Ford questions feelers to CubaSAN FRANCISCO (AP) —Former President Gerald R. Ford said Tuesday he has grave reservations” about President Carter's hints of better relations with Cuba.“There are Cuban troops still in Angola,0 Ford said in his brief comment while walking to a luncheon. He did not elaborate and news reporters had no further access to Ford.While president, Ford had cited the Angolan civil war and Cuba's alleged participation in it as a deterrent to improved relations between the United States and Cuba.The former president was in San Francisco to speak to 20 fellows of the Eisenhower Exchange Fellowships. Ford recently assumed the largely ceremonial position of president of the fellowships.