The Honda NSR250R is a street-legal road-orientated 249cc two stroke sport bike produced by Honda Motor Co., Ltd between 1987 and 1999. It evolved from the popular NS250R MC11 and was produced over four distinct generations, each powered by liquid-cooled, reed valve inducted 249cc 90° V-twin two stroke engines. All engines incorporated the Honda RC-Valve power valve system, and nikasil-sulfur lined cylinder bores (hence the 'NS' in 'NSR'). The road going NSRs were built in the image of the Honda RS250R (also known as the NSR250) production race motorcycle series, although they shared no mechanical parts. This was in the style of competing factories Yamaha and Aprilia.

MC16

1987 NSR250R MC16 1987 Ignition System: CDI 1987 Swing-Arm: Straight with Rear Brake Lug

MC18

1988 NSR250R MC18 R2j 1988 NSR250R SP R4j Rothmans MC18 1988 Ignition System: PGM-I 1988 Swing-Arm: Straight with Rear Brake Lug 1989 NSR250R MC18 R5k 1989 NSR250R SP MC18 R6k 1989 Ignition System: PGM-II 1989 Swing-Arm: Straight (Rear Brake Arm used, so no lug)

Engine/Gearbox

MC18 R5k

The engine is a 249cc 90° V-twin liquid-cooled two-stroke with crankcase reed valve induction via twin naturally aspirated carburetors. Bore and Stroke: 54mm × 54.5mm The gearbox is a six-speed constant mesh cassette type with multi-plate wet clutch.

MC18 R6k

The engine is the same as the R5k. The only difference is that it has a dry multi-plate clutch.

Suspension

MC18 R5k

Front: Twin telescopic forks. Oil-filled damper with spring preload adjustment only. Rear: Single rising rate shock. Pro-Link with external coil. Variable spring preload adjustment only.

MC18 R6k

Front: Twin telescopic forks. Oil-filled damper cartridge with spring preload and rebound damping adjustment. Rear: Single rising rate rear shock. Pro-Link with external coil. Gas/oil damper with variable spring preload. Rebound and compression damping adjustment.

MC21

1990 NSR250R MC21 1990 NSR250R SP MC21 1991 NSR250R MC21 1991 NSR250SE MC21 1992 NSR250R MC21 1992 NSR250R SP MC21 1992 NSR250SP Rothmans MC21 1993 NSR250SE MC21 1991-93 Ignition System: PGM-III 1991-93 Swing Arm: "Gull Arm" Right side curved to accommodate exhaust pipes

MC28

1994 NSR250R MC28 1994 NSR250R SP Rothmans 1994 NSR250SE MC28 1995 NSR250R SP HRC 1996 NSR250R SP Repsol 1996 NSR250SE MC28 1994-96 Ignition System: PGM-IV 1994-96 Swing-Arm: "Pro-Arm" single sided.