1982~1984 MVX250F

The roots of th NSR250 can be traced all the way back to the MVX250!

The 3 cylinder MVX, and its single cylinder 125cc baby sister, the MBX, were Honda's first real  attempt to capture the 2-stroke road bike market way back in the early 80's. It's chassis was extremely similar in design to the VT250 4-stroke V-twin, complete with the same "in-board" disk brakes.

Although many people still associate the 3 cylinder V-type engine with the NS400R, there are no common parts between them, only the configuration and the use of Honda's ATAC (Automatically-controlled Torque Amplification Chamber), an early power-valve system, link the two models.

The ATAC and HERP system worked by effectively lengthening or shortening the exhaust's tuned length to optimise the reverse pressure waves at the exhaust port, and thereby forcing any escaping mixture back into the cylinder.

The MVX250 was available in 1983 and 1984, as a Japanese market only model, but the MBX125 was shipped to Europe where, although not as popular as Yamaha's RD series, still sold extremely well. All MVX, MBX, and trail bike engined MTX (125 & 200 single cylinder versions) used cast iron bores.

1985 NS250R MC11

The NS250R MC11 was introduced in 1985 and was the  leading edge design destined to be the ultimate configuration for a twin cylinder 2-stroke motorcycle!

It sported both an aluminium frame and  swingarm, unheard of on a road-bike in it's day, along with Honda's trendy Astralight wheels. Again Honda used the ATAC system similar to the MVX, but had now introduced a nickel-silicone carbide (Nikasil) coating on the cylinders for reduced friction and greater wear resistance. 45hp @ 9500rpm out of the showroom made the NS250 an instant hit with Japanese sport riders and club racers alike!

It's design and styling was taken directly from the works RS250R's of that era, a bike that was cleaning up in GP's and eventually allowed Freddie Spencer to win both the 250 and  500 World GP titles in the same season!

A naked (unfaired) version designated the NS250F was also available. It came without the Astralight wheels or alloy swingarm. It was never as popular as the NS250R, and today is extremely rare!

1987 NSR250RG MC16

The first of our beloved NSR's, the MC16 was released in the autumn of 1986 as the all-new 1987 model. Everything was changed and updated... absolutely nothing was left of the old NS250 except the "Nikosil" plating on it's cylinders!! Originally only available in Fighting Red for the first 6 months, it was joined by a blue and white version in March 1987.

The MC16 was Honda's bid to compete with Yamaha's recently introduced TZR250, and at the time, it's new 3-spoke alloy wheels, heavy duty box-section frame and swingarm, and racy styling made the TZR look comparatively conservative! Although it made the same power as the MC11 due to Japan's licensing laws, it weighed some 20Kg less, and utilised the radical new RC Valve variable height exhaust power valve system, making it an extremely agile but flexible bike for its time! Although only ever a JDM (Japanese Domestic Market) machine, the motor once delimited was quite capable of making 55hp, easily making it competitive with the RG250, KR250, and TZR250, and in full race TT-Formula 3 trim was capable of almost 70hp!

1988 NSR250R MC18 R2J & R4J

In late 1987 the MC18 was unveiled for 1988. It was once again completely revised from it's earlier counterpart, and went on sale in Japanese showrooms in January 1988. It's official designation was NSR250R-2J.

It's racer silhouette, higher swept pipes, and the now familiar 6 spoke Enkei alloy wheels, combine with the almost token gesture of a headlight and mirrors to make it a real racer for the highway! The bike was capable of winning races almost "out of the box", producing in excess of 60hp in standard form with the simplest delimiting modification! It took handling to unheard of levels with it's fatter, lower profile rubber and uprated brakes, and created a following still strong with NSR fans today. The MC 18 is probably the closest relation of all the NSR's to the RS250 race bike. In fact, the MC18 F3 parts manual almost reads like an RS250 manual and a version of the MC18 Mk2's PGM-II was used on the RS right into the new millenium! 

An interesting note is Honda's first use of a "double bubble" screen way back in 1987 as an aerodynamic aid!!

Again the MC18 was available in red and white or blue and white for the first 3 months, before it was joined by a limited edition Rothmans coloured SP edition, the MC18 R4J. Although it was designated an SP, the only real difference between this model and the earlier versions were it's Magtek magnesium wheels and race replica paint. 

All MC18 Mk1 SP's were designated R4J and painted in Rothmans Racing colours only.

1989 NSR250R MC18 R5K & R6K

The face-lift MC18's went on sale in Japan in February 1989 and were immediately available in 3 colour schemes, the obligatory red & white and blue & white, but also a new black, red and silver-grey based on the colours of the successful SEED Racing team. These R5K models are easily identifiable by their high swept silencers, the stainless steel rear pipe from the expansion chambers to the silencers, and the sleeker windshield. They also had 4 large holes in the belly pan instead of the multi slotted panel like the earlier bikes.

The differences were more than cosmetic however... under the seat unit, away from prying eyes, the first of the "new generation" 3D PGM's was installed. This ignition unit was identical in appearance to the RS250's PGM-II but with a tamer ignition map for increased reliability and road orientated performance.

The R5K's were the first model to be fitted with a new 150 section Bridgestone rear tyre too, but still had no multi-way adjustable suspension, although a rear shock, c/w ride height adjuster, was available as an HRC TT-F3 option. No R5K SP's were released so there were still no dry clutch models, but the whole range benefited from an updated closer ratio gearbox. First gear remained the same, but the following 5 gears were closer. The R5K and R6K rear sprocket size was also increased from 41T to 42T, giving the stock bike more punch when accelerating, but the resulting final drive and closer ratios lowered the effective top speed a little, but as these bikes were speed limited anyway, it wasn't of prime concern.

The R6K models were the first true SP's. They sported the similar gold Magtek magnesium wheels as before, but now with the benchmark 150/60 series tyre, first seen on the R5K. This new SP also had adjustable suspension front and rear; spring preload and rebound dampening on the front, and spring preload, rebound, and compression dampening on the rear, and an all new dry clutch based on the RS250 race bikes. Released to compete with Yamaha's new TZR250 Reverse Cylinder, Suzuki's first RGV250, and Kawasaki's KR1, it was (and still is) an extremely competent road and race bike capable of in excess of 70hp in full race trim! 

All R6K SP's were only produced in white and silver Terra Racing colours.

1990 NSR250R MC21

Unveiled in late 1989 as the new 1990 model, the MC21 took the 2-stroke world by storm, and completely re-wrote the rule book on how a 250 2-stroke should be built. The craftsmanship was superb, and the new features were groundbreaking!

The MC21 now utilised the PGMIII ECU taken from the legendry RC30 superbike (only now being utilised in GP250 by official HRC NSR's incidentally!!), and coupled to throttle position and gear position sensors, controls both the timing of the RC Valves, air correctors and ignition advance to give outstanding low end tractability. The PGM-III features a true 3D ignition and a different map for each cylinder. 

In keeping with their racer for the road image, the famous Gull-Arm rear swingarm was copied from the RS250 of Luca Cadalora, as was the frame design. Even the mounting point for a steering damper was kept in place! The body-styling was based on the 1988 and 1989 RS250's, with just a few basic concessions like lights and a rear pillion seat!! The rear wheel diameter was decreased from 18" to 17" and widened to 4.5" to run the latest tyre profiles and compounds.

3 NSR250R colour schemes were released, the usual red & white and blue & white, along with a red and black model, and the R model became Japans best selling 250 2-stroke sports bike. To mark its success in the market and on the track, 2500 SP models were released in 1990, all in the Cabin Racing colours of red, white, silver and gold. Again, like the MC18R6K, they all had the gold Magtek wheels, adjustable suspension, and dry clutch. The MC21 also now featured a closer ratio gearbox with a taller 1st gear and an improved shift mechanism.

In 1991 the first SE (Super Edition) was launched, bridging the gap between the R and the SP models. This was basically an SP but with the cheaper standard Enkei alloy wheels, and saved the buyer approximately ¥80,000. The SE's were sold in the Honda Flash (red, white and blue) colours, and 1500 limited edition SP's came in Pentax Racing livery.

For 1992 the bike remained unchanged, except for different colour schemes. The SE was now available in white and red, or black and red, and 1500 limited edition Rothmans coloured SP's were released. The R model still remained Japans best selling 2-stroke 250!

The only change to the line-up in 1993 was the limited run of 900 Commemorative Edition SP's, easily identifiable by the HRC logo in place of the NSR logo on the fairing. This limited edition was basically an attempt to sell the last of the MC21's before the arrival of the new model!

1994~ NSR250R MC28

In November 1993, the first MC28 went on sale. The styling was only subtly changed, with the seat unit and nose fairing mimicing the factory NSR500 and NSR250 respectively. There was one major styling difference though... the Pro-Arm rear swingarm. This swingarm, originally designed and used on the RC30 for endurance racing, was the last word in styling!

The MC28 was also the first and only Honda to utilise the PGMIV, activated by the much hyped "Smart Card", a device initially marketed as the ultimate tool in engine management! The idea was to be able to use several different cards, each with their own ignition characteristics, for any given track or weather condition. It was also the first production bike to sport a digital display. In reality however, the PGM-IV only served as a clever restriction aid introduced by Honda to comply with Japans ever increasing clampdown on power output and licensing laws. In fact, the PGM-IV makes the MC28 the costliest and hardest of the NSR's to derestrict.

Although up on weight and down on power, the MC28 still remained the ultimate 2 stroke race-rep', with only Suzuki's 1996 RGV250R VJ23 trying to keep pace with the NSR's ultra high specification.

Throughout its years (1994-1999) the MC28 remained virtually unchanged mechanically, and all three standard models were still available; the R, the SE, and the SP. The 1994 SP was again released in Rothmans colours, with a limited run of 1500 bikes, and in 1995 another 1500 limited edition SP's were released in HRC Racing Colours.

In 1996 the R model was discontinued, and only the SE and SP were sold. Only 1000 SP's were built, and were painted in Repsol colours to commemorate Mick Doohan again winning the World GP championship title.

In 2000 Jha were the only company consistently supporting the NSR250. They bought the majority of remaining bikes and would sell them in any guise from stock to full race, including ram-air, light weight race bodywork, and titanium expansion chambers.

Sadly, in 2001 after correspondence with Jha, we were informed that there was no longer a stock of "new" bikes at their workshops, and although still supplying a wide range of spares and performance products, complete machines were no longer available, and in 2007 Jha eventually ceased trading.

Special thanks to Jha for the updated pictures of their race bike and their continued support over the years. Jha have now sadly ceased trading, which is a crying shame not only for the NSR owner, but for anyone competitively running a competition 2-stroke road/road-race bike, as their products were simply unrivalled in the marketplace and on the circuit.