It's normal to change your body position in a corner. You want your elbows to be above the plane of your wrists when sitting so you can maintain a strong, comfortable position when sitting during turns or railing a burm. If your bars are too high, it can put you in a weak position forcing you to change how you grip to maintain a strong position adding to the arm pump problem. Forward or back, it's a matter of rider Preference. Personaly, I like the feeling of having lots of cockpit room.