Do you want to actually get your bike clean, or not?
I ask this because people do all this namby-pamby bike washing with really mild soap and what not. It's earth-friendly this and green that according to the marketing... But most of that stuff doesn't really get a bike clean if you've really, really mucked it up.
Matter of fact, I don't try to keep my bikes really clean. I do keep the moving parts as clean as I can keep them - I clean the drive train, try to keep the cables clean, especially where they go into a housing, try to keep dirt out of the bottom bracket bearings... but other than that I could give a crap. The moving parts that wear out, the metal-on-metal bits especially, you need to keep clean. The rest of it doesn't matter.
Cleaning those moving parts is tough though. They're always mucked up with lube, and lube attracts dirt, and dirt attracts water, which then makes cement. It should be a song how that happens, actually.
I've tried a range of stuff. Orange Zep, the citrus cleaner you can get from Home Depot, is pretty good for removing greasy gunk. (Lube, dirt, sweat + lube + dirt). Simple Green works pretty good too but I wouldn't leave metal soaking in it longer than 10 minutes; it has been known to eat the metal plating off chains.
Yeah, I guess these are better than old school kerosene. But don't kid yourselves about these being earth friendly. A few weeks back I washed a bike after a ride. I had some heavily diluted Simple Green or Zep in some warm water in a bucket. I left the bucket outside because I was going to need it the next day after that ride, since there was rain in the forecast. That night, I go to walk the dog and spot a dead bird in the bucket. I made a mental note to myself: empty the bucket as soon as you've washed the bike post-ride tomorrow AM. So when I get home from the ride, there's a *second* dead bird in the bucket of heavily diluted Simple Green.
Okay, what this shows, other than the fact I'm a callous bastard, is that supposedly earth-friendly stuff is frickin' deadly. Don't kid yourself that it's not. You should use as little of it as possible. You really think that bird-killing stuff ought to be released into nature? If it kills birds, it isn't good. Well, unless it's a shotgun and you're hunting birds, but that's totally different.
The second thing is that if you really need to de-gunk something, you might want to consider going with some heavy-hitting solvent, and make sure you dispose of it as properly as possible.
For light cleanings, I do stick with the Simple Green or Zep. A little in a bucket of warm water to help degrease the bike, and some sprayed generously on the drivetrain to get the gunk out. I know it's not entirely sound to do this because it removes the lub embedded in the chain bushings, but my chains last 2000-3000 miles at the best of times before I snap them or stretch them into something resembling liquorice taffy, and I lube a couple times a week, so I don't worry about it. Let the drivetrain soak for 5-10 minutes, and then scrub the rest of the bike with the warm water. Hose off (yeah, killing more birds there) and hose off the drivetrain carefully. Do not spray high pressure water into your hubs or bottom bracket! That would be stupid! (This means, naturally, that I've done it). I throw the bucket's contents down the laundry tub, from whence they journey to the sewage treatment plant which (we hope) filters out common household cleaners or at least breaks them down. I know, I know - I'm killing crabs, and not just by eating them by the dozen. It's almost enough to make a man give up riding and take up driving an Escalade, just to be nicer to mother earth.
A key tool to help with scrubbing down the bike is a set of Pedro's Bike Brushes. They are awesome, and a kit of 5, which includes brushes to get into all the relevant little nooks and crannies, runs around $20. A *great* investment. I am pretty sure that all their tools, like this, are made from recycled stuff, so it almost makes up for being the Jack the Ripper of the Avifaunal kingdom.
Okay, now here's the deep, dark, dirty secret for those of you not already repulsed by my sickening fixation on dead birds. (That gets worse too: I've been known to eat turkey, duck, chicken, grouse, quail, and whatever it is they make McNuggets out of).
The secret is that if you really need to get grit out of your drivetrain and you don't have a week to soak the stuff, any good degreaser in a spray can, or carbereutor cleaner (like Gumout or STP) will do a bangup job. Take off the chain (easy peasy if you're rocking SRAM with the PowerLink), take off the casette, put them in a coffee can, and spray generously.
Why a coffee can? Because you're using wicked hazardous solvents. You don't want to use a lot of them, or just spray them out in the road under your bike. Birds could pay the ultimate price for your shiny Campy 11 gruppo, right? So if you do the washing in the coffee can, you can hang on to the solvent (you cap the can) from month to month, and then dispose of it properly. Your local gas station / service center may take it, and if they don't the county landfill should have a hazardous waste station for you to use.
Anyhow, once you spray off the drivetrain components, let them soak for a few minutes, then use an old toothbrush to clean the muck off. The only stuff that will be left after the initial spray is seriously hardened goop; the spray alone will get the chain and rings cleaner than Simple Green plus scrubbing. Dry with a shop rag, and they will be shiny and new looking. Not so, your fingers, but this post is about cleaning your bike, not your hands. To clean the chainrings, just take that solvent-soaked shop rag, and go to town. It will only take a minute or two to get the grit out of that. Then make sure you lube up properly; you've just stripped out all the reachable lube from that chain.
So there you go. That's how I show my bike some love. If you show the bike love, it will love you back. As for the birds... I dunno. Lately a couple hundred of them have taken to nesting in a tree out behind my house. I'm thinking they're pissed about something. I believe that I'm going to go hit up KFC for some chicken, watch some basketball, and think about it.