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1978 YAMAHA YZ400 Parts & Accessories

Fits Your Machine

Displaying parts for your 1978 YAMAHA YZ400

Change or remove machine

See stock sizes for this machine

  • Front Tire:3.00x21
  • Rear Tire:4.50x18
  • Front Sprocket:14 Tooth
  • Rear Sprocket:50 Tooth
  • Chain:520x106
  • Spark Plug:B8EG
For reference only. Please consult your owner's manual to confirm manufacturer specs.
NGK Iridium Sparkplug$10.99
★★★★★Rated 4.89 out of five stars.
Tusk Tach/Hour Meter$22.99 to – $32.98
★★★★⯪Rated 4.57 out of five stars.
Tusk Wheel Bearing and Seal Kit$11.99
★★★★⯪Rated 4.65 out of five stars.
Primary Drive 520 ORH Gold X-Ring Chain$4.99 to – $72.99
★★★★★Rated 4.67 out of five stars.
Tusk 520 Gold X-Ring Chain$4.99 to – $73.99
★★★★★Rated 4.74 out of five stars.
Tusk Fork and Dust Seal Kit$29.99
★★★★⯪Rated 4.33 out of five stars.
All Balls Wheel Bearing Kit$14.92
★★★★⯪Rated 4.52 out of five stars.
Tusk 520 O-Ring Chain$4.99 to – $54.99
★★★★★Rated 4.80 out of five stars.
NGK G-Rated Sparkplug$6.99
★★★★★Rated 4.87 out of five stars.
Tusk Magnetic Drain Bolt$9.99
★★★★★Rated 4.73 out of five stars.
Tusk Traverse Pannier Bags$99.99
★★★★★Rated 4.83 out of five stars.
Tusk T-10 Aluminum 7/8" Handlebar$39.99
★★★★⯪Rated 4.45 out of five stars.
Primary Drive 520 ORM O-Ring Chain$4.99 to – $53.99
★★★★★Rated 4.76 out of five stars.
Tusk Aluminum Tire Iron$16.99
★★★★⯪Rated 4.64 out of five stars.
Tusk Low-Profile Magnetic Drain Bolt$9.99
★★★★⯪Rated 4.62 out of five stars.
ProTaper SE 7/8" Handlebar$84.99 to – $87.99
★★★★★Rated 4.80 out of five stars.
Motion Pro Clutch Lever$15.99
★★★★⯪Rated 4.58 out of five stars.
DID 520 Chain$3.95 to – $62.09
★★★★☆Rated 4.14 out of five stars.
Primary Drive 520 ORH X-Ring Chain$4.99 to – $63.99
★★★★⯪Rated 4.65 out of five stars.
RK 520 Chain$31.88
★★★★☆Rated 4.27 out of five stars.
Tusk Piston Ring Compressor$24.99
★★★★★Rated 5.00 out of five stars.
Tusk Skid Plate Foam$10.95 to – $11.95
★★★★⯪Rated 4.59 out of five stars.
Motion Pro Flywheel Puller$19.99
★★★★★Rated 4.84 out of five stars.
Tusk Universal Big Bar Clamp Kit$29.99
★★★★★Rated 4.67 out of five stars.
Tusk Universal Big Bar Clamp and Bar Kit$78.99 to – $188.30
★★★★⯪Rated 4.50 out of five stars.
Renthal Aluminum 7/8" Handlebar$102.34 to – $107.61
★★★★★Rated 4.83 out of five stars.
Pivot Works Steering Stem Bearing Kit$54.10
★★★★★Rated 4.81 out of five stars.
Tusk 2" Pivoting Bar Risers$49.99
★★★★★Rated 5.00 out of five stars.
Rox Speed FX 2" Handlebar Risers$96.88 to – $99.88
★★★★★Rated 4.84 out of five stars.
RK 520EXW Gold XW-RING Chain$8.99
★★★★★Rated 4.80 out of five stars.
Tusk Offset Bar Risers$46.99
★★★★★Rated 5.00 out of five stars.
Mika Metals Pro Series 7/8" Handlebars$77.88 to – $89.88
★★★★☆Rated 4.18 out of five stars.
Odi Podium 7/8" Handlebars$85.46
★★★★★Rated 5.00 out of five stars.
Mylers High Pressure Radiator Cap$17.99
★★★★★Rated 4.79 out of five stars.
Race Tech Fork Seals$69.99
★★★★★Rated 4.72 out of five stars.
Yamaha OEM Exhaust Hangers$15.59 to – $52.25
★★★★★Rated 5.00 out of five stars.
K & L Fork Seals$12.09
★★★★⯪Rated 4.66 out of five stars.
Tusk Float Bowl Wrench$6.99
★★★★★Rated 4.85 out of five stars.
Wiseco Piston Replacement Circlip$2.99
★★★★★Rated 4.86 out of five stars.
RK 520EXW XW-RING Chain$8.99
★★★★★Rated 4.69 out of five stars.
IMS Flightline Folding Shift Lever$54.55
★★★★⯪Rated 4.50 out of five stars.
Rox Speed FX Pro-Offset Elite Block Risers$89.88
★★★★★Rated 4.83 out of five stars.
Mika Metals Pro Series 7/8" Handlebars without Bar Pad$74.88
★☆☆☆☆Rated 1.00 out of five stars.
P3 Carbon Skid Plate Foam$12.95
★★★★⯪Rated 4.53 out of five stars.
Motion Pro T-6 Combo Lever$39.99
★★★★★Rated 4.88 out of five stars.
Motion Pro Pro Plug Socket$34.99
★★★★★Rated 4.80 out of five stars.
Tusk Piston Replacement Circlip$1.79
Rox Speed FX 3 1/2" Pivoting Handlebar Risers$110.88
★★★★★Rated 5.00 out of five stars.
Moose Racing Magnetic Drain Plug$19.95
★★★★★Rated 4.73 out of five stars.
Mika Metals Hybrid Series 7/8" Oversized Handlebars without Bar Pad$107.88
Mika Metals Hybrid Series 7/8" Oversized Handlebars$109.88 to – $117.88
★★★★★Rated 5.00 out of five stars.
Klutchbox Original Bar Pad$64.95
★★★★★Rated 4.80 out of five stars.
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