RM_guy

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Damn Yankees
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Nov 21, 2000
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North East USA
This is an excerpt from this thread http://dirtrider.net/forums3/showthread.php?s=&threadid=18216

When you take a turn, it’s a center of gravity issue. Anytime that you weight the pegs, whether when you’re turning or standing up, you effectively change the CG for the bike/rider. When you weight one peg or the other you are shifting the CG to the side of the bike that you are weighting.
When the bike is straight up and down, the CG is centered over the tires and the bike remains upright. When the bike is leaning in a turn (with no foot peg weighting) the CG moves off center and tends to make the bike lean further.
Try putting your bike on a stand. It stays there by it’s self with out tipping over because the CG is directly over the center of the bike. Now push the bike to the side and it starts to fall over. This is because the CG is now shifted to the side and starts to pull the bike over. If you are on the bike when it begins to tip, you would instinctively move your body to the opposite side (moving the CG in the other direction) to balance the bike and keep it from falling over.
The same thing happens when you lean into a turn except centrifugal force is acting on the CG to pull it back up. The combination of gravity pulling the CG down and centrifugal force pulling the CG to the outside of the turn, keeps the bike from falling over and it maximizes the downward force on the tire to maximize traction. So the right combination of speed (to control centrifugal force) and lean will get you around the turn without falling or sliding out.
Now we move into real life. In reality is very difficult to get your speed and lean optimized since the conditions in a turn are so variable. Friction through out the turn can change from loose to tacky dirt. This is where weighting the outside peg comes in. By weighting the outside peg you are shifting the CG to the weighted peg side. Since leaning the bike shifts the BIKE’s CG to the inside, weighting the outside peg counteracts that force and moves the bike/rider CG back over the tires which optimizes traction. You weight the peg more or less depending on your speed in the turn and the amount of bike lean.
So the idea is to maintain the bike/rider CG over the point where the tire meets the ground. Saying to weight the outside peg, press the tank with the outside knee, raise the inside elbow, sitting on the outside corner of the seat or to keep your body perpendicular to the ground are simpler ways of saying to move the CG over where the tire meets the ground.
When negotiating flat (no berms) or off camber turns it is more important to weight the outside peg since there is nothing to keep the tires from sliding out. Turns with big berms that are taken at high speed require less peg weighting.
I hope this helps.
 

Jeff Gilbert

N. Texas SP
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Oct 20, 2000
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I was playing this week with shifting body weight at a slow speed to get a feel of just how much affect it can have. Just by leaning the bike slightly and using my outside knee to lean into the tank makes a drastic difference in how the bike handles, makes it sorta flow through turns. The crap that I normally ride through is so bad that I usually end up standing on the outside peg to the point of almost lifting the inside foot off the peg.
 
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