The Track Roller, also known as Bottom Roller or Lower Roller, is an important undercarriage component installed beneath the track frame of Kubota KX121 crawler excavators.
The roller carries the machine operating weight, supports the track chain and maintains proper crawler alignment during travelling and excavation operations.
For compact excavators like Kubota KX121, track rollers are exposed to:
A worn or damaged track roller may cause:
Our Kubota KX121 track rollers are manufactured using professional undercarriage production technology to provide reliable aftermarket replacement solutions for equipment dealers, repair workshops and machine owners.
Designed for:
Reference OEM numbers:
Different production years may use different OEM references. Please confirm before purchase.
Manufactured from:
40Mn2 Alloy Steel
Advantages:
The roller tread surface is induction hardened.
Specification:
Provides improved resistance against:
Equipped with:
Designed to prevent:
Manufactured with:
Provides direct bolt-on replacement without modification when the correct model is selected.
| Item | Specification / Detail |
|---|---|
| Product Type | Excavator Undercarriage Track Roller |
| Machine Model | Kubota KX121 Series |
| Compatible Models | KX121 / KX121-2 / KX121-3 |
| Machine Class | Approx. 5-6 Ton Excavator |
| OEM Part Number | RD101-99900 / RD118-21700 / RD148-21700 |
| Material Grade | 40Mn2 Alloy Steel |
| Manufacturing Process | Forging / Casting + CNC Machining |
| Heat Treatment | Induction Hardening |
| Surface Hardness | HRC 52-58 |
| Hardening Depth | 5mm-10mm |
| Seal System | Heavy-duty Floating Oil Seal |
| Lubrication System | Lifetime Internal Lubrication |
| Bearing Structure | Hardened Shaft + Wear-resistant Bushing |
| Quality Inspection | Dimension, Hardness and Sealing Inspection |
| Flange Type | Single Flange / Double Flange |
| Installation | OEM-Style, Bolt-on Direct Replacement |
| Application | Construction / Landscaping / Earthmoving |
| Shipping Note | Small Component — Air or Sea Freight Available |
The Track Roller, also known as Bottom Roller or Lower Roller, is an important undercarriage component installed beneath the track frame of Kubota KX121 crawler excavators.
The roller carries the machine operating weight, supports the track chain and maintains proper crawler alignment during travelling and excavation operations.
For compact excavators like Kubota KX121, track rollers are exposed to:
A worn or damaged track roller may cause:
Our Kubota KX121 track rollers are manufactured using professional undercarriage production technology to provide reliable aftermarket replacement solutions for equipment dealers, repair workshops and machine owners.
Designed for:
Reference OEM numbers:
Different production years may use different OEM references. Please confirm before purchase.
Manufactured from:
40Mn2 Alloy Steel
Advantages:
The roller tread surface is induction hardened.
Specification:
Provides improved resistance against:
Equipped with:
Designed to prevent:
Manufactured with:
Provides direct bolt-on replacement without modification when the correct model is selected.
| Item | Specification / Detail |
|---|---|
| Product Type | Excavator Undercarriage Track Roller |
| Machine Model | Kubota KX121 Series |
| Compatible Models | KX121 / KX121-2 / KX121-3 |
| Machine Class | Approx. 5-6 Ton Excavator |
| OEM Part Number | RD101-99900 / RD118-21700 / RD148-21700 |
| Material Grade | 40Mn2 Alloy Steel |
| Manufacturing Process | Forging / Casting + CNC Machining |
| Heat Treatment | Induction Hardening |
| Surface Hardness | HRC 52-58 |
| Hardening Depth | 5mm-10mm |
| Seal System | Heavy-duty Floating Oil Seal |
| Lubrication System | Lifetime Internal Lubrication |
| Bearing Structure | Hardened Shaft + Wear-resistant Bushing |
| Quality Inspection | Dimension, Hardness and Sealing Inspection |
| Flange Type | Single Flange / Double Flange |
| Installation | OEM-Style, Bolt-on Direct Replacement |
| Application | Construction / Landscaping / Earthmoving |
| Shipping Note | Small Component — Air or Sea Freight Available |
