Two chains may look like needless complication, but on the Buffalo Bicycle Utility S2 they serve a specific purpose: a simple two-speed drivetrain for cargo and demanding utility riding, shifted by pedaling backward rather than by operating a handlebar lever. The design trades the familiar derailleur-and-cable setup for two separate chain paths and a limited choice of gears.
What bike has two gears and two chains?
It is the Buffalo Bicycle Utility S2. Buffalo Bicycles describes it as a back-pedal two-speed with two chainrings, two separate chains and no shifting cables. Ars Technica reports that the drivetrain design involved SRAM engineers, who recommended the two-chain arrangement after trying simplified internal gear hubs and derailleurs.
The goal is not to provide a wide range of ratios like a multi-speed derailleur bike. It is to offer a lower climbing gear and a higher cruising gear while avoiding a derailleur, shift cables and a handlebar shifter.
How does the back-pedal shifting work?
According to Ars Technica’s explanation, the rear freewheel has two cogs, one for each gear path. Pedaling backward about half a rotation engages or disengages the outer, higher gear. The chains, chainrings and cogs continue moving, but only one gear path transmits the rider’s effort at a time.
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#1 Best Overall
- 【Package Includes】- The kit includes 1 set single speed chain, 1pcs bike link plier with hook, 1pcs chain breaker and 3 pairs of bicycle chain buckle, they are efficient, accurate matching and labor-saving.
- 【High-quality Material】- Our bike chains are made of special forging steel which is repeated forged and strict controlled of materials to ensure the strength. The are full plating silver to anti-rust, high cost performance, anti-corrosion, wear-resistant and durable.
- 【Double × Bridge Design】- Double X bridge design of the bike chain kit improves the tensile, torsional strength of the chain and have variable speed fluency improvement.
- 【Easy to Install】- The bike chain is easy to install, you can determine the length of your chain according to the original chain, cut out the length you want with a chain cutter, and install the chain with a chain hook.
- 【Wide Application】- The bike chain kit is suitable for all brands of single speed bikes, you can use it as a replacement chain while cycling.
That description explains the intended operation; the available sources do not provide independent measurements of shifting performance or drivetrain efficiency.
Why can two chains suit a utility bike?
Fewer exposed shifting parts
A derailleur system depends on a derailleur and shift cables to move the chain between cogs. The S2’s stated design removes those shifting components. For a bike intended for daily travel, cargo and demanding conditions, fewer exposed shifting parts may make roadside troubleshooting more straightforward. That is a design rationale, not proof that every repair is easier or that the bike cannot fail.
Rank #2
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- 【Widely Use】 The chain lock is 2.72 ft long, enough to lock 3 bikes together, ideal for bicycles, bike, ebikes, scooters, skateboards, motorcycles, ladders, lawnmowers, gates, fences, tool boxes, bbq, sport equipment and many others against theft.
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A possible fallback if a chain breaks
Ars Technica describes the two-chain layout as allowing the rider to continue using the other chain and cog if one chain breaks. That offers a potential fallback, not a guarantee: a failure could still leave the bicycle unusable, depending on what breaks and the condition of the remaining drivetrain.
Built around cargo and utility trips
The bike’s purpose helps explain why its designers prioritize a practical pair of ratios over a broad gear range. Ars Technica reported a 200-pound rating for the rear rack. That figure is the rack rating reported in its February 4, 2025 article, not a statement about total bicycle capacity or a guarantee of safe loading in every use.
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- Package Includes: The kit includes 1 set 6/7/8 speed chain, 1pcs bike link plier with hook, 1pcs chain breaker and 3 pairs of bicycle chain buckle, they are efficient, accurate matching and labor-saving.
- High-quality Material: Our bike chains are made of special forging steel which is repeated forged and strict controlled of materials to ensure the strength. The are full plating silver to anti-rust, high cost performance, anti-corrosion, wear-resistant and durable.
- Double X Bridge Design: Double X bridge design of the bike chain kit improves the tensile, torsional strength of the chain and have variable speed fluency improvement.
- Easy to Install: The bike chain is easy to install, you can determine the length of your chain according to the original chain, cut out the length you want with a chain cutter, and install the chain with a chain hook.
- Wide Application: The bike chain kit is suitable for 6-speed, 7-speed, 8-speed road and mountain bikes. It is suitable for shimano and SRAM variable-speed systems.
What are the trade-offs?
The S2 has two gear choices, not the many ratios commonly offered by a derailleur drivetrain. It also has two chains and two gear paths to maintain. Whether that is an advantage depends on the rider’s priorities: a simple shift mechanism and a possible chain-path fallback may matter more than a wide range of ratios, while riders who want conventional shifting or easier access to familiar replacement components may prefer a different setup.
The available sources do not establish comparative efficiency, chain-wear balance, maintenance intervals, long-term durability or controlled performance against derailleur drivetrains or internal gear hubs. The design should therefore be understood as a specific solution for utility use, not as a proven reliability or longevity improvement over other bicycle gearing.
Rank #4
- 【6/7/8 Speed Chain】- Package includes 1 set 6/7/8 speed bike chain, whose size is 1/2×3/32 inch, the bike chain has 116 links, you can adjust length according to the length of your bike chain.
- 【Double X Bridge Design】- Our bike chain adopts double X bridge design, which improves the tensile, torsional strength of the chain and variable speed fluency.
- 【Special Forging Steel】- 6/7/8 speed bike chain is made of special forging steel which is repeated forged and strict controlled of materials to ensure the strength. Full plating sliver is anti-rust, anti-corrosion, wear-resistant, high cost performance and durable for use.
- 【Easy to Install】- The bike chain is easy to install, you can determine the length of your chain according to the original chain, cut out the length you want with a chain cutter, and install the chain with a chain hook. NOTE: chain cutter and hook is not included.
- 【Wide Application】- Bike chain is suitable for 6/7/8 speed mountain bike chain, road bike and other bikes, and it is suitable for foldable bikes, BMX, etc.
What is known about the S2 beyond its drivetrain?
Buffalo Bicycles says the design won Eurobike Award Gold in 2024 and displays US Patent 11,655,004 on its About page. These are manufacturer-reported claims. The company’s utility-bike mission is consistent with World Bicycle Relief’s broader work to expand access to education, markets, healthcare and other services through bicycle mobility, in collaboration with communities and institutional partners.
Sources: Buffalo Bicycles, About Us; Ars Technica, February 4, 2025; World Bicycle Relief.
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Quick Recap
Best Value
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- 【Easy to Use】 This bicycle chain tool set is well-made and easy for beginners to use, making your bicycle maintenance process more convenient. If you don't mind gaining a sense of accomplishment through self-repair, this tool set is definitely worth a try
- 【Multi-Function Chain Pliers Tools】 With their ergonomic design, these pliers make gripping, bending, and securing chain links exceptionally effortless and comfortable. Whether installing or removing master links, operations are quick and intuitive, streamlining the repair process. They enable faster, more straightforward maintenance—easy to master and designed to save you time and effort
- 【Quick and Easy Assessment】 This set of bicycle chain checkers allows you to quickly provide simple and fast evaluations at 0.75% and 1.0% wear thresholds, helping prevent unexpected chain breakage, ensuring optimal performance, and extending the chain's lifespan
- 【Compact and Portable】 Whether you are a cycling enthusiast or a beginner, this bicycle chain repair kit is an essential tool. Its compact and lightweight packaging can fit into any saddlebag, allowing you to easily take it out and make repairs if your bike breaks down on the road, so you can get back to enjoying your ride in just a few minutes
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