I wave to all bikes. Sometimes they wave back sometimes they don't. Some just nod. A nod is as good as a wave. Sometime you can't wave ie shifting, etc
here an article I found a while back
The Joy of Motorcycle Riding
I love motorcycles, and I love riding. Like many of you what first drew me to bikes was not just the experience of riding, but the feeling that I'd become part of a special community - a brotherhood, really. Nothing calms me more than a long ride down the interstate, waving to the members of my beloved clan. Except when I pass Harley guys. I hate Harley guys. Hate, hate, hate. When they pass me on the highway, you know what I do? I don't wave. With their little tassel handlebars and the studded luggage and the half helmets - God, they drive me crazy.
You know who else I hate? BMW guys. Oh, do I hate those guys. I don't wave at them either. They think they're so great, sitting all upright, with their 180 degree German engines. God, I hate them. They're almost as bad as those old bastards on their touring motorcycles. You know what I call those bikes? "Two wheeled couches!" Get it? Because they're so big. They drive around like they have got all day. Appreciate the scenery somewhere else, Grandpa, and while your at it, I'm not waving to you.
Ducati guys - I don't wave at them either. Why they don't spend a little more money on their bikes? "You can have it in any color as long as it is red." Aren't you cool! Like they even know what a Desmo-whatever engine is, anyway. Try finding the battery, you Italian-wannabe racers! I never, ever wave at those guys.
Suzuki guys aren't much better, which is why I never wave at them, either. They always have those stupid helmets sitting on the top of their stupid heads, and God forbid they should ever wear any safety gear. They make me so mad. Sometimes they'll speed by and look over
at me and you know what I do? I don't wave I just keep going. Please, don't get me started on Kawasaki guys. Ninjas? What are you, twelve years old? Team Green my ass. I never wave at Kawasaki guys.
I ride a Honda, and I'll only wave at Honda guys, but even then, I'll never wave at a guy in full leathers. Never, never, never. Yeah like you're going to get your knee down on the New York Thruway. Nice crotch, by the way. Guys in full leathers will never get a wave from
me, and by the way, neither will the guys in two piece leathers. And I'll tell you who else I'm not waving at - those guys with the helmets with loud paint jobs. Four pounds of paint on a two pound helmet - like I'm going to wave back at that! I'll also never wave at someone with a mirrored visor. Or helmet stickers. Or racing gloves. Or hiking boots.
To me, motorcycling is like a family, a close knit brotherhood of people who ride Hondas, wear jeans and a leather jacket (not Vanson) with regular gloves and a solid color helmet with a clear visor, no stickers, no racing gloves and regular boots (not Timberlands). And isn't that what really makes riding so special.