MotoGP chassis engineers and other students of vehicle dynamics know there are more complex variables at play: the weight of the vehicle, the length of the wheelbase and the amount of steering offset, for starters. But reduced to simplest form, a chopper's relatively radical rake and longer trail make it harder to balance as well as harder to turn, particularly at slow speeds. Both variables are interrelated and inseparable, but trail is more influential when it comes to steering feel. Other variables being equal, bikes with less trail feel agile and responsive, while those with more trail require greater effort to deviate from a straight line. That's great for a relaxing troll down the interstate, but not so good for playing shopping-cart slalom in the Costco parking lot on Saturday morning.