OFFRAMP OM33 Magneto Ignition for Harley Big Twin
Knucklehead, Panhead & Shovelhead (1936–1969)

Next-Generation High-Performance Magneto Ignition

Engineered for classic ignition systems. Built for a pure, uncompromised riding experience.

Modern Performance Magneto Ignition for Classic Big Twins

The OFFRAMP MM33 Magneto is designed specifically for 1936–1969 Harley Big Twin Knucklehead, Panhead & Shovelhead engines. While maintaining the mechanical simplicity of a traditional magneto, it introduces modern refinements focused on starting ease, installation flexibility, and long-term reliability.

Featuring a built-in automatic advance and retard system, the MM33 helps reduce kick-back during starting while delivering stable ignition performance once running—making it ideal for kick-start and higher-compression applications.

To accommodate different frame designs and visual preferences, the magneto supports multiple mounting orientations, allowing builders to fine-tune both function and appearance.

Each OFFRAMP Magneto is precision-assembled to order, ensuring consistent performance and dependable quality.

It is more than an ignition system—it is a refined expression of mechanical simplicity and modern reliability.

The separate drive and magneto head design enables installation without removing the front cylinder head. An adjustable height design allows flexible fitment without trimming cylinder head fins or modifying pushrod covers. An improved no-leak drive housing ensures clean and reliable operation. The magneto supports standard or out-to-side mounting options and is compatible with both battery-equipped and battery-free setups.

OFFRAMP MAGNETO features a 5-axis CNC-machined solid aluminum base,
precision-cut from a single billet of high-grade aluminum to achieve an ideal balance of structural strength, machining accuracy, and weight optimization.
All models are finished with an 8K mirror-polished surface, delivering long-term durability while maintaining a premium, high-end appearance without compromising mechanical performance.

Features a high-quality rare-earth magnet rotor combined with a dual-spring coil design to deliver stable and consistent ignition energy.
The contact point assembly utilizes a spherical contact design with an ultra wear-resistant rubbing block, reducing wear while improving ignition accuracy and service life.

Note:

• Some S&S engines use a reverse gear configuration. Please verify your engine setup before ordering, or contact us prior to purchase to confirm compatibility.

• Magneto Cap customization options:

• Multiple colors and material finishes available

• Selectable Kill Stud orientation

• Custom color options for Kill Stud orientation

• Production & lead time:

• All OFFRAMP magnetos are custom-built

• Standard lead time is within 1 week before shipping

• In case of raw material shortages, lead time may extend to 4–8 weeks

NOTE: No returns are accepted on magnetos as they are made-to-order.

Built on Tradition. Refined for Today.

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