For this week’s selection from Greg Primm’s 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.

In 1990 Honda was on quite a roll in the 125 class. They had owned a virtual stranglehold on the division since the groundbreaking ’83 model CR’s had made their debut. 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 nearly a decade of dominance, the all-new ’90 CR125R would have 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.

The ’89 CR125R had been an excellent machine with very few flaws. If anyone had any real complaint with the bike, it was usually centered on its fast but very pro oriented motor. The ’89 CR125R mill made major power, but all that power was in the upper end of the RPM range. There was virtually no bottom end and little midrange for the rider to fall back on.  For 1990, Honda looked to remedy this one shortcoming with an all-new Honda Power Port (HPP) motor. 

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 true to life “power valve” for the motor. Prior to ’90, Honda had relied on its simpler, but less effective ATAC system on their 125’s. The ATAC system (short for Automatic Torque Amplification Chamber) used a small sub chamber 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 “low-end” pipe and a “top-end “pipe at the same time. In reality, the ATAC was never as good as more advanced systems like Kawasaki’s KIPS (Kawasaki Integrated Powervalve System) at producing broad power curves. 

I pulled a lot of holeshots on my ’90 CR125R It was an excellent machine that felt like a rocket after getting off my rather slow ’89 YZ125. If not for the gruesome suspension, 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 undersprung with 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.

For 1990, Honda would address this issue by incorporating their highly regarded HPP system into their 125 for the first time. The HPP made use of two sliding valves at the top of the exhaust port to vary port timing and shape based on engine RPM. The HPP system was very complicated, using dozens of moving parts, but it provided excellent performance. It had been used on Honda’s CR250’s since ’86 to produce some of the best engines of the era. Its only real drawback was complexity, because servicing the HPP could be quite a task for the uninitiated.

I ran one of these Pro Circuit pipes on my ’90 CR125R. It took what little low to mid power the bike had and turned it into all top-end. For a pro, it was probably a good trade, but for me it made the bike very hard to keep on the pipe. I ran the Pro Circuit set up for a few races before going back to the stock pipe which provided a much easier to ride power curve.

The new HPP motor was a huge success on the ’90 CR125R. The mill retained its screaking top end, while gaining a much needed mid-range boost. It was still primarily a pro oriented powerband, with only passible low-end torque, but now at least it was much easier for less skilled riders to keep it on the pipe. Where Yamaha and Suzuki went for the punchy low to mid-range powerband appreciated by novices, Honda went after the faster intermediates and experts who could make ample use of its awesome top end pull. Honda’s only real competition in the motor department in ’90 was from Kawasaki’s radical new perimeter frame KX125. The KX ran similarly to the Honda, with a hard mid-range hit and strong top-end pull. Its one weakness was an even softer low-end than the CR, which made the bike very hard for less skilled riders to manage. Topping off the CR125R motor package was a smooth shifting six-speed gearbox and flawless clutch. When you combined the CR’s class leading power spread with its near indestructability, it was hard to find a better power package in 1990.

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.

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, the USD forks had been left off the CR125R in ’89. The new USD Showa’s were absolutely terrible and a huge step backwards for Honda. For ’90, Honda decided to bring the new school USD’s to the CR125R as well. Unfortunately, the ’90 version of Showa’s USD’s were only marginally better than the ’89 version had been. They were undersprung and very harsh in action, with a nasty spike in the mid-stroke that started out bad and got exponentially worse as the fork’s oil deteriorated. 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. Worst of all they defied fixing, even if you got them re-valved, they were never very good and always delivered a harsh ride. Put plainly, the ’89-’91 Honda Showa USD’s were grim to a level today’s riders just can’t imagine, these forks were just hopeless.

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.

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 for riding at less than 100%. 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.

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. I always loved the orange mist color as well. It made reappearance in 1990 after two years of blood red on the CR’s. This was the last of the clean looking Honda’s for more than half a decade.

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 for tight tracks and passible for 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 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 mist 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.

Honda had quite a ride in the 125 class over the years. They started with a huge lead, only to squander it away in the late seventies. Then in the early eighties, they made a major comeback and dominated for more than a decade, only to lose their way again in the late nineties. Even though it went out with a whimper instead of a bang, the Honda CR125R will always be remembered as the bike that taught a whole generation what motocross was all about.

The 1990 CR125R would set the tone for Honda’s 125 offerings for most 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 CR’s 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.