Countershaft Seal Kit - Honda CR125 86-03 25-4010

The All Balls Racing 25-4010 Countershaft Seal Kit is a complete repair kit for the front sprocket area of the Honda CR125R, 1986-2003. Rather than supplying a seal on its own, the kit pairs a case-hardened bushing with an upgraded outer seal plus the small parts needed to finish the job, so a weeping countershaft can be fixed properly in one go.

It suits riders and workshops chasing the cause of a persistent gearbox oil leak behind the front sprocket, where a worn or scored countershaft surface will chew out a new seal in short order. The hardened, coated bushing restores a clean sealing surface and resists corrosion, while the seal compound is chosen to be kinder to the bushing over the long term.

Please confirm fitment against your model and year before ordering.

• Complete countershaft seal repair kit for Honda CR125R 1986-2003
• Case-hardened bushing restores a clean sealing surface and reduces seal damage
• Coated bushing for improved corrosion resistance
• Upgraded seal material reduces bushing wear for longer service life
• Supplied with the O-rings, snap rings or lock washers required to complete the repair
• All Balls Racing part number 25-4010

• Case-hardened countershaft bushing
• Replacement outer countershaft seal
• O-rings, snap rings or lock washers as required for the application

Confirm fitment against your machine's model and year before ordering or opening the kit.
Drain or lower the transmission oil before removing the front sprocket and old seal so oil does not run out during the repair.
Remove the old seal carefully and avoid scoring the countershaft or the seal housing bore in the case.
Clean the countershaft, sprocket splines and housing thoroughly and remove all old sealant, debris and metal particles before assembly.
Lightly lubricate the seal lip and the bushing with clean engine oil before fitting to avoid dry-running damage on start-up.
Drive the new seal in square to its housing using a suitable seal driver or socket; do not tap on the seal lip.
Fit any supplied O-rings, snap rings or lock washers in the same positions as the parts you removed, and make sure snap rings are fully seated in their grooves.
Refill the transmission with the oil grade and quantity specified in the Honda service manual, then check for leaks after the engine reaches operating temperature and again after the first ride.
Keep chain tension and alignment within specification, as a tight or misaligned chain loads the countershaft and shortens seal life.
Store unused kits in their sealed packaging in a cool, dry place away from direct sunlight, fuels and solvents to protect the rubber components.