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                  1971 Yamaha RT1MX Specifications

            Model 1971 Yamaha RT1MX

   Dimensions:

Overall Length 82.3 In.

Overall Width 35.0 In.

Overall Height 46.7 In.

Wheelbase 55.1 In.

Min. Ground Clearance 10 In.

    Weight:

Gross -

Net 242 Lbs.

   Performance:

Max, Speed -

Fuel Consumption -

(On paved level roads)

Climbing Ability 35 Degree

Min. Turning Radius 78.7 In.

Braking Distance 50.5 Ft. @ 31 MPH

   Engine:

Model RT1

Type 2 Stroke, Gasoline

Lubricating System Separate (Yamaha Autolube)

Cylinder Single, forward inclined 5 Port

Displacement 21.4 cu. in. (351cc)

Bore X Stroke 2.77 X 2.52 In. (80MM X 70MM)

Compression Ratio 7.2:1

Max Power 36 BHP/6,500 RPM

Max Torque 28.7 Ft.-Lbs @ 6,500 RPM                        

Piston Skirt Clearance .0020 - .0022 In. / 0.50 - 0.55MM                                         

Starting System Primary-Coupled Kick

Ignition Timing B.T.D.C 3.4 MM +/- .1 MM

NGK Spark Plug & Gap B-9EN (N) 0.5-0.6 MM

Contact Break Point Gap 0.011 - 0.013 Inch / 0.30 - 0.35 MM

Volt Reg. Adjustment -

(Volts @ RPM - No load)

Cutout Relay Adjustment -

Condenser Capacity .22UF (Microfarad)

   Carburetor:

Type Mikuni VM34SH

Main Jet # 310

Jet Needle 6DH2 - 3

Air Jet -

Needle Jet P - 0

Cut Away 2.5

Pilot Jet (#) 60

Air Screw (turns out) 1 1/2

Starter Jet (#) 60

Float Level 8.5 MM

  Intake:

Air Cleaner Wet, Foam Rubber

   Transmission:

Clutch Wet, Multiple Disk

Primary reduction system Helical Gear

Primary reduction ratio 3.095 / (65/21) Teeth

Trans Oil Capacity 1.06 Qts / 1,000cc

   Gear Box:

Type Constant Mesh, 5 Speed Forward

1st Gear teeth & Ratio 2.250 (36/16) (18.11)

2nd Gear teeth & Ratio 1.650 (33/20) (13.28)

3rd Gear teeth & Ratio 1.261 (29/23) (10.15)

4th Gear teeth & Ratio 1.000 (26/26) (8.05)

5th Gear teeth & Ratio 0.793 (23/29) (6.38)

Secondary reduction system Chain

Secondary reduction ratio 2.933 (44/15)

  Chassis:

Frame Tubular-Double Loop

Front Suspension System Front Telescopic fork

Rear Suspension System Swinging Arm

Fork Oil Capacity 175cc (5.9 Oz.)

Front Cushion System Coil Spring / Oil Damper

Rear Cushion System Coil Spring / Oil Damper

  Steering System:

Steering Angle 49 Degrees both left & right

Caster 60.5 Degrees

Trail 5.12 In. / 130MM

  Braking System:

Type of brake Internal Expansion

Front Operation System Right hand operation

Rear Operation System Right foot operation

  Tire Size:

Front 2.75 - 21 - 4PR Knobby

Rear 4.00 - 18 - 4PR Knobby

Front Tire Pressure 13 P.S.I

Rear Tire Pressure 16 P.S.I

  Oil Pump:

Adjustment Stroke Min 0.20 - 0.25 MM

Adjustment Stroke Max 1.85 - 2.05 MM

  Dynamo:

Model FZA - 1A1L

Manufacturer Mitsubishi Elec.

  Battery:

Model -

Manufacturer -

Capacity -

 Lighting:

Head Light -

Tail Light -

Stop Light -

Meter Light -

High Beam Indicator Light -

  Tanks:

Gasoline Tank Capacity 2.5 Gallons (9.5 Liters)

Oil Tank Capacity 1.7 Quarts (1.6 Liters)

  Chain:

Tension (Up & down free play) 20MM (25/32)

The 1971 Yamaha RT1MX Service Manual Supplement is Located: CLICK HERE

The 1971 Yamaha RT1MX Combined Service Manual is Located: CLICK HERE

The 1971 Yamaha RT1B/RT1MX Rider's Manual is Located: CLICK HERE

The 1971 Yamaha RT1-MX Parts Manual supplement is located: CLICK HERE

The 1969-1971 Yamaha Autolube adjustment and Color Codes are Located: CLICK HERE

The 1971 Yamaha Full Line Up Brochure is Located: CLICK HERE

The 1971 Yamaha Motocross Full Line Up Brochure is Located: CLICK HERE

The 1971 Motorcycle & Trail Bike Handbook is located: CLICK HERE

The 1971 Yamaha RT1-MX Parts Store is Located: CLICK HERE