This is from the site Bring a Trailer (https://bringatrailer.com/) ...
This 1987 Yamaha YSR50 is an unmodified minibike from the first year of production with 113 miles from new. Designed to be a scaled-down and street-legal lookalike of period Yamaha racers, the fully-faired pocket bike was produced from 1987 to 1992 and became one of the company’s most popular models in the late 1980s. The bike sparked an active aftermarket following as well as ushering in the careers of numerous young motorcycle racers, and is still commonly used in spec racing. The seller acquired this example from long-term warehouse storage with approximately 100 miles on it, still wearing its original temporary Ohio paper license plate. The bike is said to run well after a carb cleaning, fresh battery, and oil change.
White and silver paint are described as original along with the red 1980s-era race graphic scheme. The Dunlop sponsorship stickers were likely period additions. A variety of chips, scratches and marks on plastic fairings and both full-sized mirrors are said to have been picked up in storage over the years, and are detailed in the photo gallery below.
Minimal trim is largely intact including rectangular side reflectors, though the turn signals are missing despite the presence of a stock signal switch and wiring. A variety of instructional and warning stickers are retained throughout. Stock 12″ wheels wear 3.5″ front and 4″ rear Dunlop rubber that looks to be original, bearing 1986 date codes and still featuring unworn molding fingers.
Up top, a simple instrument panel houses a single 50 mph speedometer with neutral, high beam, signal, and oil level indicators. Grips and controls look fresh, and seat pads appear nearly unworn. Corrosion appears limited to isolated, superficial areas on chassis parts and otherwise bright fasteners.
Power is supplied by the original air-cooled 50cc two-stroke single that made 7.1 horsepower at 8800 rpm when new. The bike was good for a stock top speed of just under 40 mph. After removal from storage, the seller cleaned its single Mikuni carburetor, changed the oil, replaced the original battery, and added fresh gas.
The bike is said to start quickly and run well since the work was performed, and the seller says it rides and shifts as it should with no notable mechanical issues. Shifting is from a 4-up, 1-down 5-speed gearbox. Varnished fluids are visible around the steering tube and other areas of the sportbike-style chassis, while the fuel petcock shows vestiges of red paint.
Documentation is unavailable but the sale includes the Ohio temporary plate the bike was discovered with, as well as its original tool kit and a spare key. A bill of sale will be provided with Connecticut transferable registration, as the state does not require titles for vehicles over 20 years old.
A video of the bike starting has been provided, below.