Selecting the right timing chain is critical for dirt bike engines. The chain size and pitch match specific engine families, helping maintain accurate valve timing under load, reduce wear, and extend service life. This guide highlights five timing chains commonly used on 50cc to 250cc dirt bikes, ATVs, and go-karts. Each option is evaluated for fitment, durability, and installation considerations to help riders choose a dependable upgrade or replacement. The table below summarizes the five options discussed here. Always verify compatibility with your model before purchase.
| Product | Brand | Size / Pitch | Notes |
|---|---|---|---|
| TC-Motor 84-Links Cam Timing Chain | TC-Motor | 84 Links, 25H | For 110cc ATVs and dirt bikes; Honda TRX90/X compatibility |
| 84 Link Engine Starter Cam Timing Chain | Kids ATV Parts Inc | 84 Links, 25H | Fits 50cc–125cc Chinese ATVs and go-karts |
| 25H 62 Timing Chain Link | YD-PS001 | 62 Links, 25H | Fits 50cc–125cc Chinese ATVs and dirt bikes |
| TC-Motor 90 Links Timing Chain | TC-Motor | 90 Links, 25H | For YX Piranha GPX 140cc and similar engines |
| TC-Motor NC250 Timing Chain | TC-Motor | 7x100L | For Zongshen ZS177MM 250cc engines |
Introduction to the selections: The five products above cover a range of common displacement classes and engine families found in American-accessible dirt bikes and ATVs. They share the core goal of restoring proper timing, minimizing chain stretch, and preserving engine timing accuracy. When choosing among them, riders should verify the exact link count and pitch required by their engine, confirm the chain type (timing vs. drive), and assess compatibility with any tensioners or guides already installed on the machine. The following product sections provide concise details to help with quick comparisons.
TC-Motor 84-Links Cam Timing Chain For 110cc Dirt Bikes
The TC-Motor chain uses 84 links in a 25H pitch, designed for 110cc class engines frequently found in ATVs and dirt bikes. It targets common platforms such as Honda TRX90/TRX90X (model years 1993–2018), making it a practical replacement for worn timing chains in many popular small-displacement machines. The listing emphasizes careful fitment, advising customers to review the description to ensure the correct part is purchased. A safety package is included to protect the product during shipping, helping preserve chain integrity on arrival.
Key features and considerations include the 84-link length and 25H pitch, which align with compatible 110cc engines. Proper installation typically involves aligning timing marks, checking chain tension after installation, and confirming smooth operation without binding. This chain is positioned as a straightforward upgrade for riders seeking reliable timing with minimal modification, and it benefits from being paired with appropriate guides and tensioners if your model requires them.
- 84 links, 25H pitch
- Suitable for 110cc ATVs and dirt bikes
- Safety packaging included
84 Link Engine Starter Cam Timing Chain For 50cc–125cc ATVs
This 84-link engine starter timing chain is designed for a broad range of 50cc to 125cc Chinese ATVs, dirt bikes, and go-karts. Its 84-link configuration and 25H pitch ensure compatibility with many common sub-125cc platforms from brands like Taotao, SunL, Peace, JCL, and Baja. The listing notes that the chain is brand-new and intended as a reliable replacement when OEM components wear. As with other timing chains, correct installation and tensioning are essential to preserve accurate timing and engine performance.
Practical considerations include verifying engine compatibility, ensuring the chain length matches the engine’s timing requirements, and using appropriate tensioners and guides if applicable. Buyers should also check the packaging and documentation for any model-specific notes. This chain represents a cost-effective option for owners seeking a durable, high-link replacement to restore timing reliability on smaller-displacement machines.
- 84 links, 25H pitch
- Fits 50cc–125cc Chinese ATVs and dirt bikes
- Brand-new condition
25H 62 Timing Chain Link For 50–125cc ATVs
The 25H 62 timing chain features a 62-link configuration with a 25H pitch, designed for a wide span of 50cc to 125cc Chinese ATVs and dirt bikes. This size is common on many entry-level and mid-range machines, making it a practical replacement option where length and pitch align with the engine specifications. The product description notes that it is a new chain suitable for use with various Chinese-made brands, which often share similar timing-chain architectures. Installation success hinges on matching the chain to the engine’s exact spec and ensuring compatible guides and tensioners are used.
When evaluating this chain, consider the engine family and displacement, the exact timing requirements, and whether your model uses a 62-link timing chain with 25H pitch. The 62-link length can be ideal for certain OEM replacement schedules and may provide a stable balance of durability and wear resistance for daily riding and light competition.
- 62 links, 25H pitch
- Fits 50cc–125cc Chinese ATVs and dirt bikes
- New condition; generic compatibility
TC-Motor 90-Links Timing Chain For 140cc Dirt Bikes
This TC-Motor timing chain features 90 links, designed for 140cc engines used in dirt bikes and pit bikes, including compatibility with Honda CRF110 engines and other similar 140cc platforms. The listing indicates compatibility with a range of engines such as Jialing 124cc, GPX 140cc, Piranha 140cc, and ZS250 variants, reflecting a broad applicability within this displacement category. The product includes a safety package to protect the item during transit and reminds buyers to confirm correct fitment by reviewing the description carefully before purchase. Proper sizing and tensioning remain critical for reliable operation.
Key considerations include matching the chain length to the engine’s timing requirements and ensuring the chain aligns with existing guides and tensioners. With a longer 90-link chain, ensure the compatibility with your sprockets and the space available around the crankcase. Regular inspection for wear and proper lubrication helps maintain timing accuracy and engine health in mid-range displacements like 140cc.
- 90 links, 25H pitch
- Suitable for 140cc dirt bikes and similar engines
- Broad engine compatibility notes in listing
TC-Motor NC250 Timing Chain For 250cc Dirt Bikes
The NC250 timing chain is designed for Zongshen ZS177MM 250cc engines, under the 7x100L configuration. This chain size is common on a variety of 250cc dirt bikes and pit machines, including models used by brands like BSE, Kayo, Xmoto, and several others in the 250cc class. The listing notes the engine family and applications where the NC250 chain is widely used, highlighting its relevance for riders upgrading or replacing worn timing components on mid-to-large displacement motorcycles. Installation should be performed with attention to timing marks and proper tensioning to maintain precise valve timing.
Practical considerations include ensuring correct link count and compatibility with existing tensioners and guides. For riders upgrading to a 250cc platform, the NC250 chain offers a balance of durability and compatibility across a broad ecosystem of engines. Always verify engine model and year to confirm exact fitment before ordering.
- 7x100L configuration
- Fits ZS177MM 250cc engines
- Widely used across multiple 250cc models
Buying Guide
Key purchase considerations
When shopping for a timing chain for a dirt bike or ATV, key factors include chain length (links) and pitch, engine displacement compatibility, and whether the chain is intended for timing or drive use. Timing chains must align with the engine’s camshaft profile and tensioning system. Consider the following:
- Engine compatibility: Verify the exact model, displacement, and year to ensure the chain’s link count and pitch match your engine’s timing requirements.
- Chain type and purpose: Use a timing chain specifically designed for the camshaft, not a drive chain. Check for tensioner compatibility if your bike uses oil-pressure or mechanical tensioners.
- Durability and materials: Look for robust steel construction and heat resistance. Some chains come with protective packaging to guard against shipping damage.
- Installation considerations: Align timing marks accurately, verify chain tension, and consult service manuals for torque and timing procedures.
- Availability and compatibility: Aftermarket chains vary in fitment across brands; ensure you have the right guides, guides, and gaskets if needed.
Comparisons By engine size
- 50cc–125cc engines: Many 84-link or 62-link timing chains with 25H pitch fit common Chinese-brand ATVs and dirt bikes; verify exact model fitment and tensioning requirements.
- 140cc–150cc class: Chains around 90 links are common, with compatibility depending on the specific engine family (YX Piranha, GPX, Honda CRF110 variants, etc.).
- 250cc class: Longer chains such as 7x100L are typical for Zongshen and related 250cc platforms; confirm with the engine code (ZS177MM, etc.).
Maintenance and usage considerations
Regular inspection of the timing chain, tensioner, and guides helps prevent timing misalignment and potential engine damage. Replace a worn chain promptly to maintain performance and avoid costly repairs. For off-road racing or heavy use, consider OEM-equivalent chains from trusted brands to ensure consistent performance under heat and vibration. Documentation and packaging should be checked to ensure the chain is suitable for your model and ride style.