it's more that paying attention...it's being fully conscious of your environment and being able to react and make split second decisions without even thinking about it...it's knowing what you and your bike are fully capable of and applying that knowledge to every second of your ride to get the most out of it...it's when riding becomes not just an activity but an instinct...
it's being in the zone...
you know you've reached zen when you feel invincible and you can ride as fast as you want because you know wholeheartedly that you can handle anything the road throws at you...
the line between zen and just riding like a reckless jackass is skill...