I think that you have already identified a major hazard: Old paving bricks do get slick when wet. The most slick time is when a rain first starts especially if it just wets the streets and does not supply enough water to flush the surface. Acumlated grime, tire wear particles and oil drippings,are present and very slick when wetted. If you see the shimer of an oil film, assume it is as slick as greae and avoid it if possible.

On 2 lane roads, watch for puddles in the oncoming lane. If a vehicle comes toward you and you are in the wrong place, expect to get drenched when the approacing vehicle splits the puddle. Worst of all, your vision can be impaired and you can't see where you are going. This is scary.

Brakes: If you have not ridden your bike in the rain before, you do not know how your brakes will react when wetted. Once, I was riding a 750 Honda and was struck by a brief shower. My brakes were gone! The brake pads aquaplanned on the rotors giving very little resistance. I took a side street and dragged the brakes for a half mile before they heated enough to drive away the water and then braking was poor until the brakes had been thorougly heated. That was one bad ride home. The problem was cured by changing to better pads and cleaning the rotors. This one is a sneaky problem and must be fixed if you have it. Its sneaky because it can develop while highway riding at the begining of a rain. You don't know that you have lost your brakes until you need them. So, when riding in the rain, periodically test your brakes.

And of course, you already know that crossing railroad tracks at an angle when wet can be hazardous when especially if the rails are elevated above the road surface.

The not so obvious is paint stipes on the roadway. You are going around a corner a bit fast and leaned over when the front wheel suddently skids as it crosses a paint stripe; The newer the stripe, the worse it is.

Beware that the majority of oil drippings lay in the center of the driving lane. When riding on wet pavement, it is safer to ride in the tire tracks. Use caution when crossing the center part of the lane.

Suppose you are crusing down the highway at 65 mph, you can anticipate where the dips and bumps are. As you look ahead, you notice a pattern in the oil drippings on the roadway. The oil smear on the pavement is greater right at and just beyond dips and potholes. Oil droppings are greater at these disturbances. A new road surface will not show this pattern until it has seen enough traffic. Many road bikes can handle these bumps better than autos owing to differenes in suspension systems. Reading the road pattern ahead gives you advance warning.

jemdandy--thanks for all the valuable information on scooter riding. Sorry it took so long to get back. I'm pretty sure that I will purchase a Kymco for tooling around town. I am still a little nervous at age 71 and wondering if my attention span and poor hearing ought to keep me off the scoot.

If I do it and if I survive it I'll let you know.

Thanks again for your thoughtfulness, time and help.
Mike