Greg Marsh Enterprises

When it absolutely must be done right and with integrity, you need Greg Marsh Enterprises. Our motto, promise, mission, and ethic is: Satisfaction Guaranteed!

Home

Request More Info

Contact Us!

Triumph Home

Norton Home

Fasteners Database

Parts Database

Parts For Sale
Updated 06/09/19

A Few Pictures

Greg's Fun

Building a Mobile
Motorcycle Table
Updated 6/30/2018


Chain Helper
Updated 06/14/19

Wiring Helper
Updated 06/29/19

Battery/Oil Pressure
Monitor
Updated 9/2/18


Tri-Spark Products

Restoration Service

AMAL Carbs for Sale

AMAL Float Height

AMAL Tickler Conversion

Welcome to the British Motorcycle Wiring Helper


Most Vintage British Motorcycles used wiring harnesses and components from Lucas. Therefore, the wire colors are more or less consistent across brands. The table below covers most wire colors used and attempts to say how they were used. Where there are known differences from the standards, those differences are mentioned in the notes column. You can sort by any of the columns - just click on the header. If you'd like to see how I wire a Norton Commando, look here.

Wire Color Stripe Color Color Code Where Used Notes Examples
Black B Ground on Negative Ground Machines Most machines are positive ground and have no black wires. However, some harnesses (probably after-market) used black instead of red!

On some Triumphs, the horn to ground was Black.
Color Code: B
Black B PODtronics Negative Output Color Code: B
Black Red BR Contact Breaker to Center Cylinder's Coil, Triples Color Code: BR
Black White BW Contact Breaker to Timing Side Cylinder's Coil, Twins/Triples On singles, this is the Contact Breaker to Coil wire. Color Code: BW
Black Yellow BY Contact Breaker to Drive Side Cylinder's Coil, Twins/Triples Color Code: BY
Green G Dynamo Field Only on Magneto machines Color Code: G
Green Black GB Stator Low Output (RM19), One Leg (RM24) Color Code: GB
Green Red GR Lefthand Turn Signal Color Code: GR
Green While GW Righthand Turn Signal Color Code: GW
Green Yellow GY Stator High Output (RM19), One Side (RM21), One Leg (RM24) On Norton, also goes to the Warning Light Assimlator Color Code: GY
Light Green Brown LGN Turn Signal (Direction) Switch (Handlebar) common to Flasher Unit Color Code: LGN
Brown N Stop Light Color Code: N
Brown Black NB Horn button to horn (See PB Below) Triumph "usually" used this for the horn. Some used PB Color Code: NB
Brown Green NG Taillight, Pilot Light, Speedo & Tach Illumination Color Code: NG
Brown Blue NU Battery to Ignition Switch if no Ammeter or Battery to Ammeter and see NW Color Code: NU
Brown White NW Ammeter to Ignition Switch I use 14 gauge wire for this and NU Color Code: NW
Purple Black PB Horn button to horn (See NB Above) As far as I know, this color was always used on Norton Color Code: PB
Red R Ground on Positive Ground Machines Some harnesses replaced this with black, but that is not common. Color Code: R
Red R PODtronics Positive Output Color Code: R
Red Green RG Oil Pressure Switch to Oil Pressure Indicator (Red) Triumph before KE00001, after see WN Color Code: RG
Blue U Light Switch (Headlight) to Dip Switch (Handlebar) Color Code: U
Blue Red UR Dip Switch (Handlebar) to Dip (Low) Beam Color Code: UR
Blue White UW Dip Switch (Handlebar) to Main (High) Beam Color Code: UW
Blue Yellow UY Ignition Switch to Headlight Switch Color Code: UY
White W Ignition Switch to Coils and other circuits on when key in run position or run+lighting position. Color Code: W
White Black WB Contact Breaker (Distributor) to Ignition Coil Only on Magneto machines. Note: The Norton MKIII workshop manual wiring diagram incorrectly shows this instead of Black/White as the timing side contact breaker to coil wire. Color Code: WB
While Green WG Stator Common (RM19 & RM24), One Side (RM21) On Norton MKIII this also goes to the Warning Light Assimulator Color Code: WG
White Brown WN Warning Light Assimulator to Charging Indicator (Red) Norton Color Code: WN
White Brown WN Oil Pressure Switch to Oil Pressure Indicator (Red) Triumph from KE00001 on Color Code: WN
White Purple WP Ballast Resistor to Ignition Coils Norton Color Code: WP
White Red WR Starter Switch (Handlebar) to Starter Selenoid Norton MKIII, Triumph T160 Color Code: WR
White Blue WU Under tank junction to ballast resistor Norton, See WY Color Code: WU
White Yellow WY Engine Kill (Handlebar) Triumph Twins/Triples when no balast resistor is used: To coils.

Norton Commando, Pre-MKIII: To junction under tank where it connects to the White/Blue which connects to the balast resistor.

Norton Commando MKIII: To the balast resistor.
Color Code: WY
Yellow Y PODtronics single or three phase input from stator Color Code: Y
Yellow Y Dynamo Output Only on Magneto machines Color Code: Y

Burlen, the parent of the AMAL Carb Company    The AMAL Carb Company    Tri-Spark, inovative electrical products for the Vintage British Motorcycle    Wassell, the 70+ year old suppliers of British Motorcycle parts    Central Wheel Company, the 120+ old suppliers of spokes and rims
Copyright © 2003-2019 Greg Marsh Enterprises
 8116 Arlington Blvd. #171, Falls Church, VA 22042, (703) 200-4025