4Strokes.com Honda Articles: Big XR Chronology By Jeff Deeney

Here's a brief chronology of Honda's big XR's (XR500, XR500R, XR600R) from 1978 to 1997:

1978 to 1982:	Honda introduced XR500. Dual shocks on the rear. 7-9" travel on each end. Honda's first pure dirt 4-stroke. Somewhat heavy, but good handling with stiffer springs. Drum brakes at both ends. Odd 23" front wheel for the first couple of years.
1983 to 1984:	Single shock rear suspension. Front disk brake. Approx 11" travel both ends. Dual carb setup. I owned a 1983 for about 6 years and really liked it. A little heavy, but stiffer fork springs made it a nice handling bike.
1985 to1987:	Displacement increased to 600cc. Little else changed. Bigger displacement added quite a bit more torque. '85/'86 models had some problems with 3rd gear breakage.
1988 to 1990:	Nickasil cylinder, single carb, and stainless steel exhaust. Weight decreased about 10 pounds over the '87. Rear wheel changed from 17" to 18". The decompression mechanism was changed from a kick starter actuated system to a cam speed actuated system to prevent the nasty kickback of earlier XR's.
1991:	Cartridge forks and rear disk brake.
1992:	Little or no changes.
1993 to 1997:	Larger diameter front axle.

Credits: Content from Jeremy Hansen