Ronstan RF46101 Series 40 Single Auto 40mm Ratchet Orbit Block Pulley with Dyneema Link Head

Technical data

Colours and design may vary from those shown.

Package

• 1 x Ronstan RF46101 Series 40 Single Auto 40mm Ratchet Orbit Block Pulley with Dyneema Link Head

Sold individually. The price is for one pulley; order two if you want a pair. This product does not include speed system lines. We recommend a suitable 5mm diameter cord around 150cm long, such as the Charly Powerlock Speed System Cords.

Optional extras

• Suitable speed system lines (we recommend 5mm diameter cord around 150cm long)

Ronstan Orbit Block Auto Ratchet Pulley 40mm RF46101

The Ronstan RF46101 is a top-of-the-range 40mm diameter Orbit Block ratchet pulley (also known as a "winch pulley") featuring ball bearings and an intelligent automatic load-sensing mechanism.

When the paraglider speed system is applied, the ratchet mechanism automatically engages, locking the pulley wheel in place. This greatly decreases the effort required to hold the speed bar with your legs, significantly reducing fatigue and allowing you to push the speed system for much longer periods. When you release the speed bar, the ratchet disengages and unlocks the wheel so the speed system line runs out smoothly and freely—perfect for rapid, safe easing of the speed bar.

Like most premium pulleys, the Ronstan RF46101 is primarily designed and manufactured for highly demanding marine and sailing applications (such as dinghy mainsheet systems and sports boats). However, its exceptional holding power and automatic mechanics also make it ideal for high-end paragliding. Because these pulleys are engineered for sailing rather than a specific paragliding harness, they are not universally "plug-and-play." Buyers must adapt these high-performance pulleys to best suit their individual harness setup, which usually involves professional modification to ensure they are fitted safely, securely, and effectively.

Features

• Up to 14:1 holding power – the highest available, almost double that of its nearest competitor.
• Fully automatic load-sensing ratchet engagement.
• Smooth easing of lines when untensioned.
• Easily fitted and securely retained Dyneema link head.
• Sophisticated NC-machined sheave featuring 8 straight gripping faces to distribute load, resist movement, and minimize line wear.
  
• Premium Materials: Anodised Aluminium sheave, high-compression carbon black Acetal ball bearings, toughened glass-fibre reinforced Nylon frame, and a UV-stabilised SK75 Dyneema link.
  

Awesome ratchet block holding power

Quite simply, Ronstan Ratchet Orbit blocks™ have the highest holding power available. The sophisticated NC-machined sheave features Generation 2 of our patented sheave cross-hole geometry. The Series 40 delivers up to 14:1 holding power, almost double that of our nearest competitor.

The unique sheave design has 8 gripping faces which directly resist loaded line movement. Traditional designs have an angled resistance to line movement. Our Generation 2 design has straight resistance faces which both distribute the load and minimise rope wear. These faces are offset from the radial line, to draw the rope down into the gripping area when under load.

Materials

• Sheave: Anodised Aluminium
• Ball Bearings: High compression strength carbon black Acetal
• Frame/Cheeks: Toughened, glass fibre reinforced Nylon
• Rope Link: UV stabilised, multi-strand impregnated SK75 Dyneema®

Applications

• Paraglider harness speed systems
• Dinghy mainsheet systems
• Mainsheet fine tune systems on sports boats & small keel boats
• Mainsheet systems on sports boats using RF7 mainsheet swivel cleat unit
• Spinnaker and job sheets on dinghies - especially modern asymmetric classes
• Control line applications on larger yachts

Downloads

• Ronstan downloads section

Manuals

User Instructions

• BB & RT Orbit Block™ User Instructions

RF46101 Series 40 RTA Orbit Block, Auto, Single, Link Head

Series 40 RTA Orbit Block, Auto, Single, Link Head

Use, Compatibility, and Fitting

Suitability

The Ronstan RF46101 Series 40 Auto Ratchet Pulleys are highly specialised, premium upgrades. They are primarily used on performance-oriented paragliding harnesses, especially high-end cross-country (XC) and competition setups.

Fitting Requirements (Important)

These pulleys are not universally "plug and play." Installation generally falls into one of two categories:

Direct Replacement (The Exception): A few high-end harnesses—such as the Advance IMPRESS 4—are specifically designed so you can remove the standard speed system pulleys and directly replace them with these 40mm Ronstan ratchet blocks without any harness modifications.

Professional Modification (The Rule): Unless your harness's product info or user manual explicitly states that it accommodates 40mm ratchet blocks directly, you must assume it will require modification by a qualified paraglider harness service centre.

When modification is required, a professional service centre will typically need to safely adapt the harness by:

Adding Webbing Loops: Securely sewing in extra structural webbing loops specifically positioned to accommodate the larger 40mm pulleys.

Attaching the Pulleys: Connecting the pulleys to these new webbing loops using a suitable, high-strength maillon or specialized soft link (or occasionally stitching the attachment points directly).

How to Check Compatibility for Your Harness

To determine if these can be fitted to your specific equipment, you must:

1. Read the user manual and product information for your paragliding harness to check for explicit 40mm block compatibility.
2. Review the Ronstan RF46101 product specifications.
3. Verify that your harness has sufficient physical space to accommodate a 40mm block without obstructing other lines or speed systems.

Please ensure you have a plan for professional installation before purchasing if your harness does not already feature dedicated, appropriately sized attachment points.