# What is a crankshaft fillet?

## What is a crankshaft fillet?

A fillet is a radius created in the transition from the rod or main journal to the vertical portion of the crankshaft. The radius improves crankshaft strength but requires a slightly narrower bearing compared to stock production bearings. One small point that is often overlooked is connecting rod bearing width.

## What is crank pin bearing?

A crankpin is the part of the crank of a crankshaft to which the connecting rod is attached. Connecting rods typically have two-piece crankpin bearings for connecting the lower end of the rod to a crankpin of a crankshaft.

Definitions. rod length (distance between piston pin and crank pin) crank radius (distance between crank pin and crank center, i.e. half stroke)

What is crank pin effort?

Crank effort is the net effort applied at the crank pin perpendicular to the crank which gives the required turning moment on the crank shaft. The component of force acting along connecting rod perpendicular to the crank is known as crank-pin effort.

### Where is my crank position?

The Math / Science

1. x = piston position.
2. r = crank radius (distance between crank pin and crank center)
3. A = crank angle (from cylinder bore centerline at TDC)
4. l = rod length (distance between piston pin and crank pin)

### What is a crank pin journal?

A crankpin journal is a precision ground surface that provides a rotating pivot point to attach the connecting rod to the crankshaft. The throw is the measurement from the center of the crankshaft to the center of the crankpin journal, which is used to determine the stroke of an engine.

How do you match connecting rods and caps?

Try each cap on each rod until you find the one that fits right. You’ll probably have to torque them to make sure. When they’re right, you won’t feel the parting line between cap and rod, both in the bore and on the sides (thrust surface).