# Unboxing & Assembling the B57A Folding eBike

> Unfolding the frame, verifying the latch, fitting the stem and pedals, and folding it back down correctly.
>
> **Applies to:** B57A folding eBike

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<sub>*Folding eBike B57A | Unboxing & Assembly* — if the player does not load, [open the video on YouTube](https://www.youtube.com/watch?v=DY3pRIc5U6w).</sub>

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## What you need

| Tool | Notes |
| --- | --- |
| 4 / 5 / 6 mm hex keys | Usually supplied |
| 15 mm spanner | Pedals |
| Torque wrench | Recommended |

**Allow 30–45 minutes.**

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## Steps

1. **Cut the carton open** and lift the bike out with a second pair of hands — folding eBikes are awkward, not heavy.
2. **Open the frame hinge.** Release the latch, swing the frame open until it stops.
3. **Verify the latch engages fully and the safety clip is closed.** This is a load-bearing joint — test it by pushing down on the frame before you ride.
4. **Raise and clamp the stem.** Fold the handlebar post up, close the clamp lever and confirm the tension is firm. If it moves under hand pressure, adjust the clamp screw.
5. **Fit the pedals.** The **left pedal is left-hand threaded** — it tightens anticlockwise. Cross-threading here is the single most common assembly mistake; see [Pedal Installation](https://help.cemotoride.com/link/343).
6. **Fit the seatpost** to roughly hip height, then fine-tune once you can sit on the bike.
7. **Check the brakes** and spin both wheels to confirm nothing rubs.
8. **Check tire pressure**, then charge and power on.

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## Folding it back down

Reverse the process: loosen the stem clamp, fold the post down, then release the frame hinge and fold the two halves together. **Route the cables so they are not trapped in the hinge.**

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## Watch out for

- **Riding with the stem clamp loose** — the most dangerous assembly error on any folding bike.
- **A frame latch that closes but does not lock** — if there is any rattle, stop and adjust before riding.
- **Cross-threading a pedal** — see [Pedal Installation](https://help.cemotoride.com/link/343).

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## Related

- [Pedal Installation](https://help.cemotoride.com/link/343)
- [Pre-Ride Inspection](https://help.cemotoride.com/link/300)
- [eBikes Overview](https://help.cemotoride.com/link/304)
- [Tutorials Index](https://help.cemotoride.com/link/393)