Review on 🚴 LEZYNE Portable Bicycle Chain Repair Tool - High-Quality Steel Chain Breaker and Joiner for Mountain and Road Bikes by Terry Paige

This tool can either break the roller chain or connect the two ends of it. Most compact tools can only push the pin out of the chain. This tool can also push the primary pin into the chain because: 1) it holds the links firmly at right angles to the cylinder. 2) When the hold down pin is removed from the cylinder, the chamfer on the end of the pin opens allowing the pin to stay in line with the pin. This is useful to start inserting the dowel. 3) Even if you don't follow my suggestion (point 2), there is enough clearance between the end of the double length primary dowel and the push pin to try to push it in. , These foldable pocket multi tools don't need chain tool with enough clearance. As a result, they can only remove pins. In fact, the holes in all four links do not match. You have to do it yourself. However, this tool will correct this alignment. It helps that its 7M piston has fine threads, minimizing torsional play. Many (probably most) other disconnect/connect tools have pistons with unacceptably coarse threads. Still, it's light enough and compact enough to pack with other essentials on a long trip. It's also all steel (not zinc or aluminum) so it's fairly durable. Although it is described on the Revain product page for use with 9 and 10 speed chains, I used it to connect the ends of a Shimano CH-. HG71 chain for 6/7/8-speed rear wheels. The bike chain of this size is one of the widest. Thus, the dowel that holds the four links and the pulley is one of the longest and most difficult to align and set in place. I used the double length breakaway that came with this chain. It is best to first remove the Lezyne push pin (unscrews from the piston) to reveal a tiny bevel that will help align the contact with the chain pin. In other words, do not use the pin of this tool to first push in the dowel. The tool's pin is best used to complete (but not begin) insertion or to push out the dowel. In addition, such use also significantly increases the life of the Let's. I'm not giving 5 stars because the design could have been better. I wish it had a spring loaded socket like Pedro's Tutto tool to align and hold the dowel (especially the new double length breakaway dowel) before pushing it in.