Here is a list of available tires (in the U.S.) in sizes 110/70, (120 list is vast) 130/70, 140/70 and for those who dare...150/70. This is not an exhaustive list as there are tires that are made for the Ninja in other parts of the world. Feel free to add to this list if you know of any others.
Avon Front AV55 Storm ST 110/70ZR-17 Blackwall Tire
Avon Storm 2 Ultra (front)110/70ZR17
Michelin Front Pilot Power 110/70ZR-17 Blackwall Tire
Michelin Front Pilot Road 2 110/70ZR-17 Blackwall Tire
Metzeler Front ME Z4 110/70R-17 Blackwall Tire
Metzeler Front Lasertec 110/70V-17Blackwall Tire
Continental Front Conti Road Attack 110/70ZR-17 Blackwall Tire
Continental Front Conti Motion 110/70ZR-17 Blackwall Tire
Continental Front Conti Go 110/70H-17 Blackwall Tire
Continental Front Conti Force 110/70ZR-17 Blackwall Tire
Continental Avenue 110/70 - 17 M/C 54H TL
Dunlop Front Qualifier 110/70ZR-17 Blackwall Tire
Bridgestone Front Battlax BT-014 110/70ZR-17 Blackwall Tire
Bridgestone Front Battlax BT-39 110/70-17 (avail in U.K.)
Bridgestone Front Battlax BT-090 110/70HR-17 Blackwall Tire
Bridgestone Front Battlax BT-016 110/70ZR-17 Blackwall Tire
Bridgestone Battlax 003 110/70ZR17 M/C (54W) TL (avail. in Japan)
Bridgestone Battlax 92 110/70R17 M/C 54H TL (avail. in Japan)
Duro HF918 Sport Bias 110/70H17
Maxxis M6102 Promaxx Front 110/70-17 54H
Maxxis M6029 Supermaxx Front 110/70ZR17
IRC SP-10 110/70R17M/C 54HTL
Pirelli Front Sport Demon 110/70H-17 Blackwall Tire
130/70's Continental Avenue 130/70 - 17 M/C 62H TL
Continental ContiTwist 130/70 - 17 M/C 62H TL
Continental Rear Conti Go 130/70H-17 Blackwall Tire (see these installed:
http://www.newninja.com/news-4/new-rubber-for-my-ride!/msg58227/#msg58227)
Avon Front AV55 Storm ST 130/70VR-17 Blackwall Tire
Avon Rear AM26 Roadrider 130/70V-17 Blackwall Tire
Metzeler Rear Lasertec 130/70H-17 Blackwall Tire
Pirelli Rear Sport Demon 130/70H-17 Blackwall Tire
Bridgestone Rear BT-45 130/70H-17 Blackwall Tire
Bridgestone Exedra G550 130/70H-17 Blackwall Tire
Bridgestone Front Exedra G851 130/70ZR-17 Blackwall Tire
Bridgestone Rear Battlax BT-39 130/70-17 (avail in U.K.)
Bridgestone Rear BT-45 130/70H-17 Blackwall Tire
Bridgestone Exedra G550 130/70H-17 Blackwall Tire
Michelin Rear Pilot Activ 130/70H-17 Blackwall Tire
IRC Rear Road Winner RX-01 130/70H-17 Blackwall Tire
Kenda Rear K671 Cruiser 130/70H-17 Blackwall Tire
Duro HF918 Sport Bias 130/70-17 T/L
Maxxis M6103 Promaxx Rear 130/70-17 62H
140/70's Duro HF918 Sport Bias 140/70H17
Duro Rear HF918 140/70H-17 Blackwall Tire
Dunlop Rear D208SM 140/70HR-17 Blackwall Tire
Dunlop Rear K505 140/70H-17 Blackwall Tire
Pirelli Rear Sport Demon 140/70H-17 Blackwall Tire
Michelin Rear Pilot Activ 140/70H-17 Blackwall Tire
Bridgestone Rear Battlax BT-090 140/70R-17 Blackwall Tire
Bridgestone Rear Battlax BT45H 140/70H-17 Blackwall Tire
Bridgestone Battlax 003 140/70ZR17 M/C (66W) TL (avail. in Japan)
Bridgestone Battlax 92 140/70R17 M/C 66H TL (avail. in Japan)
Bridgestone Battlax 92 140/60R17 M/C 63H TL (avail. in Japan)
Bridgestone Rear Battlax BT-39 140/70-17 (avail in U.K.)
Avon Rear AM26 Roadrider 140/70V-17 Blackwall Tire
IRC Rear Road Winner RX-01 140/70H-17 Blackwall Tire
IRC SP-10 140/70R17M/C 66HTL
Kenda Rear K671 Cruiser 140/70H-17 Blackwall Tire
150/70's Avon Rear AV56 Storm ST 150/70ZR-17 Blackwall Tire
Avon Rear AM26 Roadrider 150/70V-17 Blackwall Tire
Avon Storm 2 Ultra (rear) 150/70ZR17
Metzeler Rear RoadTec Z6 150/70VR-17 Blackwall Tire
Metzeler Rear RoadTec Z6 150/70ZR-17 Blackwall Tire
Metzeler Rear Lasertec 150/70V-17 Blackwall Tire
Michelin Rear Pilot Road 2 150/70ZR-17 Blackwall Tire
Michelin Rear Pilot Road 150/70VR-17 Blackwall Tire
Continental Rear Conti Trail Attack 150/70VR-17 Blackwall Tire
Continental Rear Conti Road Attack 150/70ZR-17 Blackwall Tire
Continental Rear Conti Force 150/70ZR-17 Blackwall Tire
Continental Rear Conti Motion 150/70ZR-17 Blackwall Tire
Dunlop Rear Roadsmart 150/70ZR-17 Blackwall Tire
Dunlop Rear D607 150/70HR-17 Blackwall Tire
Dunlop Rear GT501 150/70VB-17 Blackwall Tire
Bridgestone Rear Battlax BT-021 150/70ZR-17 Blackwall Tire
Bridgestone Rear Battlax BT-021 150/70ZR-17 Blackwall Tire
Bridgestone Rear Battlax BT45V 150/70V-17 Blackwall Tire
Michelin Rear Pilot Activ 150/70V-17 Blackwall Tire
Michelin Rear Pilot Road 150/70ZR-17 Blackwall Tire
Michelin Rear Pilot Activ 150/70H-17 Blackwall Tire
IRC Rear Road Winner RX-01 150/70H-17 Blackwall Tire
Cheng Shin Rear C6000 Barracuda 150/70V-17 Blackwall Tire
Cheng Shin Rear C915 Barracuda 150/70H-17 Blackwall Tire
Maxxis M6103 Promaxx Rear 150/70-17 69H
Maxxis M6029 Supermaxx Rear 150/70ZR17 69W
Kenda Rear K671 Cruiser 150/70H-17 Blackwall Tire
Check the tire manufacturer for rim width recommendations.