Technical Articles
CARB O-RING SIZES: CB350, CB400, CB500, CB550
When rebuilding carbs on the old Honda fours with press-in main jets, you will often find that all the metal parts are fine after a good cleaning, and all that you really need to buy are new O-rings. Honda doesn’t sell the individual O-rings separately….
instead you have to buy a complete carb kit at $10 to $15 per carb. I found an industrial O-ring supplier who was willing to do small-volume counter sales, and was able to get new O-rings at about 50 cents per carb. Sizes are:
Main Jet: 1.2mm cross-section x 3.5 mm ID
Float Seat: 1.5 mm cross-section x 5 mm ID
Float Bowl Drain Screw: AS568-009 (7/32″ ID x 11/32″ OD)
———————————————————— CB550:
Shifter lever seal = inside diameter – 14mm, outside diameter – 24mm, depth – 5mm
And the one behind the sprocket = I.D – 33mm, O.D. – 57mm, depth – 7mm
Honda Wiring Colors
| Color | Use | Origin | Destination |
|---|---|---|---|
| Black | Switched Hot | Ignition Switch | Fuses |
| Black | Switched Hot | Ignition Switch | Handlebar Switch |
| Black | Switched Hot | Ignition Switch | Starter Switch |
| Black | Switched Hot | Ignition Switch | Voltage Regulator |
| Black/Brown | Fused Hot | Fuse Box | Oil Light |
| Black/Brown | Fused Hot | Fuse Box | Neutral Light |
| Black/Red | Fused Hot | Fuse Box | Starter Switch |
| Black/White | Ignition System Hot | Kill Switch | Coils |
| Blue/White | Switched Hot | Starter Switch | Dimmer Switch |
| Brown | Tail/Rear Light | Brown/White Ignition Switch | Brown Lead |
| Brown/Black | Fused Hot | Fuse Box | Brown/White Lead |
| Brown/White | Running Lights | Brown/White | Turn Signal Switch |
| Brown/White | Gauge Lights | Brown/White | Gauges |
| Brown/White | Taillight | Brown/White | Ignition Switch |
| Green | Ground | Load | Ground |
| Green/Red | Starter Safety Circuit | Starter Relay | Clutch Switch |
| Green/Yellow | Brake Light | Brake Light Switch | Brake Lamp |
| Gray | Hot Turn Signal | Flasher | Turn Signal Switch |
| Light Green | Horn Circuit | Horn Switch | Horn |
| Light Green/Red | Neutral Circuit | Neutral Switch | Neutral Light |
| Orange | Left Turn Signals | Turn Signal Switch | Left Turn Signal Lamp |
| Light Blue | Right Turn Signals | Turn Signal Switch | Right Turn Signal Lamp |
| Orange/White | Left Running Lights | Turn Signal Switch | Brown Lead |
| Light Blue/White | Right Running Lights | Turn Signal Switch | Brown Lead |
| Red | Hot | Battery | Ignition Switch |
| Red/White | Charging Lead | Rectifier | Battery |
| White | Lo Light | Dimmer Switch | Headlight |
| Blue | Hi Light | Dimmer Switch | Headlight |
| White/Green | Fused Hot: Turn Signal | Fuse Box | Flasher |
| White/Green | Fused Hot: Horn | Fuse Box | Horn |
| White/Green | Fused Hot: Brake Light | Fuse Box | Brake Light Switch |
| Yellow | Charging System | Stator | Rectifier |
| Yellow & Blue | Ignition | Points | Coils |
| Yellow/Red | Starter Circuit | Starter Switch | Starter Relay |