IN BRIEF : Tyson Weighs In at 218, Bruno 228

Mike Tyson weighed in at 218 pounds today for his heavyweight championship defense Saturday night against Frank Bruno of Britain, who weighed 228. Tyson weighed 2 1/4 pounds less than when he knocked out Michael Spinks in 91 seconds last June 27. Bruno weighed 228 when he was knocked out in the 11th round by Tim Witherspoon in a bid for the World Boxing Assn. title July 19, 1986. (Earlier story, Part III, Page 1.)