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# | {{Motorcycle | ||
|name = [[Suzuki]] RG250 | |||
|photo=Suzuki-RG250-83.jpg | |||
|aka = RG250W, RG 250 W, RG 250 Gamma, RG 250, RG250 Gamma | |||
|manufacturer = Suzuki | |||
|parent_company = | |||
|production = 1983 | |||
|model_year = | |||
|predecessor = | |||
|successor = | |||
|class =[[Racing]] | |||
|engine = Two stroke, parallel twin, reed valve | |||
|bore_stroke = | |||
|compression = 7.4 :1 | |||
|top_speed = | |||
|power = | |||
|torque = | |||
|fuel_system = | |||
|ignition = Pointless Electrical Ignition | |||
|spark_plug = | |||
|battery = 12V, 5Ah | |||
|transmission = 6 Speed, constant mesh | |||
|frame = | |||
|suspension =Front: Telescopic fork, [[coil]] spring, oil dampened with [[anti-dive]] <br> | |||
Rear: Full Floater, mono-shock, gas/oil damped, spring preload fully adjustable | |||
|brakes =Front: 2 x 260 mm Discs ,1 [[piston]] [[caliper]] <br>Rear: Single 210 mm disc, 1 piston caliper | |||
|front_tire = {{tire|100/90-16}} | |||
|rear_tire = {{tire|100/80-18}} | |||
|rake_trail = | |||
|wheelbase = 1385 mm / 54.5 in | |||
|length = | |||
|width = | |||
|height = | |||
|seat_height = 785 mm / 30.9 in | |||
|dry_weight = 131 kg / 289 lbs | |||
|wet_weight = | |||
|fuel_capacity = 17 Liters / 4.5 US gal / 3.7 Imp gal | |||
|oil_capacity = 1.2 Liters / 1.3 US qt / 1.1 Imp qt | |||
|fuel_consumption = | |||
|turning_radius = | |||
|related = | |||
|competition = | |||
}} | |||
==Engine== | |||
The engine was a Liquid cooled cooled Two stroke, parallel twin, reed valve. The engine featured a 7.4 :1 [[compression ratio]]. | |||
==Drive== | |||
Power was moderated via the Wet, multi-plate. | |||
==Chassis== | |||
It came with a 100/90-16 front [[tire]] and a 100/80-18 rear tire. Stopping was achieved via 2 x 260 mm Discs ,1 piston caliper in the front and a Single 210 mm disc, 1 piston caliper in the rear. The front suspension was a Telescopic fork, coil spring, oil dampened with anti-dive while the rear was equipped with a Full Floater, mono-shock, gas/oil damped, spring preload fully adjustable. The RG250 Gamma was fitted with a 17 Liters / 4.5 US gal / 3.7 Imp gal fuel tank. The bike weighed just 131 kg / 289 lbs. The wheelbase was 1385 mm / 54.5 in long. | |||
== Photos == | |||
[[File:Suzuki-RG250-83.jpg|600px|Suzuki RG250]] | |||
[[File:Suzuki-RG250-83--1.jpg|600px|Suzuki RG250]] | |||
[[File:Suzuki-RG-250-Gamma-83.jpg|600px|Suzuki RG250]] | |||
[[File:Suzuki-RG250-83--2.jpg|600px|Suzuki RG250]] | |||
[[File:Suzuki-RG250-83--3.jpg|600px|Suzuki RG250]] | |||
== Overview == | |||
Suzuki RG 250 Gamma | |||
The arrival of the RG250 represented a new phase of Japanese engineering. It | |||
was, of course, quicker than the RD250LC, in fact it was just about as fast as | |||
the RD350LC (and it cost nearly as much, too). But there was more to it than | |||
that. | |||
It was functional, using the extra stiffnes of box-section alloy instead of | |||
thinner-walled steel tubing and an engine which was, necessarily, peaky in order | |||
to achieve its performance. | |||
It had good suspension, which worked very well despite the relatively low | |||
weight of the bike and it had a high build quality with lots of neat touches and | |||
well-made parts which made it nice to look at, nice to sit on and satisfying to | |||
use. Much of this was rare in any roadster. On a 250 it was unique. The later | |||
mark 2 and mark 3 models smoothed out some of the peakiness and grew a very | |||
stylish full fairing. The Gammas opened up a whole avenue of production racing, | |||
gave the Yamaha-based tuning fiops a hard time and founded a new industry | |||
supplying cheap aftermarket bodywork which production racers could afford to | |||
crash. | |||
Its cost was out of line with its capacity, but so was its performance, and | |||
nobody seemed to mind. People did mind the precarious sidestand and the pitiful | |||
tank range usually less than 100 miles when used as intended. | |||
Review | |||
Pull the engine revs up near the power peak as you feed the clutch in. | |||
Remember, off idle this thing has about enough power to blow you a kiss from two | |||
paces. Rev, then slide the clutch through most of first gear to keep the engine | |||
pulling strong. For a Bonnie and Clyde blast-off, be careful. Don't let those | |||
revs fall too far, or else the engine's power will go out like a light, delaying | |||
your launch. Unacceptable! Keep that tach needle flashing above 5000. | |||
On a straight piece of road, you're almost violating the 9000-redline in | |||
fifth gear. A tight, 90-degree left-hander pops up on the horizon. Full | |||
attention, please. Apply binders. You get the brakes on hard as | |||
the turn closes in on the Gamma. You can't be clumsy with the rear brake; it | |||
rewards the heavy-footed by locking up. The superb front brakes, sticky tires | |||
and forward-mounted engine set the Gamma's behaviour terms under forceful | |||
braking. Since weight seems to transfer to a point under the front axle, you | |||
just touch the rear brake pedal. Elevating the rear tire under | |||
hard braking is neither unthinkable nor impossible. Watch for mono-wheeling, | |||
front-end style. | |||
Here's the corner, now. Ease off the brakes slightly just as | |||
you toss the Gamma in to the left. Pitch decisively, but be smooth. Too much front brake | |||
during the turn-in and the light rear end will momentarily feel as if it's on a | |||
side excursion. Ragged riding at this crucial moment will have you cultivating | |||
in the roadside ditch. | |||
This Gamma game room has a ceiling about 2000 rpm above its floor. Levitate | |||
in this space by dancing with the gear shift lever. Be in the right gear at the | |||
right time, and you'll be okay. Screw up - and you're on the floor. | |||
Don't forget where this arcade game is going, either, right through the apex | |||
of a corner. | |||
Get back on the power when positive messages come up from the tires, and let | |||
the bike arc toward the outside of the pavement as you reach full throttle. Now | |||
snick/snick, third/fourth, before you nick the close-ratio six-speed back for an | |||
instant to enter the second turn, an 80-mph right-hand sweeper, a corner where | |||
momentum is the key. It exits onto a lengthy sixth-gear straight. | |||
After you swoop through the right, tuck in while the tach needle waivers at | |||
redline in top gear. Be alert. It's time to dive back through the gears and | |||
brake for a left-right-left multi-speed combination. Don't be too aggressive; | |||
the rear wheel has to stay on the surface. The first left is a fourth-gear | |||
sweeper which dumps into a third-gear right. Quick, cooperative steering is | |||
mandatory on this left-right combo: because the brakes are on all the way | |||
from the entrance to the left until you peel off for the right. The 16-inch | |||
front wheel eases the effort to get the hard-worked front tire to do what it | |||
must - turn-brake-stick. | |||
The Gamma does the left-right flip with a touch of "top-side." For a fleeting | |||
instant the bike gets feathery when it's un-weighted during the transition, a trait shared by all lightweight, | |||
race-bred machines. Nothing to get excited about. It just registers in the pit | |||
of your stomach. Concentrate. Exit the third-gear left. Hey, nice combination. | |||
Nice bike. Oops. Stay to the right for the approaching second-gear left-hand | |||
hairpin; set up for a late apex, because you'll get the maximum drive down the | |||
following long straight. Brakes. Careful. Pitch. In and out. Neat! Getting | |||
through these corners like a beam of light reflected from mirror to mirror is | |||
the key to finishing first at the end of the, at the end of the, well, road. | |||
Road? The hell you say. Yes, that's right, road, and on a street bike | |||
no less. One complete with lights, turn indicators, battery, horn and license | |||
plate. The messages sent up from the bike, the feedback from its aggressive, | |||
surefooted, responsive manner speaks racetrack. But you're out there | |||
laughing at those other poor fools who are yanking on lumbering, everyman | |||
motorcycles. What an embarrassment you are for them with this 250. If they only | |||
knew. They've been working with cannons. You've had a ray gun. | |||
It's doubly embarrassing to them when they realize the bike you're riding is | |||
only a 250. Suzuki's RG-Gamma does more than share a name; it carries the repli-racer | |||
connection beyond that of any other street-runner ever tried by Cycle. It | |||
doesn't merely look like the World Championship-winning model; it is, in | |||
many respects, the same. Never mind-that it only displaces 250cc or makes a | |||
modest 30 horsepower at the rear wheel. This 250 is Gamma-like because as it | |||
goes down the highway it responds to rider commands with the same kind of | |||
directness that its namesake, the RG500 Gamma, would on the racetrack. Never before has a motorcycle | |||
been so successful echoing the latest war whoop from the Grand Prix circuits. | |||
Look at this pint-sized Gamma. You've seen it before at places like Imola, | |||
Nurburgring and Silverstone. Lots of today's sport bikes have square-section | |||
frames, but they're mild steel stuff. Now ask yourself what factory ever raced | |||
one made of steel. Exactly none. And how many street bikes have you seen with | |||
aluminum frames? None, unless you take the time to look at the RG250 Gamma. | |||
Suzuki has made the Gamma's entire chassis from aluminum, from the fairing | |||
mounting tabs welded to the steering head to the seat brackets at the rear. All | |||
the welds on the RG, whether easily visible or not, look like the work of a | |||
Michelangelo of torch and rod. These Suzuki guys actually mass-produce these | |||
things. Though its construction bears many similarities with its championship-winning brother, concessions to production-line | |||
practicalities do exist. | |||
In those areas where the swing arm and Full Floater suspension anchor, the | |||
RG500 race-bike frame is built up from aluminum plate and hollow extrusions | |||
welded together; the 250 Gamma uses die-cast aluminum plates welded in place. | |||
The die-castings, which also serve as the mounting points for the | |||
footpeg/muffler carrier, are not solid, inch-thick plates as they appear. Their | |||
backsides are hollow with stress-carrying ribs. Light and strong, these castings | |||
are labor saving devices for the chassis builders. They're also gorgeous. Any extras for ashtrays? | |||
The RG's steering-head angle is a steep 24.7 degrees, the four inches of | |||
trail middle of the road. The steep rake follows current racing design practice. | |||
On the racetrack, where a rider must be able to change the motorcycle's | |||
direction at the speed of thought (or faster), steep rake angles are mandatory. | |||
The four inches of trail is more than an engineer might use on a racer, but on a | |||
street bike it's necessary because normal riders should have a lot of | |||
self-contained, built-in high-speed stability. Race riders learn to cope. | |||
On the 250 Gamma, front and rear suspension are well balanced, though both | |||
seem a trifle light on rebound damping near suspension top-out. Suzuki has | |||
already adapted the GP-Gamma's Full Floater system on many new models, street | |||
and off-road. The company has the single-shock rear system down pat on the Gamma | |||
250, and it matches up to the fork, a 36-millimeter, 5.1-inch travel unit with | |||
Suzuki's ANDF (Anti Nose Dive Fork) system. A steel fork brace, concealed | |||
beneath the front fender, adds more rigidity. On the 250, braided stainless | |||
steel lines connect the brake calipers to the ANDF activating pistons. These lines don't flex, and as a result, the front | |||
brake lever vagueness, so characteristic of many ANDF Suzukis, has been reduced. | |||
With the exception of the shock, the superb Full Floater uses almost entirely | |||
aluminum sheet and forgings. The effective suspension suits perfectly the abuse | |||
the RG250 invitesbusting down backroads as fast as the rider and motorcycle can | |||
go, GP style. A remote preload adjustment knob located below the side-cover aids | |||
preload tuning, but the engineering department left no provision for adjusting | |||
either compression or rebound damping. Rear suspension travel measures a | |||
moderate 4.8 inches, but in light of the rather quick front-end geometry, that's | |||
probably a good thing. Were road surfaces bad enough and speeds sufficient, | |||
great deflections with long-travel suspension might upset the bike's geometry, | |||
and the rider would receive a wobble-message telegraphed to the handlebar. | |||
The gold-finished dual-piston brake calipers are the same excellent units | |||
fitted to the 1983 GS550ES series. The front brake system, apparently a direct | |||
carry-over (minus a little black paint), ranks among the best of the Japanese | |||
OEM stoppers. Your imagination probably can't do the stopping force of these | |||
brakes justice when they're cinched on the Gamma. Five-fifty owners, put this in | |||
your filesthe Gamma weighs 140 pounds less than a GS550. The rear caliper-rotor | |||
combination is a .250-Gamma exclusive. Considering the front brake's phenomenal | |||
power, the rear brake has a light work load, not that you'd want a highly | |||
excitable brake on a wheel that can get airborne under heavy-duty braking | |||
anyway. The small brake rotor saves considerable weight in a place where it | |||
really counts. Comparatively, front/rear brake size is yet another similarity | |||
between the deadly-serious 500 GP and the all-for-fun 250. Those product | |||
planners in Hamamatsu knew what the world's street demons would be doing with | |||
the little Gamma. | |||
Down in the engine bay, the similarities between the real and the road Gammas | |||
end. Building a 250cc version of the disc-valve 500 square-four would have been | |||
outrageously expensive and stupid. Suzuki would have had to mortgage their | |||
General Motors stock to have done it, and were it done, the engine would be a | |||
500. There's nothing too fancy in the RG250 Gamma's parallel twin. The 54 x 54 | |||
Gamma has bore and stroke dimensions identical to the latest production 125cc | |||
motocross engine, and the RG utilizes Suzuki's Power Reed (case reed) intake system. A | |||
pair of equalized 28-millimeter flat-slide Mikuni carburetors feed the cylinders | |||
and draw air from a huge airbox fitted with an oiled foam element. | |||
Since the Gamma is a small bike with a single-shock rear suspension, | |||
components like the airbox and battery must be herded carefully into existing | |||
space. We'll bet the engineers who managed to get 10 pounds of components into a | |||
five-pound hole ride up and down 10-man elevators in packs of 15. | |||
The one-piece cylinder head with its integrated thermostat housing has | |||
squish-band combustion chambers. | |||
Compression ratio is 7.1:1. Below the head, the individual iron-lined | |||
cylinder assemblies flow coolant in the most efficient way possible. From the | |||
water pump, coolant goes through the upper half of the horizontally split | |||
crankcase and directly to the bottoms of the cylinders below the exhaust port, | |||
the hottest point of the engine. | |||
That's right. The crankcases are in part liquid-cooled, but more important, | |||
the coolant, having been drawn out of the radiator by the pump, goes pretty | |||
directly to the area in greatest need of cooling. That makes more sense than | |||
running the coolest water into the cylinder heads preheating it before it | |||
reaches the exhaust area. Coolant then passes up through the cylinder, through | |||
the head and to the top of the single-core radiator. No auxiliary cooling fan | |||
clutters the RG; it is, after all, built to be in motion. | |||
The six-speed transmission operates through a seven-plate wet clutch driven | |||
via a helical gear off the right side of the crank. The upper five ratios, | |||
grouped fairly close together, help the rider to cope with the narrow 2000-rpm | |||
powerband. In practice, first gear is a starting gear; it takes some over | |||
revving to keep the engine pulling strong on the first/second break. A quick | |||
note here to you road ruffians make sure your Gamma is far ahead of the | |||
pack if your personal road has a first-gear hairpin. Otherwise, some pursuing | |||
rider latched to you like a bad odor will snake past on the exit when it's time | |||
to shift. | |||
You kick to start the Gamma. That's okay; when was the last time a serious | |||
racer pushed a button on the line? Our Gamma had the usual warning lights with a | |||
cute extra, the You Are Exceeding The National Speed Limit In Japan light. Our | |||
RG was a domestic (Japan only) model, and it conformed to Japanese Vehicle Code | |||
regulations. Motor vehicles in Japan must have little lights that flare up and | |||
stay lit any time offenders exceed 80 kph (50 mph) with their vehicles. | |||
By our reckoning, we had the Too Fast (Too Fun) light operating on the same | |||
schedule as, oh well, the spark plugs. | |||
This is the motorcycle for the few, the proud, the crazy. Which means that | |||
Suzuki could sell a handful of these bikes in the United Statesif they were EPA | |||
legal, and they're not. Yes, we know about catalytic converters for these | |||
things, and yes, it would be wonderful as, say, a 400. We love it as a 250, | |||
heaven knows, but still, folks, even as a 400 the Gamma would be an expensive | |||
toy, misunderstood and unwanted in Peoria. The narrow handlebars and | |||
high-mounted footpegs conspire with the firm seat to have you planning for your | |||
second stop almost before you finish your first one. Size for size, the Gamma | |||
makes a Phantom jet seem parsimonious. The RG swills at 35 mpg, so your sore | |||
butt will be out of the saddle in 120 miles. You'll either be pumping gas or | |||
walking. We recommend a hip flask for extra CCI oil because the RG empties its | |||
two-stroke oil tank every other gas stop. | |||
Forget touring considerations. The 250 Gamma is too direct, too connected | |||
with the pavement for that. Like a race bike, it gives its rider access to every | |||
capability in the motorcycle book of operations. The bike/rider communication is | |||
instantaneous, without the filtering and deadening qualities produced by | |||
excessive weight, slow steering, spongy suspension and soft braking. The Gamma | |||
turns, stops, responds; no delays, no questions. And you better be good without | |||
question, too. The RG-Gamma prefers smooth, sure guidance from its rider. If you | |||
get sloppy and don't know where you're going, not only will your cornering lines | |||
become haphazard, you'll have a hell of a time keeping the engine operating in | |||
its 2000-rpm window. | |||
Sure, the Gamma will work as a Saturday-cruise-to-the-beach special, and be | |||
wasted doing so. In the month we've spent with the RG, it's happier threatening | |||
life, limb and license. No, it's not unsafe; quite to the contrary, it'll get | |||
you out of trouble as fast as you get yourself into it. Some motorcycles are fun | |||
to ride fast, othersbetter yetare willing accomplices to misbehavior, and | |||
still othersbest of all are almost bonafide perpetrators themselves. | |||
Suzuki has done the responsible thing, Law and Order wise, mind you. They've | |||
kept the Gamma and its little EPA problem out of the United States. Yeah, and | |||
succeeded in making the few and the proud even crazier. | |||
Source Cycle 1984 | |||
{| class="wikitable" | |||
|- | |||
!Model. | |||
|Suzuki RG 250 Gamma | |||
|- | |||
!Year | |||
|1983 | |||
|- | |||
!Engine Type | |||
|Two stroke, parallel twin, reed valve | |||
|- | |||
!Displacement | |||
|247 cc / 15.1 cu in | |||
|- | |||
!Bore X Stroke | |||
|54 x 54 mm | |||
|- | |||
!Compression | |||
|7.4 :1 | |||
|- | |||
!Cooling System | |||
|Liquid cooled | |||
|- | |||
!Induction | |||
|2 x Mikuni VM28SS flat side carburetors | |||
|- | |||
!Ignition | |||
|Pointless Electrical Ignition | |||
|- | |||
!Battery | |||
|12V, 5Ah | |||
|- | |||
!Starting | |||
|Kick | |||
|- | |||
!Max Power | |||
|32.8 kW / 45 hp @ 8500 rpm | |||
|- | |||
!Max Torque | |||
|37 Nm / 3.8 kgf-m / 27.3 lb-ft @ 8000 rpm | |||
|- | |||
!Clutch | |||
|Wet, multi-plate | |||
|- | |||
!Transmission | |||
|6 Speed, constant mesh | |||
|- | |||
!Final Drive | |||
|Chain, #520, 110 links, O-ring sealed | |||
|- | |||
!Front Suspension | |||
|Telescopic fork, coil spring, oil dampened with anti-dive | |||
|- | |||
!Front Wheel Travel | |||
|130 mm / 5.1 in | |||
|- | |||
!Rear Suspension | |||
|Full Floater, mono-shock, gas/oil damped, spring preload fully adjustable | |||
|- | |||
!Rear Wheel Travel | |||
|122 mm / 4.8 in | |||
|- | |||
!Front Brakes | |||
|2 x 260 mm Discs ,1 piston caliper | |||
|- | |||
!Rear Brakes | |||
|Single 210 mm disc, 1 piston caliper | |||
|- | |||
!Front Tire | |||
|100/90-16 | |||
|- | |||
!Rear Tire | |||
|100/80-18 | |||
|- | |||
!Rake | |||
|24.7o | |||
|- | |||
!Trail | |||
|102 mm / 4.0 in | |||
|- | |||
!Dimensions | |||
|Length: 2050 mm / 80.7 in Width: 685 mm / 27.0 in Height: 1220 mm / 48.0 in | |||
|- | |||
!Wheelbase | |||
|1385 mm / 54.5 in | |||
|- | |||
!Ground Clearance | |||
|155 mm / 6.1 in | |||
|- | |||
!Seat Height | |||
|785 mm / 30.9 in | |||
|- | |||
!Dry Weight | |||
|131 kg / 289 lbs | |||
|- | |||
!Fuel Capacity | |||
|17 Liters / 4.5 US gal / 3.7 Imp gal | |||
|- | |||
!Oil Capacity | |||
|1.2 Liters / 1.3 US qt / 1.1 Imp qt | |||
|- | |||
!Consumption Average | |||
|6.6 L/100 km / 15.2 km/l / 35.7 US mpg / 42.9 Imp mpg | |||
|- | |||
!Standing ¼ Mile | |||
|14.4 sec / 145 km/h / 90 mph | |||
|} | |||
[[Category:Suzuki motorcycles]] |