Stud bulls where? European Bulls are usually smaller than those here in the States. Of course Euro Bulls only have to run off Fencehoppers, not Bears, Wolves or Stupid Cougars. EXCEPT for mustang stallions, which will go about 800 pounds in a good season, riding horses tend to be over a thousand pounds. That isnt a fat horse, either. A kilo, is 2.2lbs. chum, and that aint changing anytime soon.