Sooner or later, every bike will need a new chain and sprockets. Once a chain begins to wear, its pitch changes and wears the sprocket teeth. Then the chain begins to wear even faster. Then it's time for a new chain, and a new pair of sprockets. The rear wheel on my motorcycle had been misaligned (I had used the inaccurate etched indicators on the swingarm-rather than a ruler against the sprocket-to set wheel alignment) and ridden hard through a gritty, salty winter. The rear sprocket was in rough shape, and the chain was making lots of popping sounds as the bike went down the road. Changing a chain is a fairly basic job that requires a chain breaker / riveting tool and whatever is needed to remove the rear wheel and sprockets. It's nice to have a blow torch and a torque wrench on hand for this job, too. The ingenious Terra-X chain tool is made in Australia out of tool steel, and weighs just 150 grams. A big hollow bolt threads into the bigger of the two holes, and is used when pressing outer plates onto new master links. A smaller bolt with a pin can thread into the hollow bolt, and is used to push link pins out of old chains or to peen new master link pins by pushing them against a grub screw threaded into the steel body's other hole. That little grub screw with a rounded steel end screws into the smaller hole of the chain breaker. It fits into and peens the hole of the new master link. When changing a chain, the first step is to loosen the bolts on the front sprocket. It's good to get those loose while the chain is still on the bike, partly to avoid putting undue stress on the transmission, and partly to avoid getting deep into the job and finding that the front sprocket bolts are stuck. In this case, the small allen bolts needed a bit of heat to come undone. After the bolts are loose, it's time to break the chain. With the Terra-X chain tool, you remove the small grub screw and use the small bolt with the pin to push out one of the chain's pins. No grunting or swearing required. Then comes sprocket replacement. Six nuts on the rear sprocket, the two bolts on the front sprocket, and that step is done. I had a torque wrench handy, so I could get the torque values just right when putting everything back together. The next step is the big one: installing the master link that joins the ends of the new chain together. The master link comes with a little bag with some X-Rings, a master link, and some sticky tan lube. Smear the lube on the pins and inside the X-Rings, then begin to assemble the master link around the two ends of the chain, making sure to get the X-Rings in the right spots. Pressing the outer plate onto the master link is the hardest part of the job. I removed the pin bolt from the Terra-X tool and used the hollow bolt to push the outer plate onto the master link's pins. It took a few tries, but eventually I got it in the correct position. After the sprockets are on and the master link is in position, the master link's pins need to be peened. With the Terra-X, the pin bolt pushes the master link pin against the grub screw's steel ball, and flares the pin. It takes a lot of effort-mostly because it's not easy to get a lot of leverage on tools when they're underneath a motorcycle. Position the wheel for proper chain tension, torque everything to the correct specs, and you're back on the road. The new chain is smooth, nearly silent, and ready for thousands of miles of high-speed running. adjust-primary-chain-2000-fatboy-l3pkhus41ndyrzcpoepz5ks5-3-0.jpg