New answers tagged crankset
If you can't feel it with your hands, maybe you should look at the pedal. One of my pedals does similar thing. When a crank was getting loose on one of my bikes it was felt with hands too, and when coasting. Also, it may be bent chain ring or broken tooth on a chain ring.
The fault turned out to be a crippled ratchet in my rear hub. I got it replaced but am thinking of replacing my old bike now, it served me 10000Km in every season, every road in 2 years plus 3000Km in 3 years, a good service.
You should have this checked by a mechanic immediately. There are at least 4 possibilities: One of the crank arms is loose or cracked. This is the most dangerous, since a failure at the wrong time could cause you to lose control of the bike. A bearing is loose or worn out in either the bottom bracket or one of your pedals. A pedal could also fail ...
Square taper comes in subtypes: ISO (mostly Campagnolo, SA, Stronglight, some Shimano) JIS (basically everyone else) other rare types To some degree, these can be used interchangeably. However, the resulting small misfit will push the chainline in or out. Sheldon Brown covers this: http://sheldonbrown.com/bbtaper.html You can Google Velobase for all ...
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