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1975 Yamaha RD350B

This is my second motorcycle, which I bought new from a Yamaha dealer in Iowa Park, Texas during my senior year in high school. I went on my first real motorcycle road trip on this one, traveling with my older brother to Mason, Del Rio, Ciudad Acuna, Big Bend National Park, Pecos, and Guadalupe Mountains National Park.

  • 350 cc two-stroke, two-cylinder engine
  • Purchased new in 1975 in Iowa Park, Texas
  • A really fast bike when running well
  • Used for everyday transportation, college, and my first-ever long road trip
1975 Yamaha RD350B
Working on my 1975 Yamaha RD350B in the back yard of my brother's house on Mission Ridge in Austin, Texas, sometime in the late 1970s. Note the cool sissy bar with my shirt hanging on it. I appear to be doing something with the front disk caliper and instrument cluster. The right turn signal is missing, the tachometer is dangling, and perhaps the brake lever is bent. I did drop this bike once on a bitterly cold ride from Austin to Iowa Park when I hit a sandy patch on the highway near Jacksboro. This could have been the aftermath.


Click on images below for full-resolution version (opens in new window)

Yamaha 350 brochure p. 1

Original sales brochure (page 1)

Yamaha 350 brochure p. 2

Original sales brochure (page 2)

Yamaha 350 brochure p. 3 Original sales brochure (page 3)
Yamaha 350 brochure p. 4 Original sales brochure (page 4)


Max. speed range 100 mph
Min. turning radius 90.6 in.
Min. braking distance 46 ft. @ 31 mph

Engine and Transmission

Type 2-stroke, Torque Induction, Parallel Twin
Displacement 347 cc (21.18 cu. in.)
Bore & Stroke 2.520 x 2.126 in. (64 mm x 54 mm)
Compression ratio 6.6:1
Power 30.5 bhp @ 6,750 rpm
Max. torque 28.0 ft.-lb. @ 7,000 rpm
Carburetor Twin Mikuni VM-28
Lubrication system Autolube
Starting system Primary kick starter
Ignition system Battery
Transmission 6-speed gearbox
Primary ratio 2.869:1
Final drive ratio 2.666:1
Gears 1st: 2.571; 2nd: 1.777; 3rd: 1.318; 4th: 1.040; 5th: 0.888; 6th: 0.785
Transmission oil SAE 10W/30SC, 1500 cc


Overall length 80.3 in.
Overall width 32.9 in.
Overall height 43.7 in.
Wheelbase 52.0 in.
Min. ground clearance 6.1 in.

Fuel Tank

Capacity 3.2 U.S. gal.

Oil Tank

Capacity 2.1 U.S. qts.


Front 3.00-18-4PR; radius 12 in., or (2 x 3.0 + 13)/2
Rear 3.50-18-4PR; radius 12.5 in., or (2 x 3.5 + 18)/2

Created 20110923; Updated 20140216