Jims Tools

About Jims Tools

Jims Tools, known in the motorcycle world as JIMS USA, is an American manufacturer of performance parts and specialty service tools for Harley-Davidson motorcycles. Jims Tools traces its roots to 1967, when machinist Jim Thiessen, who had worked in the aerospace industry, began making hard-to-find, higher-quality American-made parts for riders who came to his shop. By the mid-to-late 1970s he had committed fully to V-Twin motorcycles, and the company now operates from Camarillo, California, with CNC machining capacity spread across several buildings.

A Reputation Built on Precision

Precision and consistency are central to the brand's identity. JIMS reports that it is ISO 9001:2015 certified, a quality-management standard intended to ensure repeatable, reliable manufacturing. Its catalog covers everything from Knucklehead-era bikes to modern Milwaukee-Eight models, so owners of vintage and late-model machines alike can find parts and tools made for their engines and gearboxes.

Transmissions and Gear Sets

Transmissions are the heart of the Jims Tools line. The company builds 5- and 6-speed gearboxes and sells many of them either as complete units or as upgrade kits. Its Jims Tools transmissions include straight-cut gear sets such as the Fat 6 Super Gear Kit, which uses aerospace-grade 9310 steel and gear teeth up to 53% wider than stock for added load capacity. Quick-shift ring technology is used to reduce the "clunk" that can come with hard shifts. These designs suit riders whose engines make far more torque than the original gearbox was built to handle.

Rebuild Kits for Manual Gearboxes

Not every gearbox needs a full upgrade. Sometimes a worn bearing, seal or bushing is the only problem. The Jims Tools manual transmission rebuild kits bundle the wear items needed to refresh a Harley gearbox, from bearings and seals to gasket sets. Matching the kit to your model year and transmission type matters, since the Big Twin 4-speed, 5-speed and 6-speed Cruise Drive units all differ.

Specialty Tools for Motorcycle Service

Jims Tools is just as well known for its service tools, which are precision machined to make demanding jobs more manageable. Items such as sprocket lockers, main drive gear installers, seal installers and bearing tools help technicians avoid damaging expensive components during assembly. Browsing the Jims Tools motorcycle selection is a good way to find tools and parts matched to specific Harley models.

Fork work is another area where the right tool matters. The Jims Tools suspension service fork range supports tasks like fork cap installation, where correct fit helps protect threads and seals.

What to Consider When Choosing

• Model year and engine family: Twin Cam, Milwaukee-Eight and earlier Big Twin parts are not interchangeable.
• Use case: Street riding, touring and racing place very different loads on a gearbox.
• Supporting tools: A good transmission stand and the correct seal and bearing installers make a rebuild much smoother.
• Related hardware: Gaskets, seals and hardware are often best replaced together with major components.