battery operated bicycles disc repair

Determine runout is caused by what . Inspection methods: support from a large front wheel off the ground , light hand turn the wheel, find much resistance areas. That point grinding disc , battery powered bicycles marked with a red marker . And in the three bolts marked 1,2,3, serial number , and remember the original installation location.
1 , remove the front wheel . Then remove the battery powered bikes disc . This is the most troublesome , is a bit difficult , screwing the bolt must be struck with a hammer in front of three hexagonal , or hexagonal plate wring also screwed down.
2, the discs get clean , put on a clean glass , the disc without side down stairs . With a thin piece of paper next to the hard disc plugs, as are stuffed into, explained the disc is not deformed , said Mingrui face runout caused by the wheels .
3 , the Electric Bicycles disc must be relatively flat deformation . This is not difficult , you have friends in the machine shop of the most easy.
4 Wheel Swiss uneven surface will use the compensation method . That method in 1.2.3 plus sheet position among the added sheet , the sheet is cut into the skin of cans ( thickness 0.12MM). Combination of the above grinding disc plus point to determine the location of the sheet , depending on everyone's analyzes .