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General Specifications for the RL250 can vary from publication to publication. Most of the differences seem to be just a mistake or a typographical error representing the same value in both metric and our decimal system. For example, the Suzuki Service Manual states that the RL250 has a 1.63 meter turning radius (in Japan, I guess) and the US RL250 has a 53 foot turning radius. Maybe that's why the "RL250 doesn't turn well". That one's easy since someone just left the decimal point out. It should be 5.3 feet. On the other hand, the 1975 RL250M Owners Manual states the Maximum Horsepower is "1.8 HP at 6,000 rpm". There's that missing decimal point.

Granted, most of the differences are insignificant but if an RL250 owner only has one reference, there would be an unsolvable question about a specification's accuracy. Four resources have been pulled together here; the original Suzuki Service Manual - published June 1974, 1974 RL250L Owner's Manual - published April 1974, 1975 RL250M Owner's Manual - published August 1974, Clymer Suzuki 125-400 Singles 1964-1981 Service, Repair, Maintenance manual - 10th printing November 1996.

An 'x' just means that the publication didn't have a value or reference for the category. Anything highlighted in red is an obvious typo. There are a couple of odd things, like '18 ps' from the Suzuki Service Manual instead of '18 hp' (horsepower), that is entered as found in the publication. Remember that the 'differences' in the 1974 RL250L and 1975 RL250M are not necessarily by model year. I discuss my impressions of how and when changes were made here.

The RL250 ignition system is known as P.E.I., or Pointless Electronic Ignition. In spite of this very unfortunate name, the system has proven itself to be almost trouble-free. Being electronic, the ignition advance is built-in to the CD Ignition Unit and it is non-adjustable. Only one part number Ignition Unit is listed for the two model years. The differences in timing values given below are quite different and I don't know which is 'correct'. The timing is set by such a secure and simple method that, once accomplished, there is no real need to worry, check, or tinker with it. It's as 'set and forget' as anything I've ever dealt with. 

The fuel-oil mixture shown below was, of course, pretty standard fare for the mid 70s. Motor oil or automobile automatic transmission fluid was specified for different tasks because there just wasn't motorcycle specific lubricants readily available. Today, an owner would need to be prepared to take some verbal abuse for the cloud of smoke that could be tracked from space emitted by his RL250 using a 20:1 mixture of motor oil and gasoline. A modern semi-synthetic in a mixture of 60:1 will do wonders for your engine, the environment, and  interpersonal relationships with your fellow riders. Speaking of modern lubricants, there is a short discussion of transmission lubricants here and fork oils here.   

                                                    Clymer                       Suzuki Service Manual                        1974 Owner's Manual                        1975 Owner's Manual

Dimensions

Overall Length                                80.1 in                                80.1 in                                             80.1 in                                             80.1 in

Overall Width                                33.5 in                                 33.5 in                                             33.5 in                                             33.5 in

Overall Height                                    x                                     44.5 in                                             44.5 in                                             44.5 in

Wheelbase                                     53.0 in                                 53.0 in                                             53.0 in                                             53.0 in

Ground Clearance                           11.4 in                                 11.4 in                                             11.4 in                                             11.4 in

Weight                                          199 lb                                  199 lb                                              119 lb                                               199 lb

 

Performance

Maximum speed                                x                             104-120 kph (65-70 mph)                                x                                                       x

 

Engine

Type                                2-Stroke Air-Cooled Gasoline    2-Stroke Air-Cooled Gasoline        2-Stroke Air-Cooled Gasoline               2-Stroke Air-Cooled Gasoline

Cylinder Arrangement                    Single                                    Single                                                  1                                                     1

Displacement                         15.0 cu in (246cc)                     246cc, 15.0 cu in                             246cc, 15.0 cu in                                246cc, 15.0 cu in

Bore x Stroke                        2.76x2.52 in (70x64mm)        2.76x2.52 in (70x64mm)                    70x64mm (2.76x2.52 in)                     70x64mm (2.76x2.52 in)

Compression Ratio                            6.7:1                                    6.7:1                                                6.7                                                    6.0

Maximum Horsepower              18 hp @ 6,000 rpm                18 ps @ 6,000 rpm                              18 hp @ 6,000 rpm                            1.8 hp @ 6,000 rpm

Maximum Torque                   16.6 ft-lb @ 4,500 rpm          16.6 ft-lb @ 4,500 rpm                        16.6 ft-lb @ 4,400 rpm                        16.6 ft-lb @ 4,500 rpm

Starter Type                                Primary Kick                        Primary Kick                                      Primary Kick                                     Primary Kick

Valve System                                      x                                  Piston valve                                      Piston valve                                      Piston valve

 

Fuel System

Carburetor                                     VM 28SH                                VM 28SH                                            VM 28SH                                           VM 28SH

Fuel Tank Capacity                  1.3 gal (5.0 liters)                    5 liters (1.3 gal)                          1.3 gal (5.0 liters) including              1.3 gal (5.0 liters) including

                                                                                                                                          1.5 US pint (0.7 liter) reserve          1.5 US pint (0.7 liter) reserve

Air Filter                                            x                          Wet polyurethane filter                        Wet polyurethane filter                    Wet polyurethane filter

 

Lubrication System

Engine                                    Gas-oil Mixture 20:1             Gas-oil Mixture 20:1                               Gas-oil Mixture 20:1                         Gas-oil Mixture 20:1

Transmission Oil Capacity            1.5 pint (700cc)                700cc (1.5 US pint)                                 700cc (1.5 US pint)                           850cc (1.8 US pint)

 

Ignition System

Type                                                P.E.I.                                P.E.I.                                                    P.E.I.                                               P.E.I.

Timing                                        21 @ 4,000 rpm                21 @ 4,000 rpm                                   14 @ 1,000 rpm                               14 @ 1,000 rpm

                                                                                                                                                   21 @ 6,000 rpm                               21 @ 6,000 rpm

Spark Plug Type                            B7ES NGK                          B-7ES NGK or                                         B-7ES NGK or                                    B-7ES NGK or

                                                                                     Nippon Denso W22ES                               Nippon Denso W22ES                        Nippon Denso W22ES

Transmission and Clutch

Clutch Type                                Wet multi-disk                  Wet multi-plate                                     Wet multi-plate                                Wet multi-plate

Transmission Type                  5-speed constant mesh        5-speed constant mesh                           5-speed constant mesh                      5-speed constant mesh

Transmission Gear Ratios             1st    2.41:1 (29/12)                   Same                                                    Same                                               Same

                                                2nd   1.80:1 (27/15)

                                                3rd    1.41:1 (24/17)

                                                4th    0.86:1 (19/22)

                                                5th    0.64:1 (16/25)

Primary Reduction Ratio                4.16:1 (75/18)                    75/18 = 4.166                                        4.166 (75/18)                                    4.235 (72/17)

Secondary Reduction Ratio            3.60:1 (54/15)                    54/15 = 3.600                                        3.600 (54/15)                                    3.600 (54/15)

Drive chain                                           x                            #428, 120 links                                       #428, 120 links                                   #428, 120 links

 

Suspension

Front                                         Telescopic Fork              Telescopic, Oil Damped               Hydraulically Damped telescopic fork    Telescopic fork with hydraulic damper

Rear                                           Swinging Arm               Swinging arm, oil damped                  Hydraulically damped swinging          Swinging arm with hydraulic damper

                                                                                                                                                         arm 5-way                                   5-way adjustable

Steering

Steering Angle                                    60                           60 (right and left)                                60 (right and left)                             60 (right and left)

Turning Radius                            64 in (1,630mm)                     53 ft (1.63 m)                                      5.3 ft (1.63 m)                                  5.3 ft (1.63 m)

Trail                                                   x                                 3.0 in (76mm)                                      3.0 in (76mm)                                   3.0 in (76mm)

Caster                                                x                                          63                                                    63                                                   63

 

Brake

Type                                               Drum                                         x                                                      x                                                       x

Front                                                 x                              Right Hand operated,                          Right Hand operated,                          Right Hand operated,

                                                                                         internal expanding                              internal expanding                               internal expanding

Rear                                                  x                              Right Foot operated,                          Right Foot operated,                           Right Foot operated,

                                                                                         internal expanding                              internal expanding                               internal expanding

Tires

Front                                                  x                                   2.75-21 4PR                               2.75-21 4PR Semi-knobby                    2.75-21-4PR, Trial universal

Rear                                                   x                                   4.00-18 4PR                                     4.00-18 4PR Trial                          4.00-18-4PR, Trial universal

 

 
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Last modified: 05/26/14