You guys are actually both right but about different things. Slow-speed turning which doesn't generate lateral-acceleration forces (and you stay upright) is completely different from high-speed turns with leaning.

At high-speeds, there's two states in steering & turning. The first is the turn-in where you go from 0-degrees lean to whatever angle carves the radius you want. Then the 2nd stage is steady-state cornering where the lean is steady and the radius is fixed. Coming out of the corner is the reverse of the turn-in where you go from maximum lean-angle back up to 0-degrees.


Here, try this experiment...

1. find an empty parking lot where you can ride in a straight line for 10-15 seconds @ 10mph+ uninterrupted
2. start down the parking lot and take your left hand off the hoods
3. steady yourself so that you can ride with just your right hand on the right brake-hood in a straight line
4. push forward with your right hand and note the direction the bike leans and turns
5. repeat the experiment again with just your right hand on the brake-hood and.
6. pull back with your right hand and note the direction the bike leans and turns

Try this out on a motorcycle at 50mph+ and push/pull on the bars with just one hand and this experiment will really make sense (because the forces required to make it lean and turn is a lot higher, making the direction of the forces obvious).


Then, fill in the following form:

4. pushing forward with your right hand turns the wheel ___________ and the bike turns __________.


6. pulling back with your right hand turns the wheel ___________ and the bike turn __________.