MRELC 420 Jackshaft & Roller Chain Kit 42-Link + 90-Link with Chain Breaker — Alloy Hardened, Trim-to-Fit for 196–212cc Mini Bikes

This complete chain kit supplies the short 42-link jackshaft chain and the long 90-link standard 420 roller chain needed by many Coleman, Baja, Massimo, TrailMaster and similar mini bikes, along with practical tools and connectors so you can install, shorten, or maintain the drive system without extra parts. Every chain is built from alloy steel with surface hardening for greater wear resistance and corrosion protection, and the kit includes a portable chain breaker and tensioner adjusters so you can size the chains on the bench or in the field.

What exactly is included and why does each part matter?

The kit contains a 42-link 420 jackshaft chain, a 90-link 420 roller chain, a 420 chain breaker, ten connector links, and two tensioner adjusters. Together these items let you install, trim, and secure both drive chains used on many mini bikes without searching for individual components.

• 42-link jackshaft chain: shorter drive chain for jackshaft-to-sprocket connection.
• 90-link roller chain: longer primary chain for engine-to-jackshaft drive.
• Chain breaker: remove or shorten links for custom fit.
• Connector links (x10): reliable reassembly points for quick repairs.
• Tensioner adjusters (x2): set correct chain tension to prevent slipping or premature wear.

How does the kit fit my Coleman, Baja, or Massimo mini bike?

The 42-link and 90-link sizes match the jackshaft and primary drive lengths used on many popular mini bikes like Coleman CT200U, CT200U-EX, BT200X, Baja Warrior MB200 and Massimo MB200. The chains are supplied long enough to trim down to fit machines with similar sprocket combinations.

• Compatible brands: Coleman Powersports, Baja Motorsports, MASSIMO, TrailMaster and several Hensim/Tomberlin models.
• Fits engines in the 196–212cc and 6.5hp range commonly found on these mini bikes.
• Trim-to-fit design: use the included chain breaker and connectors to size the chains precisely.

What are the performance and durability features of the chains?

Both 420 roller chains are manufactured from alloy steel with strict material control and a hardened surface finish to increase service life under load and resist corrosion in outdoor conditions. The roller design reduces friction and distributes wear evenly across pins and plates.

• Alloy-steel construction for higher tensile strength and fatigue resistance.
• Hardened surfaces to delay wear on sprockets and rollers.
• Standard 420 pitch for widespread sprocket compatibility.
• Easy to clean and maintain to extend service intervals.

How do the tools in the kit simplify maintenance and repairs?

The included chain breaker lets you split or shorten a chain without needing a dedicated workshop press, while connector links and tensioner adjusters make reinstalling and adjusting chain length quick and repeatable. These tools are compact and suited for roadside fixes or garage work.

• Portable chain breaker supports many 420-type chains for field repairs.
• Connector links enable fast reconnection after sizing or damage repair.
• Tensioner adjusters allow micro-adjustments to prevent slapping or binding during rides.

Who is this for: This MRELC kit is aimed at mini bike owners, backyard mechanics, and small-powersports repair shops that need a practical, all-in-one replacement for worn or broken 420 chains on Coleman CT200U/BT200X-style machines, Baja and Massimo mini bikes, and other 196–212cc 6.5hp class vehicles. If you want to perform chain replacement or field repairs without sourcing separate parts, this set gives the chains, the connectors, and the tools needed to get back on the trail quickly.