Renthal Twinring Rear Sprocket
MSRP: $119.95
$95.96
Exact Fitment Guarantee
The Renthal Twinring Rear Sprocket is a revolutionary hybrid rear sprocket engineered to solve the age-old motocross dilemma: the featherweight agility of aluminum versus the multi-season longevity of heavy steel. Standard 7075 aluminum sprockets wear out quickly in mud and sand, while solid steel sprockets add significant unsprung, rotating weight that slows down suspension response and throttle acceleration. The Renthal Twinring combines the best of both worlds through a patented bi-metal construction.
The outer tooth ring is manufactured from case-hardened, high-strength nickel-coated steel, providing extreme wear resistance that outlasts standard aluminum sprockets by up to three times in brutal abrasive conditions. The inner carrier is CNC-machined from ultralight aerospace-grade 7075-T6 aluminum, keeping rotating unsprung mass to an absolute minimum. The steel outer ring is heat-expanded and shrunk onto the aluminum inner carrier, then locked permanently into place with high-tensile flat-head rivets. Mud-clearing grooves are precision-machined into the tooth roots to prevent chain packing in deep mud.
- Outer Ring: Case-hardened nickel-coated carbon steel tooth ring
- Inner Carrier: CNC-machined 7075-T6 aerospace-grade aluminum core
- Assembly Method: Thermal shrink-fit joined with high-tensile mechanical rivets
- Mud Evacuation: Machined self-cleaning mud grooves at tooth roots
- Wear Longevity: Up to 300% longer operational life compared to 7075 aluminum
### Step-by-Step Installation & Safety Protocols Installation requires a set of new tapered sprocket bolts and locking nuts (never reuse old sprocket hardware). Clean the rear wheel hub mounting surface of all dirt and burrs. Position the Renthal Twinring against the hub flange, align the mounting holes, and insert new high-tensile sprocket bolts coated with medium-strength thread locker. Tighten the nuts in an alternating criss-cross star pattern, torquing evenly to factory specification (typically 32 to 36 Nm). Ensure the sprocket spins true with zero lateral wobble before installing the wheel into the swingarm.
### Maintenance & Service Inspection Maintenance is remarkably low: inspect tooth profiles during regular bike washes. The case-hardened steel teeth will retain their symmetrical profile for dozens of hard riding hours before displaying slight tooth hook wear.
Frequently Asked Questions
Q: How much longer does a Twinring sprocket last compared to an all-aluminum sprocket?
A: Due to the case-hardened steel outer tooth ring, the Renthal Twinring typically lasts up to three times longer than standard 7075 aluminum sprockets, making it the premier choice for sand, mud, and cross-country racing.
Q: Is the Renthal Twinring significantly heavier than an aluminum sprocket?
A: While slightly heavier than a 100% aluminum sprocket, the Twinring is substantially lighter than a traditional solid steel sprocket because the large central carrier is CNC-machined from lightweight 7075-T6 aluminum.
Q: Should I use new sprocket bolts when installing the Twinring?
A: Yes. Always install new high-grade sprocket bolts with locking nuts and thread locker, as reusing old stretched bolts can lead to loose hardware that damages your rear wheel hub.
Q: What pitch chain is compatible with the Renthal Twinring?
A: The Twinring is precision-machined for standard 520 pitch motocross and off-road drive chains.