* Continues to see 2017 shipments to be flat to down modestly
* Q1 shipments 70,831 units vs forecast 66,000-71,000
* Shares down 4 pct (Adds background)
April 18 (Reuters) - U.S. motorcycle maker Harley-Davidson Inc kept its 2017 outlook unchanged despite first-quarter shipments hitting the high end of the company's forecast.
Milwaukee-based Harley's shares were down 4 percent at $57.00 in premarket trading on Tuesday.
The company, which commands about half the U.S. big-bike market, said motorcycle shipments fell 14.7 percent to 70,831 units in the quarter ended March 26, compared with its forecast of 66,000-71,000 units.
Harley said it continues to expect full-year shipments to be flat to down modestly.
Harley's first quarter shipments were helped by warmer-than-usual weather that led to an early start to the annual riding season, probably resulting in a pull-forward in demand from the second quarter, analysts have said.
Harley also took the rare step of offering rebates on its 2016 motorcycles to U.S. dealers as an incentive for them to shift a backlog that had restricted sales of its latest models.
Demand for Harley's motorcycles continues to be slow as its loyal baby boomer demographic ages and rivals such as the Indian brand bike maker Polaris Industries Inc and Japan's Honda Motor Co Ltd offer competitive discounts.
Revenue per motorcycle fell about $342 to $$15,526 in the first quarter, Harley said.
The company's net income fell 25.6 percent to $186.37 million, $1.05 per share, in the quarter, from a year earlier.
Revenue from motorcycles and related products fell 15.7 percent to $1.33 billion.
Analysts on average had expected earnings of $1.02 per share, according to Thomson Reuters I/B/E/S. (Reporting by Rachit Vats in Bengaluru; Editing by Maju Samuel)