i use turtle wax bug and tar in the spray bottle,
http://www.autobarn.net/t-520.html?site=google_base
just used it to take off week old bugs this AM

 

I use the Harley Davidson bug cleaner spray. Works pretty good and doesnt hurt paint or chrome

 

warm water

 

Warm soapy water, or awet towel laid on the windscreen, approved bug cleaner for bikes. Becareful about using windex or ammonia based cleaners on your clear plastics.

 

Baby butt wipes, the really wet kind, you'll be surprised.

 

For hard to get into places? I use a wet dryer sheet on any accessible place but I would think a 50/50 mix of fabric softener and water would work on those hard to reach spots.

 

I keep a 1 gallon herbicide sprayer with a 50/50 mix of Simple Green and water. If it is really bad, I just spray it every 5 or 10 minutes for a half hour or more. Usually comes off pretty easy after that.

 

Pledge furniture polish. NOT the universal do-it-all crap either; just the spray or Pledge wipes (which I carry all the time) then any clean "microfiber" cloth to finish up...I know first hand lots of Gold Wing (A large Japanese touring bike with a windhield the size of a table top) guys who use nothing but and I used it back in the last century when we wore face shields that snapped onto the front of what are now called "3/4" helmets.....the re-sealing bags of wipes are tops.....fills in micro scratches and aids in rain repelling, too.