[5] The SR was styled by Atsushi Ishiyama with Yamaha presenting a pre-production prototype to US dealers in late 1975.

Beginning with model year 2010, the SR400 had fuel injection and a catalyst muffler to comply with tighter emission restrictions.

The air filter is a disposable oil-coated paper type held in place by the airbox cover.

The electrical system has an automatic cut-out to stop the engine when left idling longer than 20 minutes.

[6] A sealed Valve Regulated Lead Acid (VRLA) battery is located underneath the seat, on its side.

[4][7] The SR500 employed a slightly modified version of its large single-cylinder from the XT500/TT500[8][9] and had electronic ignition as well as a handle bar mounted compression release lever to make kick starting much easier.