AlexCyclistRoch

I've been using Simple Green mixed 4:1 with water for chain cleaning lately. Works really well, but you gotta rinse the **** out of it afterwards and dry the chain.

Carbonfiberboy 

The side plates help a lot plus the rollers are full of lube when the chain comes from the factory. Leave it there. The lube keeps the dirt out. You may notice that there's not much play in a new chain. The pins and rollers fit tightly together. Thus it's important not to wash the lube out because it's really hard to get back in again, for the same reason that dirt and water don't get in when they're full of lube.

I ride in the rain and grit a lot here, and my chain life almost doubled when I quit using a brush box filled with paint thinner to clean my chain. In winter, we mostly ride our tandem and tandems are really hard on drive chains. Ordinary washing with soap and water doesn't seem to bother the chain. In fact, it's important to wash or at least wipe the grit off the cogs and rollers because that grit is what wears your chainrings and cassette.

It it's not too filthy, I just wipe the chain clean with a rag or paper towel, warm and dry it with a shrink tube attachment on a heat gun while pedaling, apply chain lube and warm it in again while pedaling. I use Finish Line Ceramic Wet lube. Takes 5 minutes.

I've been riding in the rain in the PNW for 20 years and have a pretty good idea of what works and what doesn't.

Carbonfiberboy 

My experience is obviously different from yours. Perhaps I ride in a harsher environment? I've been experimenting with this through 20 years of all-winter rain riding.

I don't see how I would clean 1/4" of road grime off my frame, wheels, and drivetrain without soap and water. I wash my car, why not my bike? If you've ever ridden for 5 hours in a downpour, I can't see how you'd worry about a little water from a hose. Cyclists here even use car-top racks! 65 mph in the rain doesn't seem to bother a bike either. It's just a matter of having good equipment and taking care of it. My 2003 CK tandem hubs have never had the bearings replaced. My single BBs last ~25,000 miles. Our tandem BB bearings only last ~10,000. I don't think this is unusual.

My bikes don't usually need a wash after a real rain ride. It's wet roads and little rain that get 'em filthy. I don't think soap hurts bike paint, either. I use Pedro's Bike Lust after a wash. Makes even old paint nice and shiny again.