Honda Monkey125: problems, complaints, bulletins

Summary for the Honda Monkey125 across 1 model years: 2 owner complaints and 0 NHTSA service bulletins, plus repair videos. Pick a year for details.

Model years

Year	Owner complaints	involving a crash	Technical service bulletins (TSB)	YouTube repair videos
2023	2	0	0	0

What fails most often

1 Engine 50% of all complaints
2 Powertrain 50% of all complaints

Circle size and colour show each component’s share of NHTSA complaints. Schematic only, not a drawing of the exact model.

Engine: 1 complaints (50% of all).
Powertrain: 1 complaints (50% of all).

Symptoms owners describe

How many of the 2 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).

warning lights, check engine1 · 50%
knocking, grinding or other noise1 · 50%

Components owners complain about

Component	Owner complaints	involving a crash	Technical service bulletins (TSB)
Engine	1	0	0
Powertrain	1	0	0

What owners report

Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.

The contact stated while riding at approximately 45 MPH, the contact heard a grinding sound coming from the engine. The contact rode the motorcycle back to the residence. The contact stated no warning light was illuminated. The contact had not taken the motorcycle to a local dealer or independent mechanic.
Engine · 2023 · 2024-09-03 · NHTSA complaint #11612204
The 5 speed transmissions have a very well known defect among the community of owners. A general post from the thousands that have this same issue. I finally took my 22 in to the dealership to fix the transmission noise (warranty expires next month).
Powertrain · 2023 · 2024-07-31 · NHTSA complaint #11605707

What to check before buying

Engine. Cold start, unusual noises, oil leaks and engine codes.
Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.

Other models of this make

Read also

Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-06.