Shares of Harley-Davidson Inc. /zigman2/quotes/207565294/composite HOG -0.68% tumbled 6.6% in premarket trading Tuesday, after the motorcycle maker reported a surprise fourth-quarter loss, as motorcycle revenue fell more than forecast. The company swung to a net loss of $96 million, or 63 cents a share, from net income of $13 million, or 9 cents a share, in the year-ago period. Excluding nonrecurring items, the company swung to an adjusted per-share loss of 44 cents from a profit of 20 cents, compared with the FactSet consensus for earnings per share of 21 cents. The company attributes the loss to weakness in the motorcycle and related products segment, which offset earnings from financial services. Revenue dropped 32% to $725 million, topping the FactSet consensus of $723 million, as motorcycle revenue fell 39% to $531 million to miss expectations of $590 million. Motorcycle gross margin fell to 21.6% from 25.2%. The stock has rallied 21.5% over the past three months through Monday, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.41% has gained 14.0%.