ONYX RCR 45Ah Battery Fitment & Installation Guide

ONYX RCR 45Ah Battery Fitment & Installation Guide

This guide walks you through installing the ONYX 45Ah 72V battery into your RCR, including connector compatibility and frame-specific fitment steps.

Before You Begin (Important)

  • This guide applies to riders installing the ONYX 45Ah 72V battery into an RCR

  • Read the entire guide before starting

  • Always remove the battery before making any frame modifications

Connector Compatibility

Battery connector type

  • You will need the 45Ah battery uses a QS8 connector

If your bike has an Anderson connector

You will need to upgrade the battery cable before installing the 45Ah battery.

Do not attempt to force incompatible connectors together.

Frame Compatibility Overview

V1.5 Frames

  • The 45Ah battery fits similarly to a 41Ah or 23Ah battery

  • No cutting or bending required

Installation tip:
Insert the battery at a slight angle, with the seat side down first, for a clean fit.

V1 Frames

  • Minor modification is required to allow proper clearance

  • Follow the steps below carefully

Modifying a V1 Frame (Required)

Step-by-step instructions

Step 1: Remove panels and battery

  1. Remove the side panels.

  2. Remove any battery currently installed.


Step 2: Prepare the battery tray

  1. With the battery fully removed from the bike, locate the right and left sides of the battery tray.

  2. Cut small slits in both sides of the tray, as shown in the reference photos.

  3. Perform all cutting and bending with no battery in the tray.

This modification must be done on both sides of the bike.

Step 3: Create clearance

  1. Using a mallet or pliers, gently bend the cut sections outward.

  2. Only bend enough to create the needed clearance—do not over-bend.

Step 4: Insert the battery

  1. Insert the 45Ah battery using a seat-side-down angle first.

  2. Carefully lower the battery into place once aligned.

Step 5: Secure the battery

  • Secure the battery using straps

  • Battery straps are recommended for all RCR models, regardless of frame version

Step 6: Reinstall components

  1. Reinstall the seat.

  2. Reinstall all side panels.

  3. Confirm the battery is fully seated and secure.

Final Checks

Before riding:

  • Confirm the QS8 connector is fully seated

  • Ensure the battery is secure and not shifting

  • Verify no wiring is pinched during installation

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