JIMS, sump grinding tool

Used to machine the pinion bearing seat in the right crankcase. Removes more material in less time and with greater precision than a conventional grinder. The JIMS grinder is guided on both sides of the pinion bearing seat. This additional support on the cam pinion side is achieved via a bolt in the base plate that precisely positions a drill bushing in which the grinder rotates. This base plate locates on the same crankcase pins as the cam cover. The position of this drill bushing is held within .0002" of the crankcase pins and within .0002" of the crankcase centreline.
Now, instead of supporting only from the left side with Timken bearings, which have a floating fit, the JIMS grinder uses an especially ground bearing sleeve to hold the left side of the grinding axle without movement. Both ends of the grinder are precisely supported on the same centre line as the flywheel assembly.
With this extremely rigid set-up, it is possible to drive the grinder with a low-speed drill motor without fear of vibration in the ground bearing seat. The JIMS grinder can still be driven with the conventional crank handle when desired. Use of JIMS tool 978341 (snap ring installer and remover) is recommended, especially on 90-99 crankcases.
Note: See 978412 for the replacement 1-3/4" outer diameter grinding head.


Specifications


Brand
Jims


Application
58-99 Big Twin crankcases (Excl. Twin Cam) (NU)


Material
Steel


Packaging weight
4.541 kg


HS Code
82055980


Motorcycle family
BIG TWIN, DYNA, FX, FXR, SOFTAIL, TOURING


Original name
JIMS, crankcase lap tool