek said:All good advice here, but a big one every one missed is to STAND UP! By standing up, you transfer the center of gravity from the seat to the foot pegs, and you can provide steering input with the strongest muscles in your body. Keep your knees slightly bent to help with the bumps. And until you get more dirt oriented tires, air down off pavement, it makes a huge difference to allow the tires to conform to the surface, rather than skip across the top.
What standing up does is create a mechanism by which you can impart a roll moment (or precisely, differential roll moment) to the motorcycle. By differential, i mean the difference between the force imparted on the left and right footpegs. By standing, you can also impart roll moments by pulling up/pushing down on the handlebar. You don't have that same vertical force capability while sitting down. (the handlebar is a pure moment which can be significant as well.)
Here's a thought experiment.
You're standing on the pegs. Both feet are putting equal force on the footpegs. you're putting zero roll moment on the motorcycle.
Now, lift one foot off of the pegs; all of the weight is on the other footpeg. If you weigh 200 pounds, and your footpeg is 1 foot from the longitudinal axis of the bike, you just imparted a 200 ft-lb roll moment onto the bike. You can't do that by shifting your torso location while sitting on the seat. You can do some, but not much. By standing, you can also impart roll moments by pulling up/pushing down (vertically) on the handlebar.
As you maneuver through the woods or trail, you guide the bike with the handlebars, but you affect your lean angle (and therefore propensity to turn) by shifting the load on your feet, imparting a roll moment on the bike. You now have more control authority and an additional degree of freedom to maneuver the bike. sitting, you have the same degrees of freedom, but much less control action due to torso movement. if you're sitting, you can't put a roll moment through the handlebar, either.
standing gives you control authority that you don't have while sitting. More control authority => more ability to guide / control the bike properly.