Honda XR 250R

Dirt Bike Rider review 1986

Last month Dirt Bike tested the new XR250 and came away favorably impressed. The Honda engineers set out to make a potent Eastern enduro machine that was competitive in stock form. And for the most part, they accomplished that goal. The machine is lightweight, has a semi-healthy power output, and handles better than most four-strokes have ever dreamed of handling. However, during the course of the test, we became familiar with some glaring faults that kept creeping up—a rear shock rebound factor of zero, fork action that was too mushy, and a motor (although semi-brisk for a four-stroke) that could use a bit more juice.

WHITE BROS., PART I
The three factors that fell short of our expectations—the motor, forks, and shock —weren't hopeless design flaws requiring major surgery to correct. We felt confident that a savvy aftermarket firm could remedy the situation with a low-bucks approach. Dan White of White Bros, fame confirmed our thoughts. Dan told us that he knew some tricks that would instantly enhance the XR, and he agreed to perform them // we would allow him to do a Stage Two XR, which would permit him to go full-tilt gonzo on the bike. Dan was so adamant about this Stage One and Stage Two bit, we had no choice but to agree. This month we will concentrate on Stage One, which consists of a low-bucks fix-it program covering the forks, motor and shock.
According to Dan, the best results he had in squeezing more juice out of the stock mill were obtained by performing a combination of tricks resulting in a full two-horsepower increase on the dyno.

THREE EASY STEPS TO MORE POWER

The first modification on the White Bros, agenda was to install the White Bros, meg-alloy silencer kit with a SuperTrapp spark arrester. This isn't a full exhaust system, but a reverse-cone megaphone silencer. Having completed the pipe mods, they turned their attention to the airbox. A K&N air filter replaced the stock Honda unit. The K&N has no backfire screen like the stocker, and it has a thicker foam material. Five one-inch holes were drilled in the top of the airbox to assist in the breathing department. The final modification was to raise the needle jet one clip. Dan told us that they experimented with 32mm and 34mm carbs, but the results weren't sufficient to warrant the price. Therefore, the stock carb is used with the new setting. By performing these three mods, a full two horsepower is gained on the dyno. That's a substantial increase when you consider that no cam, boring, or porting work has been performed.

FORK IT OVER

With the low-bucks engine tricks complete, Dan turned his attention to the forks. For serious trail work, stiffer front boingers are a must. Dan installed a set of 22-pound ATK fork springs with White Power ten-weight fork oil. Along with the ATK springs, he sent a set of Progressive springs for us to evaluate. These springs, rated from 18 to 22 pounds, are designed to allow a softer ride in the first portion of the stroke and then to progressively stiffen. For the Western or desert rider, the staff felt that the 22-pound ATK springs did the trick, and the Progressive units fit the bill for the serious Eastern enduro rider.

GET OUT THE BACK,

JACK The stock rear suspension of the XR is the weakest link in our test bike. In stock form the non-rebounding qualities of the shock border on the dangerous side in highspeed situations. Progressive Suspension parts helped cure the backyard dilemma. First, the stock spring (with a rating of 505 pounds) was replaced by the Progressive Suspension spring (with a rating of 620 pounds). Then the rebound damping problem was solved by welding and remachin-ing the shock to obtain the needed gain in rebound damping. The results of this modification are significant. The "ride 'em, Bronco" effect vanished, and a controlled, well-mannered rear suspension took its place.

END RESULT

Riding our reworked XR proved to be an enjoyable experience. The motor responded with a shade more fire. Although it's still no missile, it now has the additional grunt to keep the pilot chugging along happily, and with the simple addition of the silencer package and airbox tricks, there should be no more reliability problems.

The response of the heavy-duty fork springs was just what the doctor ordered. The fear of attacking obstacles with the stock forks was replaced by a carefree attitude that let the rider push the XR to its limit. Once again, the biggest single improvement (in our opinion) was the rear shock action. This modification moved the XR from the fun-bike category to the serious-trail-machine category.