Ignoring the people who are only here to piss on tattoos (and I'm kind of surprised there's so many of them), I gotta say that a full sleeve as a cyclist should be fine. You will probably tear it up a little if you go down, but I've seen some heal nicely. Will give the art more character, right? If you're really worried about it you could ride with a full sleeve jersey or those arm covers. That way the extra layer tears before the skin does. Course, then no one can see your sleeve while you're riding and, being a "shortsighted" and "pathetic" owner of a few tattoos myself, I know that's part of the fun of having one...or several...or several dozen. So either don't go down, don't worry about it too much, or cover it to be extra safe.
On a personal note, I'd love for some of you people to come on out to Hawaii and let these people know how you feel about their tattoos. Or if its a cultural thing is it ok? A whole bunch of them have it, seems kind of "herd"-ish to me. While you're here come to the school I teach at and tell my students what they should think of me and the other teachers who have visible ink. After you leave I'll go back to my lesson on treating everyone equally and not judging a book by its cover. The next lesson will be about painting a group with one brush (i.e. tattoos = Jiffy Lube guy = ignorant and never amounting to anything) and how that makes you look. You could stick around for it if you want.