Suzuki T-250r
SUZUKI T-250R
CYCLE WORLD ROAD TEST
Suzuki's Latest 250 Roadster Is Bullet-proof. It Shares The 350's Crank Assembly. And Two-Up May Find Happiness Thereon.
IN 1965, the Suzuki X-6 was just about the fastest 250 two-stroke Twin to be had. CYCLE WORLD'S road test of the first X-6 in the October, 1965 issue showed a 15.3-sec. standing quarter-mile with a trap speed of 84 mph. An impressive 92-mph top speed was attained, a good speed for most 350 machines then available.
But the first X-6s had their drawbacks. The overall finish looked good for a while, but the paint had a tendency to fade and the chrome rusted in a short time. And the transmission was plagued by uncertain shifting and damaged gears. The clutch was a little jerky in operation and tended to heat up when used extensively. But they were quick!
For the 1969 model year Suzuki redesigned the X-6 and introduced the T-250 and T-350 series, each using the same crankcase assembly. The T-350 is different from the T-250 in its larger (61mm) bore, for an actual displacement of 315cc, and a higher final reduction ratio, but the machines are virtually identical in appearance. That should give a clue to the relative strength of the T-250’s engine components. The engine is as close to “bulletproof’ as any machine we’ve seen lately. Although a tad slower than the X-6, it’s a welcome trade-off for reliability.
The main differences in the engines of the X-6 and the T-250 lie in the cylinders and transmission. The T-250’s cylinders are of six-port design and use larger (26mm) carburetors as compared to the 24-mm units employed on the X-6. The transmission’s gear ratios were altered slightly and Keystone-type shifting dogs are now fitted for more positive “locking-in” of the gears. The Keystone-type dogs are cut at greater than a 90-degree angle, while the receiver slots in the gears are cut at less than a 90-degree angle by the same amount. This makes for a very positive shifting, with little chance of the machine’s jumping out of gear.
Other detail changes from the X-6 include slightly different crankcase die castings, with the oil pump now mounted on top of the right, rear side of the transmission cavity.
As far as most two-stroke Twins go, the T-250R is quite conventional. Induction is handled by piston-controlled ports which are simpler than a rotary-valve design, and the crankcases. which are split horizontally, make it an easy matter to repair the transmission without disturbing the crankshaft or pistons. Because the oil level in the transmission/clutch is generally below the seam, very little leakage occurs, and the number of necessary seams is reduced.
The T-250R’s transmission is well designed and executed. Both the mainshaft and the layshaft turn in ball or roller bearings, and the gears which rotate around the shafts are supported by needle bearings. All ratios are indirect, and shifting is accomplished by the use of cam slots in a rotating drum, as with other Suzuki models. A nice feature here is the incorporation ol a positive stop to keep the drum from turning too far during a vigorous shift, which could result in missing the next gear completely and winding up in a false neutral.
Another nice touch is the neutral brake, which applies a torce to the low gear pinion engaging with the low gear as it is being selected. This keeps the transmission from grinding, and ensures positive selection of low gear. With six speeds, the transmission shows the T-250R’s racing heritage and might be considered superfluous by some. But being able to snick the silky smooth lever in either direction to get just the right gear for the job is a feature appreciated by all our testers, and even more so when packing double in hilly country.
Strong power is available from the six-ported cylinders beginning at just under 4000 rpm and continuing right up to almost 8000 rpm. At higher speeds, vibration increases and power falls off rapidly, signaling the rider that it’s time to shift. The noise output certainly won’t tell him much, as the super silent exhausts and extraordinarily quiet (for a twostroke Twin) intake system are all but drowned out by the noise of the wind rushing by. Tractability at low engine speeds is quite good, but it is better to use the gearbox to keep the engine “on the boil” and the power coming.
Suzuki’s “Posi-Force” lubrication has been changed in name to CCI (crankcase inject), but not in operation. Oil from the remote tank is fed directly into the right and left main bearings and the cylinders by a variable-displacement, pistontype pump, which increases its output when the engine speed and throttle opening are increased. Oil which first lubricated the main bearings travels through the inside of the crankpins and lubricates the connecting rod big end needle bearings, and then joins with the oil which was injected into the cylinder areas to lubricate the pistons and the connecting rod small end (wrist pin) needle bearings.
The center main bearing, however, is lubricated by gravityfed oil from the transmission’s oil supply. A sediment trap below the bearing is capped with a drain plug (one of three under the engine) to allow the removal of trapped particles during an oil change.
Unlike the earlier X-6, the T-250’s clutch took repeated slipping at the drag strip without a whimper, and didn’t require adjustment during the entire test. The drive is always taken up smoothly without grabbing, and a cushion-drive mechanism between the rear sprocket and wheel adds more smoothness and extended chain and drive train component life. Primary drive is by helical gear, and is virtually silent in operation. We feel that the very slight power loss incurred by using helical-cut gears is well worth the silence that you wouldn't have if straight-cut gears had been used.
Large, virtually fade-free brakes are employed on the T-250R which complement the motorcycle’s outstanding performance. Even after several panic stops from 60 mph during our braking tests, they continued to drag the bike down from speed with good control and efficiency. Lever pressure is nominally low, giving the rider good “feel.”
Controls are free in operation and well placed. Brake and clutch levers fall readily to hand, and all thumb operated switches such as the turn signals, high and low beam switch, and the horn are operable without removing the hand from the handlebars. The foot pegs are placed fairly high up, which adds a feeling of raciness to the machine (rather like riding a horse with an English saddle), but they weren’t so high as to cause cramps for our six-footer. The foot controls are well placed in relation to the Ibotpegs, and the seat is reasonably comfortable for solo riding. Things get a little cramped with two aboard.
The handlebars are fairly high and wide, and give good control, but they force the rider to sit in a rather upright position, making him feel like a sail when traveling down the highway at a good clip. Also superfluous is the motocross-style crossbar; it isn’t needed, and hardly helps the appearance of the machine.
In their effort to give the T-250R a comfortable ride, Suzuki has gone to too soft a spring rate for the front forks. They settle fairly far down when a rider of average weight climbs aboard, and are downright close to bottoming out with two astride. We’d like to see somewhat stronger fork springs and heavier dampening qualities. The owner could improve the dampening by substituting a heavier weight oil in the forks, and by putting spacers on top of the fork springs to increase the spring rate somewhat.
The rear shocks are all too typically Japanese in their operation. That is, they lack sufficient rebound dampening and have a tendency to act like a pogo stick after hitting a bump. The spring rate is good, and provisions are made for gaining two harder settings by twisting a cam ring at the base of each shock absorber unit.
Despite a fairly short 51.8-in. wheelbase, handling qualities at speed are very good. On smooth roads, the machine can be hustled into a corner at a high rate of speed under complete control, until a bump causes the rear end to hop. Even though ground clearance is quite good with the machine unladen, with the soft suspension partially compressed, and the footpegsand stands nearer the ground, hanging the stands up can be a problem. The short wheelbase and well thought out steering geometry make the T-250R a sheer joy to ride in traffic. It’s as nimble a 250 as we’ve ridden.
Just as important as the steering geometry, the frame must be sturdy and correctly designed. Sturdy it is. Twin downtubes are welded to the steering head and feature thick gussets in this critical area. The tubes continued down under the engine and eventually terminate at points just in front of the top rear suspension mounts. From the top of the steering head rearwards come three tubes, a fairly large central tube and two smaller diameter tubes, one on either side. This design looks a little like the famed Norton Manx Featherbed frame, and is undoubtedly very strong. The swinging arm tubes also appear very strong and immune to Hexing.
Suzuki’s attention to detail is a strong point. Welds are nearly perfect, alloy castings are smooth and polished to a high luster, and thick chrome plating adds to the overall good appearance. Flawless paintwork on our test machine brought approving remarks wherever we went.
Nice touches abound everywhere. One is the vacuum-operated fuel shut-off valve which automatically closes when the engine is shut off. A reserve position is included, as is a prime position, which allows fuel to How into the carburetors without the engine running. A sediment bowl may be removed for cleaning periodically. Also appreciated was the inclusion of a grease fitting at the kickstarter pivot point. A better than average toolkit is located under the left-hand side panel, the removal of which exposes the battery and many of the electrics for servicing.
Mention should also be made of the electrical system, which performed exactly as it should; good lights, horn and easy starting were always available. Not so appreciated were the tires, which were quite hard in composition and didn’t provide the best grip we’ve seen in the wet.
Summing up, the T-250R is an excellent machine for the novice and expert alike. It will maintain a comfortable freeway cruising speed, losing its punch only above 70 mph, where adroit use of fifth and sixth gears is necessary. It will even serve admirably for two-up riding, although extended high speed cruising and grade climbing may prove a bit tedious for those used to the torque of a large displacement machine. Our pillion passengers rated the seating as quite comfortable with minimal cramping and good peg position for leg support.
The lightweight 250 is commonly regarded as an interim machine, a good substitute while you accumulate the cash and know-how to go on to bigger things. In this case, some of you may acquire the Suzuki T-250R and never go farther, finding it more than adequate to enjoy most of the pleasures in motorcycling.
SUZUKI T-250R
$699
SPECIFICATIONS
PERFORMANCE
