I ride the sand dunes and my friend has a Z400 Suzuki and he slides around in the sand really well. I was wondering if I put a wider back axle on it if it would help me slide better?

 

Raptors are taller, narrower and have more weight distributed to the rear wheels. By widening with axle and a-arms, and installing a longer swingarm you will drastically improve your ability to slide. Deep pockets will be necessary if you can't live with it.

 

yes a wider axle

 

Tire choice will also play a part in how well you slide. A shorter wider front tire will slide better than a taller narrow one. For the rear v-paddle designs will slide more controllably than a straight paddle. Reason being is they move sand at a more consistant rate, although less of it thats why straight paddles hook-up better. I had Sand Skate II's on my raptor for awhile and they were killer for high speed slides and whipping the rear end around. I've got 20x10x10 Hauler Extreme 9 paddles now and they get alot more traction than the skates and I can still whip the tail end around but they don't slide as good. The wider axle will help too because the wider you are the harder you can push the bike before it rolls. Large offset wheels, wheel spacers, or wider axle will all help. Just gotta decide how much you wanna spend.