
Overview
The CHIHAI MOTOR 370 brushed DC motor range offers gold high-speed and black torque-oriented configurations, with motor-only, bevel-gear, MP9 spur-gear and plug-in lead choices. Select the exact configuration: speeds, winding, gear and connection hardware vary by option.
Features
- Compact permanent-magnet brushed DC construction with ball bearings and balanced armature.
- Gold and black winding alternatives for different speed and torque requirements.
- Gear-equipped and locking plug-in lead versions available as listed.
- Original motor geometry and configuration-specific shaft details retained for mechanical comparison.
Specifications
| Brand | CHIHAI MOTOR |
|---|---|
| Motor family | 370 brushed DC; gold CHR-K370WD and black / MP9 configurations |
| Magnet and bearing construction | NdFeB permanent magnets; ball bearings; dynamically balanced armature |
| Gold reference body | 24.4 mm diameter × approximately 31 mm length (drawing: 30.8 mm) |
| Gold reference shaft | 2.0 mm diameter; 1.5 mm D-flat dimension; projection 9.5 ± 0.3 mm |
| Gold reference mounting | 2 × M3 mounting holes; 17.0 mm spacing; drawing also marks 15° and 18.5 mm rear spacing |
| Gold reference length | 41.7 mm overall; 6.45 mm front boss diameter; 1.7 mm boss projection |
| Gold reference mass | Approximately 52 g; other configurations and accessories differ |
| Reference supply | 11.1V DC; selected MP9 and wired gold references also list 7.4V operation |
| Gold selector speed | 50,000 rpm class; wired gold artwork lists 52,000 rpm at 11.1V and 34,000 rpm at 7.4V |
| MP9 Gold speed | 50,000 rpm at 11.1V; 33,000 rpm at 7.4V |
| MP9 Black medium-torque speed | 33,000 rpm at 11.1V; 22,000 rpm at 7.4V |
| MP9 Black high-torque speed | 28,000 rpm at 11.1V; 18,000 rpm at 7.4V |
| Black bevel-gear option | 26,000 rpm in selector; wired black bevel option lists 28,000 rpm. Keep configurations distinct. |
| Plug-in lead versions | 15 cm custom locking terminal leads; do not pull the latched contacts out forcibly |
| Bevel-gear reference | 9-tooth D-bore metal injection-molded gear where pictured; not interchangeable with MP9 spur-gear versions |
| MP9 construction | Gold: N35SH sintered NdFeB; medium-torque black: bonded NdFeB; high-torque black: N35SH high-performance NdFeB. Ball bearings, metal brush assembly and balanced armature; check selected shaft/gear fit. |
Gold CHR-K370WD Performance Reference
The following 11.1V test points apply to the gold CHR-K370WD reference, not every black or MP9 winding. The 61,000 rpm no-load test point differs from the 50,000 rpm option designation and 52,000 rpm product reference. Use the selected winding and its operating point for matching; these figures do not establish a continuous-duty rating.
| Test voltage | 11.1V DC |
|---|---|
| No-load speed / current | 61,000 rpm / 2.9 A |
| Maximum-efficiency point | 147 W; 52,800 rpm; 270 g·cm torque; 18.7 A |
| Maximum-power point | 317 W; 32,000 rpm; 1,010 g·cm torque; 58.55 A |
| Stall torque / current | 2,020 g·cm / 120 A; do not operate stalled |
Configuration Guide
Gold 50000 rpm - Motor Only; Titanium Black 28000 rpm - Motor Only; Gold 50000 rpm + Bevel Gear; Black 26000 rpm + Bevel Gear; Black 28000 rpm + Plug-in Leads; Gold + Plug-in Leads; Black 28000 rpm + Bevel Gear + Leads; Gold + Bevel Gear + Leads; MP9 Gold 50000 rpm + Spur Gear + Leads; MP9 Black 33000 rpm + Spur Gear + Leads; MP9 Black 28000 rpm + Spur Gear + Leads; MP9 Gold 50000 rpm - No Gear; MP9 Black 33000 rpm - No Gear; MP9 Black 28000 rpm - No Gear.
MP9 spur-gear and standard bevel-gear configurations are different mechanical arrangements. The standard bevel-gear configuration is not an MP9 spur-gear substitute. Check shaft, gear mesh, clearance and electrical requirements before fitting. Gold options without an explicit selector speed are shown with a 52,000 rpm reference in their configuration artwork.
Applications
For compatible compact hobby mechanisms requiring a 370-format brushed DC motor. Match the selected winding, shaft, gearing and supply to the mechanism; motor size alone does not establish fit or operating suitability.
What's Included
One selected motor. A bevel gear, MP9 spur gear and/or lead pair is included only when named in the selected configuration. Motor-only and no-gear versions do not include a gear. Comparison images show alternatives, not a multi-motor package. Power supply, controller and complete mechanism are not included.
Installation and Operation
- Use a DC supply matched to the selected winding. Do not treat a general motor-family voltage range as this motor's rating.
- Avoid overload and stall; speed decreases as load rises. Stall figures are transient reference values, not an operating condition.
- High-speed gold and MP9 versions can run hot; assess current demand and cooling for the actual duty cycle.
- Locking plug-in terminal leads resist withdrawal. Do not force them out; perform any required soldering on the free wire ends and avoid overheating the motor terminals.
- Check torque requirements before reducing speed; audible motor noise varies with speed and load.
FAQ
Does every option include a gear and wires?
No. Only configurations explicitly naming a gear or leads include those items.
Do all versions run at 50,000 rpm?
No. Black, gold and MP9 windings have different speed references; select the listed configuration and supply voltage.
Can I use the stall current as a normal operating current?
No. Avoid stalled operation and overload. The stall figures are reference limits, not continuous-duty ratings.
Can I swap the bevel and MP9 spur gears directly?
They are different configurations. Check the required shaft, gear mesh and mechanical fit before selecting.
Visual Details






