I love it when topics get resurrected, and especially when I have just discovered the technique, literally yesterday...it forces me to relate my newfound exuberance not only to the "what" but also the "why." I am not a proud author and I am seriously interested in all responders. Why? Because if what I know to be true as outlined below proves false - I need to know ASAP.
First, kudos to the CSS Coaches who asked the poignant question and provided the illustrative example: i.e. Cobie's 'stirring the pot' getting the topic back on track, "Does it matter which peg is weighted?" and then HotFoot's barbell example. Nice tag team.
The OP's question was "Why weight the outside peg vice the inside?" and then we got into locking the body, Newton's Laws and "vector mathematics."
We do "things" on the bike - perform techniques - to aid our riding. So I reckon the better question might be what are the advantages to weighting the outside peg over the inside peg?
1. Many of you have written it helps you 'lock-on' to the bike with less fatigue than other techniques.
2. Others have written that it helps focus major muscle groups in the steering process - as per TOTW2, Keith mentions it is like 'power steering' yielding less fatigue. Also Keith tells us in TOTW2 that "pushing under the bike" is not a good technique for asphalt based motorcycles.
3. Others have advocated that it only serves to 'pickup the bike' upon the exit.
4. My experience from a one-day experimentation over 5 hours and 300 miles is that in the great "ballroom dance" that is elegance & finesse motorcycle riding, I am in a much better position to lead the bike around the dance floor when my "touch points" on my girl are correct AND effective.
Those are 3 GREAT reasons (4 if you count mine) to weight the outside peg! Are there ANY disadvantages? I haven't read about one or personally found one yet. The comment about riders who are "inseam challenged" and lift their foot off the outside peg yet still win races doesn't mean this is a bad or overrated technique at all - just that it doesn't have to be used to win races.
Of course, being the dedicated riders we are, always wanting to learn more about riding, the why is always what matters - because that is how we remember to do things.
It's great to discuss the Center of Mass (CM) and Center of Gravity (CG), but what seems to be missing from most of the posters' train of thought is the "moment of torque" surrounding the application point relative to the CM on the bike - hence HotFoot's outstandingly simple barbell example. What is at play here is the delta between gravity operating on the Center of Mass, and the torque - or 'moment arm' - acting on the bike around the bike's CM due to pressure applied anywhere other than the CM.
To calculate this moment arm, or torque, I present the formula t=rFsin(α) where r is the radius distance from the CM, F is the actual Force and α is the angle of r.
So, if Keith weighs 180 pounds (full gear & the math is easier), and he is applying only 2/3 of his weight - I think I'm being conservative here - to the outside peg in a 45 degree angle turn, and the peg is 10" from bike centerline, that gives us t=10*120*.707 = 848.5 in-lbs (70 ft-lbs) of torque on that motorcycle frame. With 250cc bikes going around 350-400lbs wet, that torque is almost 20% of the weight (remember most of the rider doesn't count because he's causing the moment.) That is not insignificant. There's definitely SOMETHING happening there.
When a rider is "hanging off" - are they actually hanging their weight? If so, on what part of the bike? One poster wrote that the pros shift their weight 20 times in a turn - while 'hanging off.' That's a lot of shifting. In TOTW2, Keith was using the outside peg as his "pivot point" - where his weight was focused. I'll bet money he was 'hanging off' as well, but keeping his weight pushed to his outside foot - no small physical task. And that he was on a 250cc bike tells me there wasn't a lot of relative bike mass for him to overcome - yes there were centripetal and centrifugal forces from the wheels, but when he applied his weight to the outside peg, it definitely mattered to the bike.
The other significant point made in TOTW2 is that when pressing on that outside (or inside peg) the bike "feels" your body mass MUCH nearer its own CM and that makes the bike happy and stable, regardless of the angle. Adventure guys and Trials guys stand on their pegs - why? It lowers the perceived CM for the bike and is more stable. When we 'flick' our bikes over, we WANT instant instability, followed by complete stability while in the turn...make one good steering input, hold it there with your "criss-cross-torso-pressure-system," and you get to enjoy the turn.
So, in summary...
Yes the advantages outweigh the disadvantages, and it actually makes mathematical sense, so yes, Coach Cobie, it DOES matter. Thanks for reading. I'm looking forward to May at Baker Motorsports.