Valves

• The 1984 Honda XR250 motorcycle has a Radial Four Valve Combustion chamber. The RFVC is a design concept unique to Honda motorcycles that, according to the article "Living with Honda's XR250R -- A Decade Gone By," written by Len Nelson, "allows for the use of large valves, better flow and a unique valve actuating method." Ultimately, this design concept increases the life of the valve train.
  
  

Camshaft

• The Honda XR250 valve train features a single overhead camshaft. This means that the camshaft is located above the valves. The OHC configuration allows for a smaller number of valve train components which, in turn, allows for a lighter engine overall.
  
  

Engine

• The OHC RFVC layout of the 1984 Honda XR250 valve train drives a 249 cc single-cylinder engine with dual carburetors. This engine powers a lightweight, versatile and popular dirt bike.