Riding in Weather Conditions
Only a freak motorcycle rider enjoys riding in foul weather, but that doesn't mean you'll never do it. Rain, ice and snow can all be surprises so you want to know how to handle riding in poor weather.
Rain poses two major challenges: traction and vision. Traction seems to be the primary concern for most riders. Watch out for metal fixtures (such as manhole covers and bridge gratings), painted areas, and places where built-up oil and grease have not washed off; these become much slipperier when wet. However, there is still a surprising amount of traction on clean asphalt or concrete.
You can test traction by testing a surface with your rear break. (Before you do this: make sure your tires are in good shape; you need a reasonable amount of tread depth). If you do this at moderate speeds on a flat, straight road, it won't become a thrill ride. Avoid locking up the rear wheel on a steeply crowned road, where it will tend to slide downhill and out of line.
Once you have a feel for traction, you should have some idea of how much you can safely ask the tires to deliver under braking and cornering.
There are additional steps you can take to improve traction. Premium aftermarket tires are virtually certain to give better wet-road grip than original-equipment tires. Additionally, a slight increase in tire pressure will improve wet-weather traction.
Be very careful of any large metal road surfaces or metal sections running parallel to your direction of travel including expansion joints, metal plates and railroad tracks. Painted surfaces can be almost as slippery as metal.
Turning a motorcycle on slick, wet surfaces demands a smooth touch. Braking abruptly or making a sudden steering input could get you into trouble.
Additionally, initiate your turns a bit more gradually. Downshift smoothly, engaging the clutch a bit slower than usual, and avoid abrupt throttle changes. Use a taller gear to reduce the forces reaching the rear tire. Apply the brakes in such a way that the tires are not loaded abruptly. Allow more space to stop or slow down so that you need less. And also make sure that drivers around you have time to react to your moves.
You already know that drivers have trouble seeing you. This is an even larger issue in the rain, low light, obscured windows, and a foggy windshield, will additionally impair driver visibility. Consider a bright rain-suit, and retro-reflective striping or panels.
Also consider your own vision. Your view can be impaired by faceshield fogging or a windshield that rises into your line of sight. Rain-X does help disperse water on both face- and, more importantly, windshields.