My WR426 railed in the sand once I stiffened the front and softened up the rear. You really need to stay on the gas and make wider, sweeping turns keeping your speed up. Like others said, don't back off on the throttle and engine brake into the corners since it makes the front end dive and plow. A good front tire also does wonders. I also tend to sit back a little farther and let the front float a little. This also helps you get traction on acceleration. I'd also clean my airfilter everyday when riding in the sand and don't lube the chain with chain lube. Use something more like Triflow or WD40 since sand sticks all over and chews up the drive components.