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                1970 Yamaha DT1MX Specifications

            Model 1971 Yamaha DT1MX

   Dimensions:

Overall Length 81.1 In. / 2,060MM

Overall Width 35.0 In. / 890MM

Overall Height 44.5 In. / 1,130MM

Wheelbase 53.6 In. / 1,360MM

Min. Ground Clearance 9.6 In. / 245MM

    Weight:

Gross 256 Lbs.

Net 232 Lbs.

   Performance:

Max, Speed -

Fuel Consumption -

(On paved level roads)

Climbing Ability 35 Degree

Min. Turning Radius 82.6 In. / 2,100MM

Braking Distance 40 Ft. @ 30 MPH (12.5M @ 50Km/h)

   Engine:

Model DT1

Type 2 Stroke, Gasoline

Lubricating System Separate (Yamaha Autolube)

Cylinder Single, forward inclined 5 Port

Displacement 15 cu. in. (246cc)

Bore X Stroke 2.77 X 2.52 In. (70MM X 64MM)

Compression Ratio 8.2:1

Max Power 30 BHP/7,000 RPM

Max Torque 22.4 Ft.-Lbs @ 6,500 RPM                        

Piston Skirt Clearance .0018 - .0020 In. / 0.45 - 0.50MM                                         

Starting System Primary-Coupled Kick

Ignition Timing B.T.D.C 2.3 MM +/- .011 - 0.13 MM

NGK Spark Plug & Gap B-10E (N) 0.5-0.6 MM

Contact Break Point Gap 0.012 - 0.015 Inch / 0.30 - 0.40 MM

Volt Reg. Adjustment -

(Volts @ RPM - No load)

Cutout Relay Adjustment -

Condenser Capacity .22UF (Microfarad)

   Carburetor:

Type Mikuni VM30SH

Main Jet # 210 - 220

Jet Needle 5D5 - 4

Air Jet 0.5

Needle Jet 0 - 4

Cut Away 3.5

Pilot Jet (#) 80

Air Screw (turns out) 1 1/2

Starter Jet (#) 60

Float Level 25.5MM

  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) (21.888)

2nd Gear teeth & Ratio 1.650 (33/20) (16.051)

3rd Gear teeth & Ratio 1.261 (29/23) (12.267)

4th Gear teeth & Ratio 1.000 (26/26) (9.728)

5th Gear teeth & Ratio 0.793 (23/29) (7.714)

Secondary reduction system Chain

Secondary reduction ratio 3.143 (44/14)

  Chassis:

Frame Tubular-Double Loop

Front Suspension System Front Telescopic fork

Rear Suspension System Swinging Arm

Fork Oil Capacity 210cc (7.1 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 - 1BL

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

Oil Tank Capacity 1.7 Quarts

  Chain:

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

The 1971 Yamaha DT1E/DT1MX Rider's Manual is Located: CLICK HERE

The 1971 Yamaha DT1-MX Service Manual Supplement is Located: CLICK HERE

The 1968-1971 Yamaha DT1 Combined Service Manual is Located: CLICK HERE

The 1971 Yamaha DT1-MX Parts Manual 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 DT1-MX Parts Store is Located: CLICK HERE