The disassembly and maintenance of the central axle

Today’s time to tell you about the disassembly and maintenance of the central axle.


The disassembly and assembly methods of the square hole bottom bracket and the splined bottom bracket are almost the same. The first step is to disassemble the chainring. Tooth plate teeth.

Use a crank removal wrench to remove the crankset fixing screw counterclockwise, screw the bike crank remover tool into the crank screw hole, hold the crank and rotate the handle of the crank removal tool clockwise, if there is no handle, use a wrench instead, let the removal tool shaft Press the bottom bracket to loosen the crank, and remove the chainring downwards. At this time, avoid the chain pulling the front derailleur.

When removing the other side of the crank, be careful not to damage the crankset and crank threads during the removal process. The left and right threads on the left and right sides of the bottom bracket to remove the British threaded bottom bracket are opposite, and the left side is the forward thread. The shaft, the reverse thread on the right side should be loosened clockwise, and the left and right sides of the Italian threaded bottom bracket are forward threads, which should be loosened counterclockwise.

When disassembling, first remove the left one. When disassembling, first unscrew it and do not completely remove it. Unscrew the right side and then remove it together on both sides. When installing, you must distinguish the left and right sides. Generally, the larger central axis body is the right side, and the larger is the right side. The small one is on the left side. Lubricate the thread diagram of the central shaft, which will make the operation easier and not easy to damage the thread.

When installing, first install the right center shaft, turn it counterclockwise to tighten it, but do not tighten it slightly to fix it, then install the left side, use the tool to screw the right side to the center shaft and the plane of the bottom bracket, and then tighten the left side , hang the chain on the bottom bracket position to prevent leakage, and then install the chainring back to the bottom bracket.

So when should the center axle be maintained? Generally, the central axis finds that the abnormal noise resistance is too large, and the central axis needs to be maintained. Its maintenance generally refers to cleaning the internal bearings or balls and adding butter. If the bearing balls or other rolling accessories have When the wear is serious, it should be replaced.

Before maintenance, carefully use the bike crank puller remove the bearing on the central shaft, and then gently lift the dust cover of the bearing with a sharp taper. Be careful not to damage the dust cover. If you find that there is only a lack of butter, you can add it directly. If impurities are found, it can be cleaned with kerosene or gasoline. If the inner and outer rings of the bearing are found to be loose, it means that they should be replaced due to wear and tear.

Today’s sharing is here!

Post time: Mar-29-2022