--- product_id: 267964920 title: "Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine" brand: "sthus" price: "€ 42.58" currency: EUR in_stock: true reviews_count: 5 category: "Sthus" url: https://www.desertcart.hr/products/267964920-black-spring-loaded-chain-tensioner-for-49cc-66cc-80cc-engine store_origin: HR region: Croatia --- # Adjustable chain tightness Spring-loaded precision tension Durable metal construction Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine **Brand:** sthus **Price:** € 42.58 **Availability:** ✅ In Stock ## Summary > ⚡ Keep your ride tight, smooth, and unstoppable! ## Quick Answers - **What is this?** Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine by sthus - **How much does it cost?** € 42.58 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/267964920-black-spring-loaded-chain-tensioner-for-49cc-66cc-80cc-engine) ## Best For - sthus enthusiasts ## Why This Product - Trusted sthus brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Customizable Ride Comfort:** Easily adjust tension to your preference for a smoother, vibration-free cycling experience. - • **Effortless Chain Stability:** Spring-loaded design keeps your chain perfectly tensioned, eliminating annoying pops and snaps. - • **Extended Component Lifespan:** Reduces wear on your chain and nylon tension wheel, protecting your investment over time. - • **Quick & Simple Installation:** Designed for center or rear mount setups, making upgrades hassle-free and fast. - • **Universal Fit for 49cc-80cc:** Compatible with 49cc, 66cc, and 80cc motorized bike engines—versatility that matches your ride. ## Overview The sthus Black Spring Loaded Chain Tensioner is a robust metal component engineered for 49cc to 80cc motorized bikes. Its spring-loaded mechanism ensures optimal chain tension, preventing chain slippage and reducing vibration. Adjustable for personalized tightness, it extends the lifespan of your drivetrain parts while delivering a smoother, more reliable ride. ## Description Description:Chain Tensioner Spring Loaded For 49cc 66cc 80cc Engine Motorized BikePackage Include: 1 x Chain Tensioner KitSpring loaded chain tensioner that keeps chain from popping and snapping. Can be used for all chain drive applications including center mount and rear mount chain drive for gas motorized bicycle plan kits. Must be mounted so that it pulls on the chain so the spring action will work effectively keeping the chain tight, but not too tight.Spring loaded installation positions on bicycle so the spring pulls on the chain. Can also be placed on the lower chain. The amount of tension can be adjusted to your liking. Remove vibration and snapping and popping of the chain during operation. It also keeps the nylon tension wheel from wearing out.This makes for a smoother, more enjoyable ride without vibration and increases the lifespan of not only the chain, but motorized bicycle parts. Makes the whole bike, motor and everything else last longer, because you aren't shaking it excessively. It really makes the difference between enjoying your ride and being glad that it was over. Review: The best! - I struggled with many chain tensioners thinking ok i got it this time...? Dont kid yourself.. spring-loaded tensioners are the best solution for sure! The one thing I needed to do.. I grinded the bolt heads down about half.. so crank peddle can pass freely.. Use double nuts on the bolt harnessing flex part, to lock tight but still loose enough for tensioner to flex.. Thats it.. Works great! Review: Good parts 100% - Works as it should excellent would buy again ## Features - For Chain Tensioner Spring Loaded For 49cc 66cc 80cc Engine Motorized Bike - Package Include: 1 x Chain Tensioner Kit - 80cc bike chain tensioner - motorized bike chain tensioner - International products have separate terms, are sold from abroad and may differ from local products, including fit, age ratings, and language of product, labeling or instructions. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B07NXX4PV4 | | Brand | sthus | | Customer Reviews | 4.1 out of 5 stars 2,433 Reviews | | Item Length | 45 Inches | | Item Weight | 300 Grams | | Item length | 45 Inches | | Load Capacity | 2.5E+2 bis 500 N | | Load capacity | 2.5E+2 bis 500 N | | Manufacturer | sthus | | Manufacturer Part Number | AMWZ_MZ0052-1 | | Material | Metal | | Model Number | AMWZ_MZ0052-1 | | Recommended Uses For Product | Maintaining proper chain tension in motorized bikes with 49cc, 66cc, and 80cc engines | | Recommended uses for product | Maintaining proper chain tension in motorized bikes with 49cc, 66cc, and 80cc engines | | Strand Type | Multiple | | Strand type | Multiple | | Unit Count | 1.0 count | ## Product Details - **Brand:** sthus - **Item length:** 45 Inches - **Load capacity:** 2.5E+2 bis 500 N - **Material:** Metal - **Recommended uses for product:** Maintaining proper chain tension in motorized bikes with 49cc, 66cc, and 80cc engines ## Images ![Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine - Image 1](https://m.media-amazon.com/images/I/616OeX7TnCL.jpg) ![Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine - Image 2](https://m.media-amazon.com/images/I/71kCiVxZZEL.jpg) ![Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine - Image 3](https://m.media-amazon.com/images/I/71yTr3Q1GnL.jpg) ![Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine - Image 4](https://m.media-amazon.com/images/I/81Q5vsZNxYL.jpg) ![Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine - Image 5](https://m.media-amazon.com/images/I/81aG33ZWzLL.jpg) ## Questions & Answers **Q: Will this work on a go cart?** A: Depending on the length of the chain an if it will mount to the 2 stroke engine **Q: Replacement wheels come in 8mm&10mm which size do i need for the black Sthus tensioner?** A: That's an odd question. The standard chain for a bike motor kit is #415 which is 7/16" wide or a little more than 11mm; neither of those sizes would work. If it is a replacement wheel then I would propose measuring the one you have to determine how big it is. If the wheel is actually a sprocket then 8mm would work with conventional #415 chain as the inner spacing between the outer bone links of the chain is 8mm. **Q: Can you use the stock chain guard, that comes with the motor, with this tensioner?** A: The stock chain guard and this tensioner can coexist on your bike without issue. **Q: Can these chain tensioners be used to tighten drive belts? I am converting to belt drive .** A: Yes, the pulley is 1" wide, so as long as the belt is not wider than an inch it will work. ## Customer Reviews ### ⭐⭐⭐⭐⭐ The best! *by W***M on 22 September 2023* I struggled with many chain tensioners thinking ok i got it this time...? Dont kid yourself.. spring-loaded tensioners are the best solution for sure! The one thing I needed to do.. I grinded the bolt heads down about half.. so crank peddle can pass freely.. Use double nuts on the bolt harnessing flex part, to lock tight but still loose enough for tensioner to flex.. Thats it.. Works great! ### ⭐⭐⭐⭐⭐ Good parts 100% *by B***R on 9 April 2026* Works as it should excellent would buy again ### ⭐⭐⭐⭐ cheap hardware *by J***E on 24 March 2026* everything fits good. my only problem is the cheap hardware. 1 bolt the threads all stripped off, and also the heads catch on my pedals. so i have to go to the hardware store and look for a couple better bolts. not a big issue. also the plastic roller wheel seems rather cheap, not sure how long its gonna hold up. for the price i guess it was worth it. ## Frequently Bought Together - sthus Black Spring Loaded Chain Tensioner For 49cc 66cc 80cc Engine Motorized Bike 2 Stroke Engine - JRL 32mm-40mm Black Offset Intake Manifold and Gasket for 49cc 66cc 80cc Motorized Bike Motorised Bicycle (Black) - IMAYCC Bike Motor Kit 80cc Motorized Bike Kit 2 Stroke Bicycle Engine Kit with Wired Digital Computer Fit for 26-28" Bikes --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.hr/products/267964920-black-spring-loaded-chain-tensioner-for-49cc-66cc-80cc-engine](https://www.desertcart.hr/products/267964920-black-spring-loaded-chain-tensioner-for-49cc-66cc-80cc-engine) --- *Product available on Desertcart Croatia* *Store origin: HR* *Last updated: 2026-06-10*