My RCR 72v Won't Hold a Charge After Storage

My RCR 72v Won't Hold a Charge After Storage

This guide explains what it means when your RCR 80V only powers on while connected to the charger, and what to do next.

Common Symptoms

You may notice:

  • Bike cuts out while riding prematurely 
  • Bike powers on only when plugged into the charger
  • Display shows ~83.8V (full charge)
  • After unplugging, the bike stays on for ~15 seconds, then shuts off
  • You hear a double chirp when it powers down
  • Charger shows 83.8V, 0 amps
  • Charger fan does not engage
  • Battery does not appear to be charging

What This Means

If your bike only powers on while plugged in, this indicates:

  • The battery cannot hold operational voltage on its own
  • The charger is temporarily supplying enough voltage to power the system
  • Once unplugged, the battery cannot sustain that voltage, causing shutdown

Why This Happens

Lithium batteries require regular use and proper storage conditions to stay healthy.

A helpful way to think about it:

If you regularly feed, hydrate, and take your dog out for walks, it stays healthy and ready to play anytime you need it.

If it's left in the garage for 8 months after only given one meal, there is a good chance it won't be alive and healthy to play.

Similarly, a battery that sits unused for extended periods—especially at improper charge levels—can degrade to the point where it no longer functions properly.

At this point, the battery is likely unrecoverable.

We recommend Replacing the battery pack entirely

ONYX RCR 72v 45ah battery:
  1. Purchase Here
  2. Installation Guide
An alternative battery vendor we recommended:

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