PROX Crankshaft Oil Seal for BETA RR 125 2018-2019

The PROX 41.7-64661 crankshaft oil seal is designed for BETA RR 125 from 2018 to 2019. The crankshaft oil seal seals the point where the crankshaft comes out, on the ignition side or the clutch side. On a two-stroke, it keeps the crankcase airtight: a leak draws in air or gearbox oil, and the engine runs badly.

Specifications

• Brand: PROX
• Manufacturer part number: 41.7-64661
• Dimensions: 25x35x7 mm
• Engine: 2-stroke

When to replace it?

• Unstable idle, revs hanging or rising on their own.
• Gearbox oil level dropping, white smoke (clutch-side seal).
• Oil or black marks on the ignition side.

At every bottom end rebuild, and as soon as these symptoms appear.

Fitting tips

1. Drive out the old seal without scratching the housing or the crankshaft.
2. Grease the lip and press the seal in perfectly square, lip facing the inside of the engine.
3. Protect the lip as you slide it over the crankshaft thread or key.
4. Refit the cover with a new gasket.

Why PROX?

Founded in 1975 and based near Amsterdam, ProX specialises in engine and clutch wear parts for off-road bikes. The brand has most of its range made in Japan, by OEM suppliers, for quality on a par with the original parts.

Spare parts and items to plan

• Crankshaft bearings and seals : see the selection
• Complete engine gasket kit : ATHENA P400060900013 · ATHENA S410060007021

Frequently asked questions

Do the crankcases have to be split?
Not always: on some engines, the ignition-side seal can be replaced without splitting the cases. During a rebuild, replace it along with the crankshaft bearing and seal kit.

Compatibility

Check the exact model and year of your bike in the list below before ordering.

Fits:
BETA RR 125 2019
BETA RR 125 2018