It really depends on what you're looking for. I personally just bought a '02 R1 and already ordered a seat cowl and a smoked windshield from Yamaha. I also ordered a fender eliminator from gravesport.com and I'm contemplating a K&N filter and a velocity stack kit. Modifications are pretty much endless on a bike, as on anything else. It really depends on what you are looking for; looks, increased performance, etc. which will direct you in your modding quest.