1981 - 1982 Honda XR 500
In 1981, Honda retired
the dual rear shocks and introduced the Pro-Link rear suspension on the XR
500. This new design brought with it a host of new frame revisions. The "Ride
Red" folks also changed the front wheel dimensions too. The '81 XR came with
a more conventional 21" inch front wheel, rather than a 23" front wheel. As
for the rear wheel, Honda, for some strange and disturbing reason, fitted
a 17" rear wheel, rather than go with the previous models 18" rear wheel.
(Go figure.) Apparently Honda felt that was enough design gymnastics because
the engine did not receive much in the way of changes.
The '82 XR 500 received cosmetic updates.
1983 - 1984 Honda XR 500
In 1983, Honda struck a stroke of brilliance, and offered a completely new XR 500. The bike's revamped engine was capped by a Radial Four Valve Cylinder head that two carburetors and two exhaust pipes connected to. The XR came with a front disc brake, frame updates, and new, beefier forks that were anything but beefy at high speed. Nontheless, people snatched the up new XR's quickly. The '83 XR 500 breathed new life into the big bore 4-stroke realm for the folks that didn't ride the European 4-strokes.
The XR 500 remained mostly unchanged in 1984.
1985 - 1987 Honda XR 600
Honda, realizing that more cc's meant more power, injected a 100cc dose to the XR 500 engine making the XR 500 an XR 600 in 1985. This made a fairly strong running machine run a bit stronger. Other changes included an aluminum, rather than steel swingarm, a dry sump engine oiling system, and frame changes.
Except for graphics, the XR 600 did not change appreciably until 1988.
1988 - 1991 Honda XR 600
Honda revised the XR 600 in 1988. The design folks at Hamamatsu threw the 2 carburetor sytem into the recycle bin and attached one engine carb instead. Surprising, the Honda people realized the XR needed to be placed on a badly needed diet. So... the XR was put on a diet - and it lightened by 10 pounds. The changes did not end there. The engine received the Nikasil liner treatment and, shockingly enough, the XR 600 came with an 18" rear wheel!
Blessed with these changes, the only notably big updates the XR 600 received
unitl 1991 were bold new graphics...
...and bold new price increases.
1991 - present Honda XR 600
1991 came, and with it brought cartridge forks, that were nearly identical to the 1987 CR 500 forks, and a rear disc brake to the XR 600. Apparently these updates were fairly advanced, because Honda has not changed the XR 600 much since.
Except for the bold new graphics and prices!