I think you are getting some terminology mixed up here. A slipper clutch and an automatic (centrifugal) clutch are two very different things. A slipper clutch is typically for street and road racing applications where aggressive engine breaking is not wanted. Right from Rekluse's FAQ:
And while we're at it, saying "Rekluse" doesn't necessarily mean auto clutch. Rekluse is the name of a manufacturer that makes both auto and manual aftermarket clutches. And the Rekluse auto clutches are unique in that they use a clutch disc and plate pack type clutch and still get centrifugal clutch actuation, which is different from a centrifugal clutch in a Honda utility atv which uses a drum and weight set.
Now on to your more specific questions.... No, just cause you can start and stop and shift your 420AT without a clutch lever does not mean you have a Rekluse type clutch in it. What you have are 3 clutches actually. The first is the automatic centrifugal clutch, which is the drum and weight type and allows you to idle while in gear without moving, and start out nice and evenly. And then your 420AT has 2 clutch pack type clutches that allow enough slip for gear changes to occur, and which one is engaged determines which subset of gears in the DCT are being used to transfer power. The built in computer controls that and gives you the option to either use ESP like you said you do, or auto mode.
Now a footshift or regular ES honda utility atv has just one of those shift clutches, and is provides slip when the shift shaft is engaged.
Still tracking?
Now on to honda dirt bikes.... Most of the ones 100cc on the up are all manual clutch. But some of the smaller ones have both an automatic centrifugal clutch and shift clutch setup like the footshift utility ATV's. These are typically kids starter bikes.
But if you have a bigger dirt bike that you want to have automatic clutch actuation, that is where a Rekluse auto clutch can come in.
