Here's a link to Sharethedamnroad.com. It's one page, offering for sale half a dozen jerseys, one or more of which may say precisely what you've wanted to say all along.
While Tamar and I lived in Tucson, I yearned for an Often Armed jersey. I was told that such a garment would offer police probable cause to stop me and engage me in roadside chat. I was never sure if that were true.
I am sure I'd have designed an ugly Often Armed jersey. These are pretty good-looking.
I wish I felt more optimistic about a cycling jersey asking drivers to slow down. After all, double fines or threats of imprisonment fail to slow them one mile per hour in highway work zones....