XR50 Motard:
http://www.honda.co.jp/motor-lineup/xr50-motard/
XR100 Motard:
http://www.honda.co.jp/motor-lineup/xr100-motard/
Not available in the USA, but if Honda did release these as street legal bikes, they would be popular here. 1000's of aftermarket parts available for them and have changed the face of motard racing in Japan at the Suzuka Circuit.