Thanks To Jehu on ADV rider who wrote in his post:
This Bultaco sold for $20K a few days ago on eBay.
1971 Bultaco Metralla MK2 owned by Kenny Roberts. The story on this bike is Senior Bulto and the Barcelona Bultaco Club gave Kenny Roberts this bike as a gift at the 1994 Barcelona GP. This bike is new not restored. Kenny is trying to locate the picture of Senior Bulto giving him this bike. If he can find it the picture it will be included with the bike. Also included is a letter from Kenny stating the authenticity of this bike. The bike runs but the petcocks leak so they will need to be repaired. The frame and engine numbers match. Bike shows 76 km = 45 miles.