Welcome to the 1970 Yamaha RT1 Forum. Feel free to post anything related to this model in the category. Anything new, will be added to this section. If you see any errors, please contact me privately. There were many errors, in the early Yamaha literature. I will make some error's of my own.
1970 Yamaha RT1 Specifications
Model 1970 Yamaha RT1
Dimensions:
Overall Length 82.7 In.
Overall Width 35.0 In.
Overall Height 45.7 In.
Wheelbase 54.7 In.
Min. Ground Clearance 10.0 In
Weight:
Gross -
Net 254 Lbs.
Performance:
Max, Speed 78 Mph
Fuel Consumption 82 MPG @ 37 MPH
(On paved level roads)
Climbing Ability 35 Degree
Min. Turning Radius 78.7
Braking Distance 49 Ft. @ 31 MPH
Engine:
Model RT1
Type 2 Stroke, Gasoline
Lubricating System Separate (Yamaha Autolube)
Cylinder Single, forward inclined 5 Port
Displacement 21.50 cu. in. (351cc)
Bore X Stroke (80MM X 70MM)
Compression Ratio 6.6:1
Max Power 30 BHP/6,000 RPM
Max Torque 26 Ft.-Lbs @ 5,500 RPM
Piston Skirt Clearance .0020 - .0022 In. / 0.50 - 0.55MM
Starting System Primary-Coupled Kick
Ignition Timing B.T.D.C 2.9 MM +/- .1MM
NGK Spark Plug & Gap B-9E / 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 VM32SH
Main Jet # 220
Jet Needle 6FC1 - 2
Air Jet -
Needle Jet 0 - 4
Cut Away 1.5
Pilot Jet (#) 30
Air Screw (turns out) 1 1/4
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 2.533 (38/15) (20.383)
2nd Gear teeth & Ratio 1.789 (34/19) (14.396)
3rd Gear teeth & Ratio 1.304 (30/23) (10.493)
4th Gear teeth & Ratio 1.000 (26/26) (8.047)
5th Gear teeth & Ratio 0.767 (23/30) (6.172)
Secondary reduction system Chain
Secondary reduction ratio 2.600 (39/15)
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 3.25 - 19 - 4PR Trials Universal
Rear 4.00 - 18 - 4PR Trials Universal
Front Tire Pressure 20 P.S.I
Rear Tire Pressure 24 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 MV1-6D
Manufacturer Nippon Battery
Capacity 6V 2AH
Lighting:
Head Light 6V 35W/35W
Tail Light 6V 5.5W
Stop Light 6V 17W
Meter Light 6V 3W X 2
High Beam Indicator Light 6V 1.5W
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 1970 Yamaha RT1 Rider's Manual is Located: CLICK HERE
The 1970 Yamaha RT1 Service Manual is Located: CLICK HERE
The 1970 Yamaha RT1 Service Manual is Located: CLICK HERE
The 1970 Yamaha RT1 Parts Manual is located: CLICK HERE
The 1969-1971 Yamaha Autolube adjustment and Color Codes are Located: CLICK HERE
The 1970 Yamaha RT1 Advertisement #1 is Located: CLICK HERE
The 1970 Yamaha RT1 Advertisement #2 is Located: CLICK HERE
The 1970 Yamaha Full Line Up Brochure is Located: CLICK HERE
The 1970 Yamaha Enduro Full Line Up Brochure is Located: CLICK HERE
The USA 1970 Yamaha RT1 Brochure is Located: CLICK HERE
The 1970 Yamaha RT1 Crankshaft Data is Located: CLICK HERE
The 1970 Yamaha RT1 Store is Located: CLICK HERE