When Honda redesigned the XR200R in 1986, it basically acknowledged that the '84/'85 four-valve machines were a mistake. Honda redesigned the '85 frame to accept the much smaller, simpler and lighter 1983 and earlier two-valve engine. The combination worked, and thousands of riders got to experience a real trail four-stroke. The two-valve engine isn't a powerhouse, but every pony of the horsepower is domesticated, so all of the modest power output gets to the ground. Coupled with a six-speed gearbox, the little bike is very capable and was one of the best options for learning riders, women and others who were vertically challenged. The bike was slim and easy to work on, as well. A 17-inch wheel on the rear is a bit of a problem as that limits tire choices; IRC has some of the best meats. The drum brakes don't have the feel of modern discs but work just fine. Unlike later models, the shock is adjustable and rebuildable. Lights came stock through 1988. There were no 1989 or 1992 models. In 1993 the linkage and suspension changed to shorter travel as Honda no longer considered the bike a viable competition model, so the seat height was claimed at only an inch taller than the current CRF100F. From 1993 to 2002 the bikes were unchanged except for graphic and color treatments.
Buyer Beware
These were bikes that appealed to people who didn't want to work on them. Since they often ended up in the hands of the uncaring or unlearned, many are thrashed. If the engine is allowing smoke out the exhaust pipe, the engine is tired. A rebuild is cheap, though, and the cranks aren't usually an issue.
The kickstart system requires adjustment (shown clearly in the manual), and when adjusted, the XR is one of the easiest four-strokes to kickstart. If the kickstart ratchet starts to slip, and they do, be ready for a time-consuming rebuild since the cases need to be split.
Watch out for bikes that don't shift properly. Crashing on the shifter will cause shift shaft and shift fork problems.
If the rod-operated rear drum brake is adjusted too tight, the brake will drag when the suspension compresses.
Commonsense Mods
Make sure the engine is mechanically tight, and that there aren't a lot of performance parts installed. That indicates the bike wasn't used as intended.
The engine doesn't need a loud pipe, so look for a quiet one. If you have the stock muffler still, the insert from an ATC200X offers a good sound/power compromise.
Uni Filter makes a larger filter and cage for dusty areas.
The '86 to '91 suspension internals are vastly superior to '93 and later short-travel models, and the shock can actually be rebuilt, but the components are still rudimentary inside. The fork is so small that there isn't a lot you can do. Fortunately, the suspension is fine for trail use. The front end from an '84/'85 XR250R is a direct bolt-on, and it has larger tubes and a front disc brake. Most of those XR250Rs are blown up basket cases now, so it is possible to find them. Later short-travel models will take the '84/'85 or '86 to '91 shock and fork, but you need the linkage, too, and the front wheel and brake from the 250.
For models without lights, Baja Designs and others can set you up with lights and the ignition mods to power them pretty easily.
Target Rider
The XR200R is a simple and reliable trailbike that is great for short or learning riders, but one that is limited in power output and more limited in suspension. But it is cheap, easy to start and lighter than current e-start units that have replaced it. It isn't a great bike for hop-up potential, but for gnarly, low-traction riding it works great. If you can find a clean one, grab it.