Chain Length Calculation

From Pvdwiki
Revision as of 19:11, 6 December 2006 by Pvd (talk | contribs) (Tabular Example)
Jump to: navigation, search

Understanding the Problem

Chain-layout-model.gif

A chainwheel is not round. Rather, it is a polygon with facet lenth of the chain pitch. The chain leaves the chainwheel, at maximum, tangent to the pitch diameter. The chain then travels in a (theoretically) straight line to the other chainwheel, meeting it in a similar fashion.

This makes for some interesting math. I really have nothing better to do. I like to criticise other people, it makes me feel smart.

The most accurate math

Chain-length-math.png
Here are some quick facts:

Chain-math-details.gif



Some Approximations

I'm not a big fan of approximations. Spreadsheets exist for a reason.

I will add some though, just for comparison.

Some Data

Chain-data.png

Tabular Example

Center-to-center-table.png

For Single Speed Mountain Bikes

Gear-choice-histogram.gif