JIMS, crankcase lap tool

Get Perfect Crankcase Surfaces with the JIMS Crankcase Lap Tool

Achieve flawless crankcase mating surfaces quickly and affordably with the JIMS, crankcase lap tool. This essential tool ensures a tight, leak-free seal, saving you time and costly repairs down the road. Whether you're rebuilding or maintaining your engine, this tool makes the job smoother and more precise.

Features & Benefits of the JIMS, Crankcase Lap Tool

• Precision-ground lapping plates: Guarantees even surface contact for a perfect seal every time.
• Adjustable tension mechanism: Allows you to control pressure easily, preventing damage to delicate crankcase surfaces.
• Durable steel construction: Built to last through countless engine rebuilds without warping or wear.
• Compact and lightweight design: Fits comfortably in your hand, making it easy to use in tight engine bays.
• Compatible with most Harley-Davidson and custom V-twin engines: Versatile tool for a wide range of motorbikes.

Save money by avoiding expensive machine shop work—this tool lets you lap your crankcase surfaces at home with professional results. It’s a must-have for any serious motorbiker who values precision and reliability.

Limited stock alert: The JIMS, crankcase lap tool is in high demand among bike builders and mechanics. Don’t miss out on this affordable, game-changing tool that’s flying off the shelves.

Ready to upgrade your engine rebuild game? Add the JIMS, crankcase lap tool to your cart now and experience the difference of perfectly lapped crankcases every time!

Used to lap pinion bearing race in the right crankcase. Removes more material in less time but with greater accuracy than a conventional lap. The JIMS case lap is guided on both sides of the pinion bearing race. This additional support on the cam gear side of the bearing race is achieved by means of a bolt on the base plate that precisely locates a drill bushing in which the lap turns. This base plate is located on the same engine case pins as the cam cover. The positioning of this drill bushing is held within .0002" to the engine case pins and within .0002" of the case centerline. Now, instead of guiding only from the left side with Timken bearings, which are a floating fit, the JIMS case lap uses a special ground bearing sleeve to hold the left side of the lapping shaft without movement. Both ends of the lap are supported precisely in the same centerline as the flywheel assembly. With this extreme rigid arrangement it is possible to power the lap with a low speed drill motor without fear of chatter in the lapped bearing race. The JIMS lap can still be powered by the conventional hand crank when desired. It is recommended to use JIMS 978341 (snap ring installer & remover tool), especially on 90-99 crankcases. Note: See 978412 vor the replacement 1-3/4" O.D. lap head