
Product: ROKR Parallel World Marble Run The Last City & The Future City
SKUs: MR01S (The Last City) and MR02S (The Future City)
Product type: Plastic marble run
Quick answer: This guide covers the official parts references and the most common lift-module and ball-jamming checks for ROKR Parallel World MR01S and MR02S. For the full build sequence, use the Assembly Guide. If a part is missing, broken, uncut, or visibly warped, request it through Part Replacement.
In This Guide
Before You Troubleshoot
- Confirm whether you are working on The Last City (MR01S), The Future City (MR02S), or the shared lift module.
- Use the correct instructions: The Last City assembly manual or The Future City assembly manual.
- Remove the steel balls and disconnect the Type-C power connection before disassembling or repositioning lift-module parts.
- Compare the part labels and orientation carefully before pressing parts back into place.
Parts Reference
What Size Steel Ball Does MR01S or MR02S Use?
Use the supplied 8 mm steel balls. Steel balls from other ROKR marble-run products may not be the same size and should not be substituted unless their diameter is confirmed.
Which Lift-Module References Should I Use for Replacement Parts?
The lift-module motor and circuit-board references are MRL01-P1 and MRL01-P2. Check these labels carefully when completing a replacement-parts request so the correct component is selected.
Lift and Ball-Jamming Problems
Why Is the Lift Module Stuck?
Possible causes: The steel ball needs cleaning, gears F1 and F2 are not aligned with P3 and P4, or P3 and P4 were installed in the opposite direction.
Solution: Wipe the steel ball before testing again. If the lift still does not move freely, disassemble the affected gear section and align F1 and F2 with P3 and P4. Make sure F1 and F2 are seated correctly before removing P7, then confirm that P3 and P4 face the direction shown in the manual.
Why Is a Ball Stuck in the Upper Part of the Lift Module?
Check: Part E3 may be reversed front-to-back, or its opening may face the wrong direction.
Solution: Remove E3 carefully and reinstall it with the correct face and opening direction. Compare both views below before reassembling the surrounding parts.
Why Is a Ball Stuck in the Lower Part of the Lift Module?
Cause: Part P11 may be missing.
Solution: Check the lower lift-module position shown below and install P11 before operating the lift again. If P11 is missing from the kit or is damaged, use the replacement service linked in the Quick Answer.
Need More Help?
If your issue is not covered here or the problem continues after these checks, email service@robotime.com or contact Robotime Support.
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