SUZUKI 2-STROKES

In 1956, Suzuki technicians were developing a completely new competition machine, known as the TT. Based on the successful Colleda, it was the forerunner of the Grand Prix machines. It was a high-performance machine of its day, being able to do over 80 mph and capable of out-performing machines with far more powerful engines, despite making only 18bhp from its 250cc twin-cylinder two-stroke engine. With its indicators, and built-in, four-speed gearbox it was considered very advanced.

As 1958 rolled in, Suzuki Motor Co. Ltd. had 50, 125 and 250cc machines in its arsenal. In May of that year it introduced the "Suzumoped SM", using the successful Mini Free power plant mounted in a spine-type frame.

In October of that year, Suzuki introduced their corporate "S" logo, which was used on all their bikes and is still used by the motorcycle division.

June 1960 Suzuki takes their factory-prepared 125cc Colleda racers to the Isle of Man to compete in the lightweight TT. Although they did not win at their first attempt, they managed respectable fifteenth, sixteenth and eighteenth places. Suzuki was anxious to show the buying public their machines were fast and reliable.

The 'Selped' moped was one of the company's biggest sellers; it was later boosted to 80cc, and was to become one of Suzuki's best sellers, the A100.

By the end of 1962, Suzuki had won their first World road racing Championship in the 500cc class, and in America, Suzuki was setting up their new headquarters under the "U.S. Suzuki Motor Corporation" banner. The company decided that it needed to test its prototype machines on a purpose-built track, construction was started in 1962 on its 5-mile Ryuyo test track near the factory and was completed in 1963.

Suzuki made steady progress in road racing and in 1964 they surprised the road-race fans by entering into the world of motocross Grand Prix. Entering the Japanese motocross champion, Kazuo Kubo, in the Swedish 250cc Grand Prix, but without the same success they had achieved earlier in road racing. Although their machines were fast, they did not handle well. Suzuki's engineers went back to the drawing board and returned to Europe in 1966, with completely redesigned machines, which saw moderate success. In 1967 Suzuki signed up their first non-Japanese motocross rider, the Swede, Olle Peterson.

It was European, Joel Robert, who in 1972 won the World Championship, Suzuki's first. Suzuki won several more times, and won the 125cc class every year since 1975. October 1967 saw the introduction of the 500cc Titan road bike. This was known through its 11-year production as the Cobra, Titan and the Charger, finishing production as the GT500. It was a 500cc twin-cylinder two-stroke, which handled quite well and became very popular.

The trail bike, with its on and off-road capabilities, was the big success story for all the Japanese manufacturers and in March 1969 Suzuki launched their TS range, with knowledge gained from the motocross World Championships.

But it was with the two-stroke machines that Suzuki achieved their greatest successes, both on and off the track. In October 1969 they opened another factory at Toyama to produce small capacity two-strokes.

A machine, which took the motorcycling world by surprise, was the astonishingly quick GT750 Two-Stroke triple (known as the Kettle or Water Buffalo), capable of well over 110 mph. At 540lbs, it was not a lightweight, but with 67bhp it could push itself from 0 to 60mph in only five seconds.

With the confidence gained from producing the large capacity GT750 Two-Stroke triple, Suzuki announced to the world that they would introduce a totally new 500cc four-cylinder, Two-Stroke racer called the RG500. As a mater of fact, the RG500 was to become the single most successful racing machine of modern times, and by the time it had completed three racing seasons it had won two World Championships with Britain's Barry Sheene aboard.

A model worthy of mention is the RE5. This was Suzuki's attempt at producing a rotary-engine machine. Based on the Wankel design from Germany, it proved to be a costly and expensive failure.

Walter Wolf Suzuki RG500, RGV250SP Gamma

Michael Hall from the States sent these photos and a few words about his rare Walter Wolf Suzuki, 250SP Gamma and his Kawasaki Z1s, just to make us all wish we had the foresight to keep our classic bikes and not sell them off, only to pine for them later...

"1986 Suzuki RG500 Model RG500EW-2W

7995km or 4970 actual miles.

All original serial # HM1A105234

Super rare 1986 Suzuki RG500 “Masaru Mizutani Replica” one of only a limited number of 500cc Japanese Spec models. Made to commemorate the “1979 All Japan Champion, Class 750A, and all Japan 1981 Champion 500cc, Masaru Mizutani who at the time was sponsored by Walter Wolf Racing."

"This bike is often referred to on this side of the pond as a Walter Wolf Special Edition, but it differs from the Canadian version graphically, it has integrated turn signals, a fuel gauge, passing lights, Walter Wolf instruments, key, and different wheel and seat color.

In my opinion a more complete package and attractive as a bike. I did a considerable amount of research on this model both within the US and abroad over the last several years and have found only one other example, none in the US.

What few examples I found were the more common RG400 model, that are identical with the exception of the “500” decal, and engine displacement due to the Japanese license restrictions at the time, limiting riding to just a few if displacement exceeded 400cc."

I have heard, although I have not been able to confirm this model was actually produced to distribute the remaining factory stock of RG500s after actual production had ceased. Given that the Vin number is one of the last, there may be some truth to the story.

I also have collected over the years Walter Wolf memorabilia such as a watch, patches, badges, bike stand, eye glasses, cologne, a helmet, posters, jigsaw puzzle, etc and even a set of leathers worn by Gary Berge, 1985 Canadian National Open Production Champion sponsored by Walter Wolf."

If you'd like to read more about the amazing Walter Wolf, Google the phrase " Who is Walter Wolf and why is he wanted? The Globe and Mail ".

He's an unbelievable character who might rightly be called an international man of mystery. It makes for interesting reading and centers around Wolf's life outside the world of motorcycle racing.

1997 Suzuki RGV250SP Gamma

"This 1997 VJ23 RGV250SP (Gamma) “V” Model in Lucky Strike colors is probably the second rarest production Suzuki, only to the ever-elusive 1986 GSX-R 750R.

1996-1997: Quoted power; 1997=70hp from the very rare 'SP' model (sports production) with new 70° V-Twin engine “V” model. According to Suzuki there were only 357 of these models produced. 119 were pink, 119 blue/white, and as shown 119 in the Lucky Strike paint.

This bike is “mint” with approximately 12390 KM or 7600 miles on the clock. Includes rear pillion, owners and service manual. This bike was never exported to the US. And unfortunately was the swan song for the RG line. The best should always come last. The engine however survived until the present. We just think of them as made by Aprillia."

And if you thought that was pretty jealousy inducing, read this below and weep at the thought you don't own five (5!) mint Kawasaki Z1's.

Suzuki RG250 Gamma Walter Wolf limited edition

Kevin Waugh explains in fine fashion his enthusiasm and experiences with Suzuki 2-strokers

The piston-port Suzukis

"Early on it was clear to me that simple design and good engineering were the first things to look for in a motorcycle. My passion for road going two strokes was a reflection of that notion.

When the Hustler and the Titan first appeared on the scene I was still in short pants and hadn't a clue. My first Yamaha was amazing for several reasons but I just want to talk about reed valve induction in the Yamaha's and the older piston port designs as seen in the Suzukis I so enjoyed riding.

As the piston port type came first I'll start there. The T-20 X-6 Hustler A.K.A T-250 and the GT-500's and later, the GT550 triple were technically vintage by the time I was riding them. The good thing about these engines was the smooth, fat power curve throughout most of the rev range. Suzuki were interested in providing usable, predictable broad delivery of power. They did this by determining the best locations for the transfer and exhaust ports not only in radial position but in the vertical orientation as well.

Well, so far there is nothing new here. All two strokes operate in the same manner in theory. It is in practice where it gets interesting.

General riding impressions

My riding mostly consisted as it does today of town and country work, I would commute to and from work in the city and almost every weekend 140 miles both ways and occasional side trips and road trips on the weekend. I also drove an RD 350 to Toronto and back and attended many race meets and drove to Vancouver and Quebec City on the KZ1000 as well. The miles add up and I did it for 25 years.

I am not interested in going into technical arcana but I do want to discuss how it felt to ride these machines with some quite different power delivery characteristics as it was the cornerstone of the riding experience.

I'll start with the T-250 as it was almost new and produced factory level output and I will use this as a standard staring point. Snicking into first gear and accelerating away from a stop was a gentle affair and there was enough power on tap to short shift around town, pretty sedate and easy going, a pussy cat. I rarely drove it like that, to boring. At idle, that little motor would happily burble away as tame as a Lawnboy. At about 4000 rpm, it would start to get on the pipe and the intake noise became more prominent. The bike was now a lively minx ready for a scrap.

The suspension was getting excitable and the bike was begging for a taste of the lash. I just wanted to say that. From that point onward to red line was in the meaty part of the power brand. As the chassis was small and relatively light ( the side covers were still steel) the impression of speed was great.

Power dropped quickly close to redline (8000 rpm) Banging through the six gears and speed shifting and maneuvering about town dodging other bigger vehicles was like a fly evading the swatter. I took the front suspension apart and put it together with good heavier fork oil and home made spacers as needed on every machine I owned as a matter of routine maintenance. A bonus here was the radial steering damper which proved quite useful.

It became a matter of using every single horse power to the best possible effect. With six gears and an itchy left foot keeping things at a brisk boil became second nature to me. I was pretty skinny back then and it helped. I had to think ahead a bit to make sure that if I got into a tight spot I had sufficient space to haul on those little twin leading shoe drum brakes as they were not the instant on variety.
All I had to do was think about a direction and the bike instantly went there with no fuss and no drama and it did it right effing now. The chassis was so harmonized with the engine that slicing through the traffic was a huge pleasure and confidence inspiring from such a small and unthreatening package.

I always felt directly connected to the machine and handling feed back was honest and visceral, which I have always thought, the mark of excellence. It was the power delivery mated to a very competent frame and suspension that made all this possible. On the highway the story was different. Here the machines short comings started to become apparent. I could accelerate hard up to speed, which I always did, but I would top out at 85 mph. Top cruise was 70 MPH but that was too buzzy and I quickly tired of the pace and rolled the throttle back to 65 mph. This was one nimblest bikes I owned and I loved it. A strong head or cross wind would really make you work hard to keep the pace up, thanks to the six speed gear box I could always find a gear that worked with any given load requirement.

In a cross wind the lean angle was ridiculous and one could get blown around quite a bit due to the light weight of the bike. I needed to think twice before attempting a pass as there really was no extra horsepower and I had to bide my time waiting for a good long run at full flog.

The most serious problem with the piston port design was the inefficiency of the cylinder scavenging and sloppy metering and control of the fuel charge in the cylinder relative to the reed valve type induction on the Yamaha's which we will look at later. This meant that energy was basically going out the exhaust port in the form of unburned fuel as untapped potential. In racing tune, many of these problems were addressed at the expense of ease of use, civility and longevity. There is going for Sunday drive and then going for a Sunday DRIVE!
As noted above, the GT500 had all the same characteristic's as the 250 in terms of power delivery and I think it should be remembered that these engines were so good that they became Suzuki's racing engines for their racing program, this was especially true in the T500 which morphed into the legendary TR500.

The engineering was highly refined and the strength incorporated into the engine design was meant to resist the hard abuse of international road racing competition. That Suzuki was able to further tame these power units is a testament to their technical prowess. A four stroke power plant of the same power output would have to be almost twice as heavy and twice as large in capacity and certainly twice as complex.

On machines where every pound of weight is critical to performance, the two stroke was the only solution especially in the under 500 c.c. classes. In engineering, compromises might be necessary but a good engineer knows how find good solutions.
The GT500 was bigger, longer and heavier than it's little brother but in many ways it had a different mission. First introduced in Britain as the "Cobra", I'm not kidding, this company also brought us the T-200 "Invader", the T500 was a revelation.

In the scale of things it was the the second most powerful of my two stroke machines at 46 hp, the GT550 had 48 hp and the Yamaha's averaged 36 hp and the T-250 was 32 hp. It doesn't sound like much today but back then it was a pretty big number for a 500 c.c. motor. The below road test is accurate as to the riding experience and I have little to add except to say that it was steam age fun. As for the look of thing, it possessed that beautiful classic style which it shared with the T-250, hinting of power and elegance and a certain grace all verified by riding of it. It made a wonderful exhaust note, hardly what I would call loud but it had a insistent growl with mid range pitch coming from those long sweetly shaped silencers.

I used to tell my friends that when given the stick she didn't so much accelerate hard as just pick her skirts and hustle up the road. I did like the way it looked just fine but I'd never buy another one as there are better classics than this one. Suzuki used some pretty heavy wall steel tubing for the frames on these bikes so they were not light but had significant strength which paid off at high speed with good stability. The welding on the frame was all business and not pretty but generally much the same as everybody else's.

The GT550 triple had many of the same familiar mechanical details and design philosophy and target market but was a different experience. Considered a class winning middle weight sport touring mount, what a mouthful, this rig was Suzuki's replacement for the long in the tooth GT500.

Sharing much of the same technical features as the other bikes in this essay was first introduced in 1972 complete with "The Ram Air" scoop which really worked as it did on the GT250, GT350, GT380 and the Yamaha RD400 Daytona. How did it work you ask? Well let me tell you, it served two purposes, one was to cool the cylinder heads and the rear face of the cylinder barrels and obtain better as in lower and more consistent operating temperatures which meant it could run leaner.

The better temperature control meant it was possible to maintain tighter internal clearances and by extension produce more power over longer periods at high throttle settings. It did. The second purpose was to control engine noise. It did. Many, including myself thought it was a styling exercise when really it was good design.
Yes I'd wanted a triple since I rode my pal's Kawasaki 1972 S-2 350 back in 1976.
Compared to to my 1973 RD350 the S-2 was a crazy 44 hp hobbyhorse. I thought of the potential it had if some one could sort out the handling, brakes and tires and the seat, it might be a little blaster and it had an oh so smooth motor. Okay I fell in love, unwise and improvident. The story of my life.

Not nearly as refined as the RD or the later Suzuki's it still had that hooligan charm, and a dull do nothing power curve until it hit 6000 rpm when the power output made a huge leap and the front wheel shot skyward, a two wheeled "Rowdy Man". A late model KH400 would nice to have now.

Here was my chance to own a two stroke triple and after all those years and bikes past, I took it. Hauling the Suzi tripe home I spent several months doing a through tear down accept for the motor which was a sweet runner with 27000 mph on the odometer. And I made the usual modifications to the brakes, chassis, forks and handle bars etc.

I was going to make rear sets but never got the chance as I put Suzi into the side of a lady deer at 70 mph under a full moon when the doe u-turned on me at the last second, another perfidious female. There was no time to brake so I had maneuvered around her bum and then she tagged me but good. I had put my passenger helmet in my tank bag and when I hit the livestock and my chest hit the helmet and crushed a lung and I lost consciousness. Don't put helmets in tank bags! Any way that is a story for another time.

This now rare machine was a write off and I had a third degree shoulder separation, three broken ribs and bruises and scrapes up and down my left side and my feet hurt a lot. It took me months to piece together the chronology of the sequence of events using the evidence available. A very interesting study in it's self, sort of like CSI without the pretty girls.
What did I like about this one. It came with tapered roller bearings already installed. The club man bars were prefect at speed and the reduced leverage helped increase the precision of the steering inputs, but were slightly uncomfortable around town.

The motor was strong as could be, the triple set of breaker points never wandered out of spec. And the brakes were good enough but unspectacular, it had good stability, a fabulously smooth power plant with a broad spread of power.

Good highway manners and enough jam to pass most things on the road. The modified seat was very comfortable and roomy. Some thing should have mentioned earlier is that the "Posi-Lube oil injection system was the best of them all. Yama-Lube also gave great results. Older guys in cars would look at the bike and tip their heads in my direction and give a discreet salute to me as they remembered their youthful adventures on such a beast. That was a gratifying moment.

On the flip side the GT550 had a heavy but strong frame, an 18 inch D.I.D. front wheel would have worked better. I would have liked more power in the top end. This weakness showed it self every time I went for the "Ton" as it seemed to take a long time to get there with still 1000 RPM before redline but I could have probably changed the rear drive sprocket by about 2 teeth and solved it that way and kept the original power band.

That plumbers nightmare of an exhaust system was very heavy and gobbled up cornering clearance although I never got leaned over far enough to touch down and just as well. The way I drove it fuel economy was not brilliant, but I really didn't care. With the exception of the fuel consumption all of these items were easily fixable.

Every two stroke had similar problems to overcome and each manufacturer dealt with them in their own unique way."

Suzuki GT550 model history 1972—1977

Suzuki introduced a trio of three-cylinder two-strokes in 1972: the air-cooled triples GT380 and GT550 and the new flagship, the liquid-cooled GT750. Both of the air-cooled models featured Suzuki new patented Ram Air cooling system that forced cool air under a aluminum shield mounted on the top of the cylinder heads and improve cooling. The system really worked and the GT models didn't suffer from the problems that usually are attached to air-cooled two-strokes: overheating engines and loosing power as a result of it. According to the test rides from those days the GT380 and GT550 delivered the same amount of power even after hard use. You can read more of the Ram Air Cystem on a GT550 road test, published in Cycle World, Jan 1973.

The GT380 had six gears but the GT550 with its wider power range worked just fine with its 5-speed gearbox. The GT550 (called Indy in the USA). The model was sold until the introduction of four-stroke GS550 in 1977.

1972 Suzuki year code: J

At first the GT550 had drum brakes a disc brake was introduced already during its first model year (see the pictures). The GT550 wasn't as fast as its big brother but it was a perfect compromise between the GT380 and GT750. The low-mounted exhaust pipes decreased the ground clearance significantly in the curves and the the suspension was quite soft (as in most Suzukis in the early seventies) but othervise the GT550 was smooth, fast and durable. The Suzuki engineers had done a fine job with it.

After the introduction of the disc brake at front, the model didn't go through any significant upgrades, expept for the paintjob.

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