Crankcase seals and plugs for motorcycles
Copper O-rings are suitable for sealing oil drain plugs and can be used in combination with banjo bolts.
When using them to seal your crankcase it is important not to overtighten them. Crankcases are often made of comparatively soft aluminium, and overtightening a bolt may damage the thread. We recommend looking up the appropriate torque setting for tightening your engine's sump plug and using a torque wrench to tighten it exactly right.