Motorcycle Crankshaft Rebuilding and Connecting Rod Replacement

Why Crankshaft Accuracy Matters

A typical single-cylinder two-stroke crankshaft consists of two crank webs, a crankpin, connecting rod, big-end bearing and thrust washers. These components must be assembled, aligned and trued to the manufacturer’s specifications.

Excessive crankshaft runout can cause vibration, accelerate bearing wear, reduce reliability and shorten engine life. Even a few thousandths of an inch of runout can be significant. At Ken OConnor Racing, we understand that precision crankshaft assembly and truing are essential to building a reliable, high-performance engine.

Our Crankshaft Rebuilding Process

Every crankshaft rebuilt by Ken OConnor Racing is carefully inspected, assembled and precision-trued in our in-house motorcycle machine shop.

We use purpose-built crankshaft assembly fixtures and precision measuring equipment to evaluate crankshaft runout, connecting rod alignment and overall assembly accuracy. Worn connecting rods, crankpins, big-end bearings and thrust washers are replaced as required using components appropriate for the application.

Each crankshaft is assembled and trued to the applicable manufacturer’s specifications. Completed assemblies undergo careful inspection before leaving our shop.

From vintage two-stroke motorcycles to modern dirt bikes, ATVs and high-performance engines, our goal is to deliver accurate, reliable crankshaft rebuilding for customers nationwide.