Re: How to get flys off the bonnet/front of car...
Here in DK we have a foam-spray called "Insect-Remover." I think it's from BASTA...but not sure. It works ok. If your local car detailer or store don't carry this, just try some gentle solvent or plain car shampoo. Let it sit for 5-10 minutes and soften the bugs before going over it again. You need something that dissolves biological waste.
Re: How to get flys off the bonnet/front of car...
There is a product called Rejex that I and many otheres can say REALLY works, after my cross country drive the Bugs juice just washed off! Previously it was hours with bug & tar remover