A chain breaker tool pushes a chain pin out so you can shorten, remove, or service a chain. Align the tool’s pin with the chain pin, tighten, and turn the handle.
Whether you’re fixing a bicycle chain on the trail or sizing a new motorcycle chain in the garage, the process is the same. You position the chain in the tool, align the driving pin with the actual chain pin, and then turn the handle to press it out. Getting the alignment right is the difference between a clean break and a bent tool.
Positioning The Chain In The Tool
Start by opening the tool’s body bolt enough to slip the chain over the anvil. Place the chain so the pin you want to push out sits directly under the breaker pin. The driving pin must contact the chain pin itself, not the side plate — hitting the plate is the most common way to damage both the chain and the tool. Tighten the body bolt just snugly against the chain to hold it steady; over-tightening can crush the links.
For larger drive chains, Motion Pro’s instructions recommend grinding off the rivet heads first when breaking #520 or larger chain, which reduces the load on the tool. For standard bicycle chains, this step is rarely needed.
Advancing The Breaker Pin
With the chain held firm, turn the extractor or push bolt clockwise. Apply steady hand pressure only. One manufacturer’s instruction sheet is explicit: tighten by hand using the lever or a 14 mm wrench — no extensions, no power tools. The pin will push into the chain’s side plate, then press the chain pin out the other side.
You’ll feel resistance increase as the pin starts moving, then a sudden release when it pops free. Stop as soon as the pin is flush with or slightly past the far side plate. Over-driving the pin can bend it or damage the tool’s tip. our tested roundup of the best chain breaker tools covers which models handle heavy use best.
Releasing The Chain And Rejoining
Once the pin is pressed through, back the extractor bolt out completely to release pressure, then open the body bolt and lift the chain free. The pin will either fall out or need a gentle nudge. The chain is now separated at that link.
To rejoin, most tools double as a riveter: place the link back together, then use the tool’s opposite end to press a new pin or the existing one back through. Park Tool’s CT-3.3 instructions show this two-sided design — a breaker end and a riveting end — and note that the same alignment care applies when pressing the pin back in.
Tip Sizes And Lubrication
Using the wrong tip can damage the tool or the chain. Most kits include multiple tips; match yours to your chain’s pitch before starting. A quick look at your chain’s side plate will show the size stamped on it.
Before your first use, apply grease to all threads per one manufacturer’s guidance; another suggests a drop or two of oil on the main and inner screw threads. This keeps the action smooth and prevents wear. Motion Pro’s chain breaker instructions detail the full procedure and tip compatibility for their tools.
Work slowly, keep the pin aligned, and stop at the right moment. A chain breaker tool becomes a reliable shop staple once you trust the process — and the tools themselves are straightforward enough to last for years.
References & Sources
- Motion Pro. “08-0001 March2020 Udpate.indd” Instruction sheet covering breaking and riveting procedures plus tip size compatibility.
- Park Tool. “CT-3.3 Chain Tool Instructions.” Official manual for the CT-3.3 chain breaker and riveting tool.
- Cycle Gear. “Motion Pro Chain Breaker/Riveting Tool Instructions.” Manufacturer instructions covering hand-tightening limits and lubrication guidance.