Resolved Question
Show me another »What are the ball bearings in a bike(bmx)?
My friend has lost the ball bearings in a his bmx, i was wondering, were the go, what they are, how to fit them, were to buy(not important), what affects they have on the bike, what they do?
Best Answer - Chosen by Voters
Ball bearings are used where two parts are joined and need to stay fixed together but also allow one part to rotate inside the other part. Wikipedia has an excellent write up and illustration of how they work. The ball bearings are literally small, metal balls, and there is a track (called a "race") that they follow as the pieces rotate and the balls turn.
Ball bearings are used in bikes in the bottom bracket (crank), pedals, hubs (wheels), and headset (stem/handlebars). If these parts are adjusted and greased correctly, the parts can turn very smoothly and freely but be held firmly in place. For example, cranks can turn in a nice circle but not move side to side at all. If the bottom bracket bearings are tightened too much the cranks no longer turn freely, and if they aren't tightened enough the crank arms can wobble side to side a little.
Ball bearings come in all sizes from a tiny pebble size to baseball size. A diameter of 1/8-3/16 inch is roughly the size of most ball bearings in bikes.
Ball bearings are used in bikes in the bottom bracket (crank), pedals, hubs (wheels), and headset (stem/handlebars). If these parts are adjusted and greased correctly, the parts can turn very smoothly and freely but be held firmly in place. For example, cranks can turn in a nice circle but not move side to side at all. If the bottom bracket bearings are tightened too much the cranks no longer turn freely, and if they aren't tightened enough the crank arms can wobble side to side a little.
Ball bearings come in all sizes from a tiny pebble size to baseball size. A diameter of 1/8-3/16 inch is roughly the size of most ball bearings in bikes.
Source(s):
100% 2 Votes
- Action Bar:
- 0 stars - mark this as Interesting!
- Comment (0)
- Save
There are currently no comments for this question.
* You must be logged into Answers to add comments. Sign in or Register.
Other Answers (3)
- There are ball bearings in the cranks, the pedals, the hubs, the headset, possibly the derailleur pulleys. Some shifting mechanisms have ball bearings in the pivots, and some brake calipers as well. Ball bearings reduce friction anywhere something spins. They come in several different sizes. They rarely "just fall out" if they are lost, often some other part is damaged as well, if for example a wheel continues to spin without ball bearings, the hub can be so badly damaged that it would have to be replaced which usually means buying a whole new wheel.0% 0 Votes
- They will be either in the wheels or the crank. Have them replaced professionally, Especially if they are in the crank as you would need a crank extractor to remove it.
It shouldnt cost more than £10 if it is just the bearings
Ball bearings help the wheels turn smoothly on the spindle and help prevent wearing. Pretty much the same on the crank0% 0 Votes -
Open Questions in Cycling
Answers International
- Argentina
- Australia
- Brazil
- Canada
- China
- France
- Germany
- Hong Kong
- India
- Indonesia
- Italy
- Japan
- Malaysia
- Mexico
- New Zealand
- Philippines
- Quebec
- Singapore
- South Korea
- Spain
- Taiwan
- Thailand
- United Kingdom
- United States
- Vietnam
- en Español
Yahoo! does not evaluate or guarantee the accuracy of any Yahoo! Answers content. Click here for the Full Disclaimer.
Help us improve Yahoo! Answers. Send Feedback
Copyright © 2010 Yahoo! Inc. All Rights Reserved.