RK Racing Chain 520-SO-110 520 Series O-Ring Chain - Durable Street

In this review the RK Racing Chain 520-SO-110 is presented as a solid, budget-conscious option for riders needing a reliable sealed chain. It is aimed at owners of low to mid-range motorcycles or ATVs up to 400cc who want a traditional round O-ring chain that keeps lubrication sealed and delivers consistent power with minimal drag. The single biggest reason to buy is the balance of durability and value: the SO O-ring compound and 6,900 lb tensile strength deliver dependable service without the premium price of race-oriented chains.

Key Features

• O-ring construction: The SO O-ring made from Nitrile Butadiene seals lubrication effectively to reduce wear and extend service life.
• Versatile 520 size: The 520 series fits many low to mid-range motorcycles and can be used for both street and off-road up to 400cc.
• Solid tensile strength: A 6,900 lb tensile rating provides a reassuring margin for engines up to the listed 60 HP limit.
• Included master link: The clip-type connecting link simplifies installation and makes chain replacement straightforward for home mechanics.
• Lightweight per length: At about 3.39 lbs per 100 links the chain keeps rotating mass reasonable for everyday riding.

Who It's For

The 520-SO-110 is best for riders of commuter bikes, small sport bikes, dual-sport machines, and ATVs in the up to 400cc class who want a sealed O-ring chain that is easy to source and service. It is a practical pick when durability and routine maintenance intervals are important but extreme performance is not the priority.

Riders with high-performance machines above 60 HP, racers, or anyone requiring the lightest, most advanced link coatings or clipless master links should look elsewhere for premium race-spec chains. Also, those who expect zero fitment work should note that fit and master link experience can vary; having basic tools and a shop manual helps.

Pros & Cons

Pros

• Good long-term durability and lubrication retention thanks to the Nitrile Butadiene O-ring.
• Clear value for money compared with higher-end sealed chains, offering solid performance for everyday use.
• Appropriate tensile rating and a usable max horsepower and CC envelope for many street and off-road bikes.
• Master link included makes replacement achievable for competent home mechanics.

Cons

• Fit and installation experience is mixed among customers, so some riders may need to make minor adjustments or seek help with the master link.
• Not intended for high-horsepower or race applications beyond the 60 HP rating.

Specifications

Series	520-SO (520 Series)
O-ring Type	SO Nitrile Butadiene
Tensile Strength	6,900 lbs
Max CC / Use	400cc Street, 400cc Off-road/ATV
Max Horsepower	60 HP
Weight per 100 Links	3.39 lbs
Master Link	Clip type included

Our Verdict

The RK Racing Chain 520-SO-110 is a dependable, affordable sealed chain for riders of low to mid-range bikes and ATVs up to 400cc. It combines proven SO O-ring lubrication retention with a robust tensile rating, making it a sensible choice for everyday street and off-road use where long life and straightforward maintenance matter more than race-level performance.

Frequently Asked Questions

Can this chain be used off-road?
Yes, the 520-SO is rated for off-road use up to 400cc and is designed to retain lubrication in harsher conditions.

Is the master link included suitable for home installation?
The clip-type master link is included and allows home installation, though some users report mixed ease-of-fit so basic tools and care are recommended.

Will this chain fit my bike?
The chain is 520 series and fits bikes specified for that size; verify your OEM chain size and sprocket fitment before purchase.