The main objective of all adjustments made for a wet track is to gain as much grip as possible – the rest comes later, or as a consequence. Yet, exactly what you need to do to "get in gear" for the rain depends on whether your kart is gearbox or not. If you drive a shifter, what you want is more wheel drive in order to use all the horsepower you can, so you’ll work mainly on the rear end; if you drive a non-shifter, you’ll be looking to get more overall grip, so set-up changes will be evenly divided between front and rear. Of course, some drivers prefer to keep their set-up unaltered from dry to wet, if they feel it is well-balanced.
In dry conditions, the chassis is usually set as low as the rules allow. When the track gets wet, you need to increase ride height, to shift the overall weight of teh kart higher up off teh ground. In fact, the higher up the center of mass, the more the load tire digs into the ground and so the better corner-through grip. We could state the basic rule as: “when wet, go as high as possible”. You also want to shift the spacers that separate the stub axles from the Cs past the stubs. The other element to work on is body position when driving. Besides, trying to gain bite by shifting his body weight towards the load tire, the driver can add a pillow to his seat to raise his own center of mass and thus contribute to raising the kart's overall center of mass. Of course, it all depends on personal preference. Some people feel uneasy driving with a pillow.
CAMBER & CASTER