ProX Engine Connecting Rod

ProX Connecting Rods: Where OEM Engineering Meets Aftermarket Value

The connecting rod is one of the most stressed components in any engine. Engine connecting rods endure relentless compression and tension with every combustion cycle, making material quality and manufacturing precision absolutely non-negotiable. Few aftermarket brands have built their reputation as squarely on connecting rods as ProX Racing Parts — it is, as they put it, the core product line where they became famous.

ProX Connecting Rod Kits are manufactured in Japan by the same leading OEM factories that supply major motorcycle brands worldwide. In fact, ProX rods are produced using the same tooling and the same high-grade Japanese steel as the OEM parts they replace — delivering identical I-beam shape, dimensions, and geometry at a fraction of dealer pricing. OEM specifications and tolerances are meticulously maintained, ensuring a straightforward, drop-in installation with no guesswork.

Double-Forged Construction and Surface Engineering

What sets ProX connecting rods apart begins at the forging stage. Each rod is double-forged on dedicated per-part-number forgings, a process that dramatically increases tensile strength and dimensional consistency through improved grain flow. After forging, every rod is barrelled and shot-peened to remove surface imperfections — a critical step, since sharp edges and corners can develop into stress cracks that ultimately cause rod failure. This combination of double-forging and surface treatment produces a rod that is reliable under nearly any operating condition.

ProX also pays close attention to lubrication engineering. The big-end pins are precision-machined and heat-treated, and on four-stroke applications, the pins include dedicated oil canals to maximize lubrication flow. Oiling slots are precisely located in the rod itself for extra pin oiling, and OEM-style oiling pockets are duplicated on the thrust washers to minimize friction between the rod, washer, and crankshaft web.

Complete Kits — Including Plain Bearing Applications

Every ProX Connecting Rod Kit ships as a complete assembly: crankpin, big-end bearing, small-end bearing, and thrust washers — all under a single part number, sourced from the same Japanese OEM suppliers. This matters because OEM manufacturers typically sell these components separately, making ProX kits a more convenient and cost-effective rebuild solution.

ProX has also expanded its lineup to cover late-model machines equipped with plain bearing-style big-end bearings — including the Kawasaki KX250 and KX450, as well as KTM 250, 350, and 450 SX-F/EXC-F models. These plain bearing kits utilize German multi-metal technology with tin plating, engineered to handle higher engine loads and resist both bearing and pin wear more effectively than traditional needle-roller designs.

Broad Application Coverage Across Powersports

ProX connecting rod kits cover an extensive range of dirt bikes, ATVs, personal watercraft, and scooters — with applications stretching back to popular models from the 1980s. Whether you are rebuilding a two-stroke motocross machine or refreshing the bottom end of a four-stroke trail bike, ProX offers a catalogued solution engineered to OEM standards. For flat-silver cage applications in high-output motocross and sport ATV engines, ProX supplies the appropriate cage style as part of the complete kit.