.jpg)
.png)
.jpg)
.png)
.png)
.png)
Welcome to the 1970 Yamaha CT1B Forum. Feel free to post anything related to this model in the category. The factory Yamaha color was called "Candy Green". The USA vin range was: CT1-010101 to 031460. 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.
(Bike/photo Courtesy of Kurt Flash)
1970 Yamaha CT1B Specifications
Model 1970 Yamaha CT1B
Dimensions:
Overall Length 78 In. / 1,980MM
Overall Width 35.8 In. / 910MM
Overall Height 43.7 In. / 1,110MM
Wheelbase 50.8 In. / 1,290MM
Min. Ground Clearance 9.4 In. / 240MM
Weight:
Gross 232 Lbs. / 105Kg
Net 214 Lbs. / 97Kg
Performance:
Max, Speed 65 MPH / 105Km/h +
Fuel Consumption 117 MPG @ 31 MPH / 50Km @ 50Km/h
(On paved level roads)
Climbing Ability 32 Degree
Min. Turning Radius 74.8 In. / 1,900MM
Braking Distance 49 Ft. @ 31 MPH (15M @ 50Km/h)
Engine:
Model CT1
Type 2 Stroke, Gasoline
Lubricating System Separate (Yamaha Autolube)
Cylinder Single, forward inclined 5 Port
Displacement 10.43 cu. in. (171cc)
Bore X Stroke 2.598 X 1.969 In. (66 X 50MM)
Compression Ratio 6.75:1
Max Power 15.6 BHP/7,000 RPM
Max Torque 11.9 Ft.-Lbs/1.65 Kg-m @ 5,500 RPM
Piston Skirt Clearance .0016 - .0018 In. / 0.40 - 0.45MM
Starting System Primary-Coupled Kick
Ignition Timing B.T.D.C 1.8MM +/- .1MM
NGK Spark Plug & Gap B-8E 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 .30UF
Carburetor:
Type VM24SH
Main Jet # 150
Jet Needle 4D3-3
Air Jet -
Needle Jet N-8
Cut Away 2.0
Pilot Jet (#) 30
Air Screw (turns out) 1 1/2
Starter Jet (#) 40
Float Level 25.5MM
Intake:
Air Cleaner Wet, Foam Rubber
Transmission:
Clutch Wet, Multiple Disk
Primary reduction system Helical Gear
Primary reduction ratio 3.894 / (74/19) Teeth
Trans Oil Capacity .78 Qts
Gear Box:
Type Constant Mesh, 5 Speed Forward
1st Gear teeth & Ratio 3.182 (35/11) 34.85
2nd Gear teeth & Ratio 2.000 (30/15) 21.90
3rd Gear teeth & Ratio 1.368 (26/19) 14.99
4th Gear teeth & Ratio 1.000 (23/23) 10.93
5th Gear teeth & Ratio 0.800 (20/25) 8.76
Secondary reduction system Chain
Secondary reduction ratio 2.812 (45/16)
Chassis:
Frame Tubular-Double Loop
Front Suspension System Front Telescopic fork
Rear Suspension System Swinging Arm
Fork Oil Capacity 150cc (5.1 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 Degrees
Trail 4.8 In. / 123MM
Braking System:
Type of brake Internal Expansion
Front Operation System Right hand operation
Rear Operation System Right foot operation
Tire Size:
Front 3.25 - 18 - 4PR Trials Universal
Rear 3.50 - 18 - 4PR Trials Universal
Front Tire Pressure 14 P.S.I
Rear Tire Pressure 17 P.S.I
Oil Pump:
Adjustment Stroke Min 0.20 - 0.25 MM
Adjustment Stroke Max 1.85 - 2.05 MM
Dynamo:
Model F130-06
Manufacturer Hitachi Ltd.
Battery:
Model MV1-6
Manufacturer Furukawa Battery
Capacity 6V 2AH
Lighting:
Head Light 6V 25W/25W
Tail Light 6V 5.3W
Stop Light 6V 17W
Meter Light 6V 3W X 2
High Beam Indicator Light 6V 1.5W
Tanks:
Gasoline Tank Capacity 1.9 Gallons
Oil Tank Capacity 1.3 Quarts
Chain:
Tension (Up & down free play) 20MM (25/32)
The 1970 Yamaha CT1B Rider's Manual is Located: CLICK HERE
The 1970 Yamaha CT1B Service Manual is Located: CLICK HERE
The 1969-1971 Yamaha AT/CT Combined Service Manual is Located: CLICK HERE
The 1969-1971 Yamaha AT/CT Parts Manual is Located: CLICK HERE
The 1970 Yamaha CT1B Advertisement #1 is Located: CLICK HERE
The 1970 Yamaha CT1B Article #1 is Located: CLICK HERE
The 1970 Yamaha CT1B Article #2 is Located: CLICK HERE
The 1970 Yamaha CT1B Article #3 is Located: CLICK HERE
The 1970 Yamaha CT1B Article #4 is Located: CLICK HERE
The 1970 Yamaha CT1B Article #5 is Located: CLICK HERE
The 1969-1971 Yamaha Autolube Adjustment & Color Codes are Located: CLICK HERE
The USA 1970 Yamaha CT1B Brochure is Located: CLICK HERE
The Canada 1970 Yamaha CT1B Brochure is Located: CLICK HERE
The 1970 Yamaha CT1-B Crankshaft Data 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 1970 Cycle Buyers Guide is Located: CLICK HERE
The 1970 Yamaha CT1-B Line-Up Advertisement # 2 is Located: CLICK HERE
The 1970 Yamaha CT1B Store is Located: CLICK HERE
I've been enjoying your site but you can imagine my surprise to find my 1970 CT1 pictured with the girl from down the street as the cover shot for the CT1 spec sheet! Pic taken on my front lawn. kurt@trailrider.com
Devin these model specific posts with all the associated links are awesome!
Thank you so much for the effort you put into them all.