For this edition of Classic Steel, we are going to take a look back at one of my all-time favorite motorcycles, the 1990 Honda CR125R.
By: Tony Blazier
The ’90 CR125R was a fantastic pro level bike. Stock it pumped out more power than most of the competition’s modified bikes. When you combined that with its unparalleled reputation for durability, it was hard to beat. Photo Credit: Honda
In 1990, Honda was on quite a roll in the 125 class. They had enjoyed a virtual stranglehold on the division since 1986. Some years, the other brands were able to top the CR in one category or another, but most of the time it was hard to beat the little Honda as the total package. Bikes like the ’87 CR125R were so good in fact, that many people still consider it one of Honda’s greatest bikes ever. After several years of dominance, the all-new 1990 Honda CR125R had big shoes to fill.
1990 was the first year that the CR125 received Honda’s complex, but extremely effective Honda Power Port system (HPP). The HPP had been used on the CR250 for several years to provide an extremely broad, easy to use powerband. The addition of the HPP to the 125 gave the little Honda a power advantage that it would not relinquish until the introduction of Yamaha’s game-changing YZ125 in 1996.Photo Credit: Stephan LeGrand
In 1989, Honda’s CR125R had been wicked fast but demanding to ride. Its pro-oriented motor made major power, but only at the upper end of the RPM range. There was virtually no bottom end and very little midrange for the rider to fall back on. For 1990, Honda looked to remedy this one shortcoming by bringing the CR250R’s Honda Power Port (HPP) system to the CR125R.
The Honda Power Port system used a set of sliding guillotine valves, powered by a centrifugally activated ball governor, to alter port timing based on engine RPM. At low RPM the valves would be closed, effectively lowering the exhaust port height for better low-end torque. As the RPM’s climbed, the centrifugal governor would be activated to slide the valves out of the way for better exhaust flow. It was a complex and time-consuming system to work on, but it provided Honda’s two-strokes of the era with exceptional performance.
The 1990 CR125R was the first Honda 125 to feature a variable exhaust port for the motor. Prior to the HPP’s inclusion in 1990, the CR125R had relied on the simpler, but less effective ATAC system. The ATAC system (short for Automatic Torque Amplification Chamber) used a small subchamber at the front of the exhaust port to increase head pipe volume at low RPM’s. When RPM’s climbed past a pre-determined amount a butterfly valve would close, culling off the ATAC chamber and allowing exhaust gas to flow straight to the pipe. In theory, the system was like having a “torque” pipe and a “rev“ pipe all in one. In reality, the ATAC was never as good as more advanced systems like Kawasaki’s KIPS (Kawasaki Integrated Powervalve System) at producing a broad power curve.
I pulled a lot of holeshots on my #291 1990 Honda CR125R in the early nineties. It was an excellent machine that felt like a rocket after getting off my rather slow ’89 YZ125. If not for the gruesome forks, it would have been the perfect 125.
MXA compared these forks to a Roman catapult and they were not far off. These first generation Showa USD forks were just a mess. As delivered, they were badly under-sprung with incredibly harsh damping. The phrase “mid-stroke harshness” entered the lexicon because of these jackhammers. In addition to their abysmal performance, they also suffered from severe particulate contamination that demanded constant cleaning and disassembly. Photo Credit: Honda
The heart of the HPP system was a set of sliding valves placed at the top of the exhaust port. These guillotine valves varied the height of the exhaust port based on engine RPM. At low rpm, the valves were closed to provide the most efficiency. As the RPMs climbed, a centrifugal-ball governor engaged and slid the valves open for optimal flow. In use on the CR250R since 1986, the HPP was revered for its performance but reviled for its complexity. The valves and their associated springs, cams and pullies were quick to need servicing and tricky to adjust correctly.
The new HPP motor on the ’90 CR125R offered a stronger midrange and better low-end response than ’89. Top-end power remained the motor’s strong suit, but now riders of lesser skill at least had a shot at keeping it on the pipe. Photo Credit: Honda
The new HPP motor turned out to be a huge success on the 1990 CR125R. The mill retained its screaking top end power while gaining a much needed mid-range boost. The HPP did not do a lot to boost the low-end torque, but even a small increase was welcome. With its smooth-shifting six-speed transmission and bulletproof clutch, it was a snap to keep the Honda humming. Just pin it, wait for the competition to fall behind and snap off another shift. Overall, it was still primarily a pro-oriented powerband, but now it was a somewhat friendly pro-oriented powerband.
In 1990, noted bike collector Terry Goode ran a company called On The Line Racing that specialized in importing Tecnosel products and super trick Honda accessories like this aluminum tank. Besides being the US Mugen distributor (Mugen was Honda’s Hot Rod division started by Hirotoshi Honda, the son of Honda Motor Company founder Soichiro Honda), On The Line Racing also sponsored Ty Davis on his way to the ’90 125 SX title. Photo Credit: Stephan LeGrand
While the changes to the motor were a rousing success, the changes to the suspension for ’90 were less so. In 1989, Honda had dropped its excellent 43mm conventional forks in favor of Showa’s new upside-down forks on the CR250R and CR500R. Thankfully for 125 owners, however, the USD forks had been left off the CR125R.
Aerial maneuvers were easy on the light and slim ’90 CR125R. Photo Credit: Dirt Bike
Unfortunately for 1990, the new 45mm Showa inverted forks made their way to the CR125R. On the track, they proved only marginally better than the dismal ’89 versions had been. In stock condition, they were undersprung and very harsh in action. There was a nasty spike in the mid-stroke that started out bad and got exponentially worse as the fork’s oil deteriorated.
Mike Kiedrowski and Jean-Michel Bayle took the CR125 to a lot of victories in 1990. Photo Credit: Mike Sweeney
That deterioration did not take long either, as all these early Showa USD forks suffered terribly from particulate contamination. As the forks internals rubbed against each other, the inner tubes would shave off tiny pieces of aluminum into the oil, contaminating the fluid and interfering with the dampening. If you rode a lot, the contamination was so bad you literally had to change your fork oil once a week if you did not want to suffer a noticeable drop in performance.
The shock on the CR125R was set up just as poorly as the forks. It was harsh in action and jarring over rough terrain. The brakes, on the other hand, were excellent. They worked flawlessly, providing class-leading stopping power and requiring little maintenance. Photo Credit: Honda
The Showa shock on the ’90 CR125R was no better than the atrocious forks. Much like the front end, the rear provided a harsh ride over any terrain. The damping was overly stiff and punished the rider when not ridden aggressively. It was unforgiving and choppy over braking and acceleration bumps, with a nasty habit of kicking sideways at inopportune moments. No amount of adjusting clickers could sort out the CR’s ride, and the only real option was to send it out for a re-valve. At least the shock’s oil would last more than a week between services.
Small changes to the chassis for 1990 added up to an excellent handling 125. Photo Credit: Honda
To this day, I love the looks of the 1990 CR’s. The CR250R, with its swoopy new bodywork, was definitely the pick of the litter, but the 125 and 500 were still lookers with their 1988 vintage lowboy bodywork and monochromatic paint scheme. Photo Credit: Dirt Bike
Amazingly, in spite of the CR’s terrible suspension, the bike was an excellent handler. Honda had made several changes to the chassis for ’90 to fine tune the handling and most of them worked. They added 7.5mm of trail to the head angle and stiffened the front end with a larger steering stem. That combined with a slightly relocated motor and ultra-ridged front forks gave the CR a pinpoint steering response. It could grab the inside and rail the outside with equal aplomb. Front wheel traction was excellent and the bike felt light and flickable in the air. Its only real handling weakness was its propensity for headshake. Once you got the suspension fixed (or at least improved from god-awful to semi-terrible) the bike was less busy than previous CR’s and at least rideable on fast tracks. Overall, the chassis package was excellent on tight tracks and a bit dicey faster ones.
I loved this bike in spite of the terrible suspension. Even after getting both ends re-valved and spending countless hours trying to dial it in, the suspension was never great. Even so, it was fast, light, tight-handling and bulletproof. In my book, that was a fair trade-off.
The detailing on the CR was typical Honda for the era. The brakes were powerful, with good feel and completely trouble free. The orange-red plastic (still my favorite Honda color) fit perfectly and was extremely durable. Best of all, the little CR was virtually indestructible. In the early nineties, both Kawasaki’s and Suzuki’s 125’s had some serious issues staying in one piece, but with the CR that was never a concern. As long as you cleaned the air filter regularly the Honda would run forever.
A great bike with crap suspension, the 1990 Honda CR125R was the perfect machine for fast pros that could make the best use of its prodigious power advantage. Photo Credit: Honda
The 1990 CR125R would set the tone for Honda’s 125 offerings for the first half of the nineties. A blazing fast motor, in a sharp handling chassis, saddled with stone-age suspension. The rocket motor and unquestioned reliability were enough to get many a rider to overlook the terrible suspension. If these early nineties CRs had been blessed with the suspension off a Kawasaki, they would have been unbeatable. As it was, they were flawed, but brutally effective race machines. In the 125 class, power was everything and that was the one thing the CR125R had in spades.
