Electronic Ignitions for Triumph, BSA & Norton Motorcycles

Shop electronic ignition kits for classic British motorcycles, including twins, singles, triples, distributor singles and pre-unit magneto models. We stock Boyer Bransden, Pazon, Tri-Spark, Sparx and Wassell Vape systems, plus matching ignition coils.

The right kit depends on five things: your engine type (twin, single or triple), how your current ignition works (side points, distributor or magneto), your system voltage and earth polarity, your coils, and the condition of your battery and charging system. The guide below explains each one.

Why Convert from Points?

Lucas points ignitions use a mechanical auto-advance unit, which wears. They also need regular gap and timing adjustment, and their condensers fail. An electronic ignition replaces the points, condensers and mechanical advance with a magnetic trigger and an electronic module. Most kits advance the timing electronically (Pazon; Boyer Bransden). In practice, owners get more consistent timing, fewer adjustments and easier starting.

There’s one important trade-off: battery-and-coil electronic ignitions need good voltage. A magneto makes its own spark. Points will often still spark on a weak battery. But an electronic module needs a healthy battery and charging system to work properly (Tri-Spark FAQ; Sparx instructions (PDF)).

The Main Electronic Ignitions for Vintage British Motorcycles

Boyer Bransden (UK)

Boyer is the longest-established name in British bike electronic ignition. The Micro MKIII/MKIV is an analog system. It advances at a set rate from fully retarded to maximum advance as engine speed rises from zero to 4,000 rpm. It is designed to work with original or replacement coils, except on Triumph/BSA triples, which need three 6-volt coils (Boyer Micro MKIII data (PDF)). Boyer’s Micro-Digital uses a microprocessor and has idle stabilization. Its coil switching is programmed, so replacement coils should have a similar resistance to the originals (Bombar’s Beemers summary of Boyer data; Boyer fitting instructions).

Shop Boyer:

• Triumph & BSA twins
• Norton Atlas & Commando
• Triumph & BSA singles (B50, Victor, TR25W)
• Triumph & BSA triples (T150, X75, T160, A75)
• Distributor singles (Tiger Cub, T20, C15, B40)

Pazon Sure-Fire (New Zealand)

The Sure-Fire is a 12-volt wasted-spark system for 360° parallel twins. Its electronic advance is designed to perform well at low cranking speed and low supply voltage, and the module is protected against reverse battery connection. Coils must be wired in series. Pazon recommends two 6-volt Lucas-type coils, or one 12-volt dual-output coil with a primary resistance of 3–5 ohms. Coils below 3 ohms, including CDI-type coils, are not compatible (Pazon product page).

Shop Pazon: Sure-Fire PA2 for Triumph, BSA & Norton 500–850 twins

Tri-Spark (Australia)

The Tri-Spark Classic Twin is fully digital, and its electronics are built into the stator plate, so there’s no separate black box. It has an LED for static timing, idle stabilization, and anti-kickback starting logic, which helps protect electric-start mechanisms. It works on 12 volts with either positive or negative earth. Coil circuit resistance must be 3.0–5.0 ohms, and the kit reaches full advance at 3,500 rpm. Tri-Spark also makes triple systems and a magneto replacement kit for three-bolt-flange K2F/K1F/KVF engines (Tri-Spark magneto kit specifications; Tri-Spark FAQ and instructions; our Tri-Spark timing guide).

Shop Tri-Spark:

• Classic Twin for twins and singles
• Classic Twin with coils option
• Triples kit (T150, T160, A75)
• Triples kit, alternate version
• Magneto replacement kit, 12V

Sparx (UK, distributed by Tricor)

Sparx is a wasted-spark system for twins and singles that works on positive or negative earth with 6V or 12V coils. Sparx supplies 6V coils to help starting. Its advance curve runs from 600 rpm to 13° of full advance at 5,000 rpm. The instructions require a charging system that delivers 11–14 volts under load and a battery that holds at least 11 volts at a 5-amp load (Sparx fitting instructions (PDF)).

Shop Sparx: Sparx electronic ignition kit for twins and singles

Wassell Vape (Vape, Germany, distributed by Wassell)

The Vape 12V kit (06-1495) is for unit twins and singles with side points, and works on positive or negative earth. Its typical working advance is 10° at 2,500 rpm. It needs the frame as an electrical return, so rubber-mounted engines need a good earth strap. It can also be used inside a magneto replacement body. The Micro MK2 kit (06-1476) is mainly a 6V twin kit that can also run on 12V. It fits the Lucas K2FIH ignition housing, which makes it a common choice for pre-unit twins.

Shop Wassell Vape:

• Vape 12V kit
• Vape kit with twin coils
• Vape kit for singles with 12V coil
• Vape Micro MK2, 6V/12V

Magneto replacement housings

Pre-unit twins and other magneto engines have no points cavity in the timing cover. Their ignition must instead sit in a body that bolts where the magneto was. The genuine Lucas K2F housing for electronic conversion comes with leads, dummy pick-ups, seals, a shaft and a sealed bearing, and is designed for Vape internals. It’s also sold as a complete K2F housing with Vape kit. Alternatively, the Tri-Spark magneto replacement kit includes its own housing, ignition and dual-output coil.

Compare at a Glance

System	Engines covered in our range	Volts	Earth	Advance	Coil requirement	Notable features
Boyer Micro MKIII/IV	Twins, singles, triples, distributor singles	12V	Check kit	Analog, to 4,000 rpm	Original or similar; triples need 3 × 6V	Long track record; widest model coverage
Pazon Sure-Fire PA2	360° twins	12V	Both	Electronic	Series; ≥3 Ω (2 × 6V or 3–5 Ω dual)	Low-voltage and low-cranking performance; reverse-polarity protection
Tri-Spark Classic Twin	Twins, singles, triples, magneto kit	12V	Both	Digital, full at 3,500 rpm	3.0–5.0 Ω	No black box; LED static timing; anti-kickback
Sparx	Twins, singles	6V or 12V coils	Both	600–5,000 rpm, 13°	6V coils supplied	Needs 11–14 V charging
Wassell Vape 06-1495	Unit twins and singles with side points	12V	Both	About 10° at 2,500 rpm	Twin coils	Needs frame return / earth strap
Wassell Vape MK2 06-1476	Twins, K2FIH housing	6V or 12V	Check kit	Electronic	Per instructions	6V pre-unit option

Sources: manufacturer documents linked above. Always follow the instructions supplied with your kit.

How to Choose the Right Electronic Ignition

1. Engine type. Twin, single or triple? Twins also need a specific crank layout: most kits assume a 360° crank, and Tri-Spark offers a rotor modification for 270° and other offset cranks (Tri-Spark timing guide).
2. Where the ignition goes. On unit twins and many singles, it goes in the side points cavity in the timing cover. Some singles use a distributor, such as Tiger Cub, C15 and B40. Pre-unit twins, BSA A7/A10s and early Atlas models use a magneto, which needs a replacement housing.
3. Voltage. Most kits are 12-volt. If you want to keep a 6-volt system, look at the Vape Micro MK2 or a 6-volt Tri-Spark magneto kit (Tri-Spark blog).
4. Earth polarity. Many Triumph, BSA and Norton models are positive earth. Confirm that your kit supports your polarity, and wire it to the correct diagram.
5. Coils. Measure the primary resistance of your coils. Pazon and Tri-Spark need at least 3 ohms in the coil circuit. Boyer triples need three 6-volt coils. If you’re buying coils, pick a kit that includes coils, or choose matching ignition coils.
6. Battery and charging health. Check that the battery holds voltage under load and that the charging system and regulator deliver 13–14.5 volts. If they don’t, fix them first. A Podtronics regulator/rectifier is a common upgrade.
7. Electric start or kick start. On electric-start models (T160, late T140E/ES, Commando Mk3), a kit with anti-kickback logic or good low-voltage behavior protects the starter mechanism.
8. Originality. If you want the bike to look original, choose a system with no visible module, such as Tri-Spark, or plan to hide the module under the seat or side panel.

Installation and Usage Tips

Tips for all systems

• Disconnect the battery first. Wire to the correct positive-earth or negative-earth diagram, and double-check before reconnecting.
• Remove what’s no longer needed. Take out the points, the condensers, and the ballast resistor where one was fitted. Tri-Spark specifically says to disconnect and remove the original condenser pack (Tri-Spark FAQ).
• Remove or lock the mechanical advance unit. The electronic module now controls advance. Magneto replacement kits for pre-unit Triumphs need a solid (non-advancing) drive gear (Tri-Spark magneto kit).
• Rewire twin coils in series. On twin wasted-spark systems, the coils are usually rewired in series rather than parallel (BritSpark wiring guide).
• Use suppressed plug caps. Fit 5k-ohm suppressed caps, or resistor plugs where specified, to prevent interference with the module (Boyer Micro-Power (PDF); Sparx (PDF)).
• Route trigger wires carefully. Keep them away from the alternator’s AC wires. Leave a small loop, and secure the wires loosely to the frame so vibration doesn’t break them. This matters most on Norton Isolastic frames (Sparx (PDF)).
• Check the timing with a strobe. Find true TDC first. Then strobe-check at full advance, at the rpm the kit specifies.
• Fit a good earth strap. This is essential on rubber-mounted Norton Commandos (Vape listing).
• Clean every connector, switch and fuse holder. A small voltage drop that points tolerate can upset an electronic module; (NTNOA Boyer troubleshooting).

Boyer

• Timing is normally set with a strobe (EuroMotoElectrics product notes (PDF)).
• A low battery, a bad fuse, or one weak battery cell can cause misfires at idle or a spark when you switch on the lights. Check the battery before blaming the unit (NTNOA).
• On triples, use three 6-volt coils.

Pazon

• Don’t wire coils in parallel, and don’t use CDI or other low-resistance coils.
• Use the degree marks on the pickup plate for fine timing adjustment (Pazon).

Tri-Spark

• Set static timing with the built-in LED with the engine at the fully advanced position. Then confirm with a strobe.
• A battery is required, and lithium batteries are compatible. Keep the coil circuit at 3–5 ohms, and keep the rotor-to-stator air gap at about 2 mm (Tri-Spark).
• Watch our Tri-Spark timing video guide.

Sparx

• Fit the rotor loosely, then set the stator with its pillar bolts centered in the slots. Strobe at 5,000 rpm, then rotate the stator to align the timing marks.
• On machines with halogen lights or electric start, the charging system must keep up with the extra load (Sparx (PDF)).

Wassell Vape

• Use the frame as the electrical return and fit an earth strap on rubber-mounted engines.
• To add a kill switch on positive-earth bikes, break the black wire between the transistor box and the coil (British Bike Bits Vape listing).
• Commando wiring diagrams are available from BritSpark.

Troubleshooting

Our electronic ignition system diagnostics guide walks through common no-spark and misfire checks.

Related Electrical Categories

Electrical parts · Ignition coils · Charging system · Podtronics · Lucas electrical · British wiring · Electrex World · Electrical tools · Triumph electrical · BSA electrical · Norton electrical · Boyer Bransden · Tri-Spark · Sparx · Wassell · Tricor

Further Reading (external)

• Boyer Bransden – Micro MKIII data sheet (PDF)
• Boyer Bransden – fitting instructions
• Pazon – Sure-Fire twin 12V
• Pazon – Sure-Fire PA2 instructions (PDF)
• Tri-Spark – ignition systems
• Tri-Spark – instruction booklets and FAQ
• Sparx – fitting instructions (PDF)
• BritSpark – British motorcycle wiring diagrams
• NTNOA – Boyer troubleshooting

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