Modular Expansion · 2 to 4 Bikes Two Today. Four Tomorrow. The iSi Conversion Pack turns your existing two-bike carrier into a four-bike carrier and back again in seconds. A dedicated four-bike main beam keeps both configurations at full strength, while modular components transfer between the two beams as needed. One system that scales with the ride, from solo weekenders to family holidays. Swap In Seconds Dedicated 4-Bike Beam Vehicle Caravan Compatible Lifetime Warranty How It Works Transfer. Swap. Ride. Your modular components (wheel cradles, frame supports, Tee-Handles) transfer between the two-bike and four-bike main beams. The Conversion Pack provides the dedicated four-bike beam and the additional components needed for two extra bikes. 1 Remove 2-Bike Beam Lift the two-bike main beam off the pivot base using the tool-free pivot pins. The beam separates from the mount in seconds. 2 Transfer Components Move your existing wheel cradles, frame supports and Tee-Handles across to the four-bike beam. Add the additional components from the Conversion Pack for bikes three and four. 3 Drop In 4-Bike Beam Drop the four-bike beam onto the same pivot base. Secure with pivot pins. You're now carrying four bikes on the same mount system. "Unlike racks that split a four-bike frame in half, the iSi system uses a dedicated beam for each configuration. Both the two-bike and four-bike setups remain at full structural strength." Why A Dedicated Beam Full Strength. No Compromise. Some systems try to split a four-bike rack in half to create a two-bike option. That compromises strength, adds weight, and introduces weak points at the join. The iSi approach is different. Engineered Modularity Two Beams. Zero Weak Points. Each beam is a single-piece structural member manufactured from Australian high-strength steel. There are no joints, no split points and no bolted connections in the load path. When you're running the two-bike beam, it's a complete two-bike carrier. When you're running the four-bike beam, it's a complete four-bike carrier. Both maintain the iSi lifetime warranty. Dedicated single-piece beam per configuration No split joints or bolted connections in the load path Both beams covered by the iSi lifetime warranty Rated for on-road and extreme off-road conditions What's Included In The Conversion Pack Everything you need to expand from two bikes to four. Your existing pivot base, wheel cradles and frame supports transfer from the two-bike beam. Dedicated 4-Bike Main Beam25° departure clearance with your selected carrier length Both Horizontal Wheel Support BeamsFor the four-bike configuration All Main Beam HardwarePivot pins, fasteners, everything required Additional Wheel Frame ComponentsExtra cradles and supports for bikes three and four Choose Your Length Two Lengths. One Beam Angle. Select the beam length that matches your setup. Both options use 25° departure clearance for medium ground clearance applications. 750mm CompactShorter overall length for tighter vehicle clearances 850mm ExtendedAdditional length for wider handlebar and saddle clearance One System For Every Ride Conversion Pack Key Features Swap In Seconds Transfer components between the two beams and swap the beam on the pivot base. No tools required for the beam swap itself. Vehicle Caravan Compatible with all iSi pivot base tow bar systems and caravan drawbar mount systems. The same conversion pack works on both. Full Lifetime Warranty Both the two-bike and four-bike configurations are covered by the iSi lifetime warranty. No reduced coverage for the conversion setup. 84kg Total Load The four-bike configuration supports up to 84kg total load. Up to 32kg per bike and 16kg per wheel. Rated for on-road and off-road. Lifetime Warranty 84kg Total Load (4-Bike) Made In Melbourne 30 Day Returns Not sure which length you need? Tell us your vehicle, your existing two-bike carrier model and the bikes you plan to carry. Our team will confirm the correct Conversion Pack configuration. Speak to a Sales Engineer
