Rennen Infinity Chainring Bolts Titanium 5pcs

Overview

The Rennen Infinity Chainring Bolts are precision-engineered titanium fasteners designed to secure chainrings to BMX cranks with superior strength and load distribution. Manufactured in-house from USA-made 6AL-4V titanium, these bolts feature a load-distributing shoulder and reinforced 4mm internal hex for maximum durability and reliability.

Key Features

• Load-Distributing Shoulder — Integrated shoulder just below bolt head disperses clamping pressure across a wider area; reduces concentrated stress on chainring and crank spider, significantly improving bolt and component longevity
• 6AL-4V Titanium Construction — Aerospace-grade titanium alloy provides exceptional strength-to-weight ratio and corrosion resistance; superior durability compared to steel alternatives
• 4mm Internal Hex — Smaller hex size (versus standard 5mm) increases bolt material thickness by 8.5%; delivers enhanced strength and reduced risk of head stripping
• Optimized Regular Length — 6.2mm length engineered to work reliably with most standard gear and crank combinations; eliminates guesswork in bolt selection
• In-House CNC Manufacturing — Produced on state-of-the-art multiaxis CNC lathe with full design control; ensures consistent quality and precision across every bolt
• FEA Engineered Design — Refined through 97 CAD iterations, 22 CNC programming variations, and finite element analysis simulations; represents optimized stress distribution and load handling
• Lifetime Warranty Against Breakage — Rennen guarantees replacement for any bolt that breaks during use; reflects confidence in design and manufacturing quality
• Included Anti-Seize Packet — 1oz of Finishline Ti-Prep anti-seize compound prevents galling and simplifies future removal

Technical Specifications

• Material: USA-made 6AL-4V titanium alloy
• Bolt length: 6.2mm (Regular)
• Nut length: 6.2mm (Regular)
• Internal hex size: 4mm (assembly tool: 4mm/8mm allen wrenches)
• Quantity: 5 bolts per set
• Finish: Polished titanium
• Included: 1oz Finishline Ti-Prep anti-seize compound
• Warranty: Lifetime against breakage

Compatibility & Ideal Use Cases

Compatible with all BMX cranksets using standard chainring bolt holes. Regular length (6.2mm) fits most standard crank and gear combinations. XL length available for thick crank spiders like Answer Accelerator cranks; XXL available for RaceFace SixC Carbon cranks. The load-distributing shoulder and reinforced design make these bolts ideal for riders seeking maximum chainring security and crank longevity. Essential for high-stress trick riding, racing, and demanding conditions where chainring security is critical. The lifetime warranty and superior engineering justify premium pricing for riders prioritizing reliability and long-term component protection.

While all other bolts on the market use a 5mm internal hex we chose 4mm to provide more material and increasing their strength further by 8.5%

At Rennen we like improving things that are not obvious and we believe we have achieved that with the Infinity Chainring Bolt.

Rennen are so confident in this design we are offering a lifetime warranty against breakage. That's right break a bolt and get a new one.

For something as simple as a chainring bolt we ran this design through 97 CAD iterations, 22 CNC G-Code variations and numerous FEA simulations.

We purchase USA made 6AL-4V Titanium and produce these on a state of the art multiaxis CNC lathe in house. We do things this way because we have full control over our designs and production, and the alternative of ordering parts out of a catalog is unoriginal and boring.

Rennen stands by their designs and products, the quality shows.

Chainring Bolts use a 4mm/8mm allen wrenches for assembly.

Regular length has been optimized to work with most gear crank combinations.

XL is specifically designed for thick crank spiders like Answer Accelerator cranks. XXL is made for RaceFace SixC Carbon cranks.

Titanium Bolts come with 1oz of Finishline Ti-Prep anti seize packet.

We use Finite Element Analysis (FEA) to virtually test the design and rapidly iterate through concepts.
In this first Image we are showing in an exaggerated view what happens when a load is applied to the spider and transmitted through the gear. This is a design with no shoulder. Here you can see concentrated stress.

Our second image is demonstrating the effects of the shoulder. Notice how there is more distribution of stress and the regions of high stress are not as pronounced.
We look to improve designs that have been in existence for decades.
We have improved the Chainring bolt and we at Rennen hope you appreciate the effort.