Thursday, 7 June 2012

Sunday, 9 October 2011

Stack & Reach Calculator v1.00

Hi, thanks for visiting! I made this simple stack and reach calculator because I couldn't find one that suited my needs online. Hope you find it useful!

How to use?
  1. The spreadsheet can calculate stack and reach either with standard geometry info or stack and reach info if known. Just open it in full screen and enable edit. If you mess up, just refresh the page.
  2. Use the calculator on the left when using standard geometry. Fork length and rake is required for accurate results. Please see comments in the spreadsheet for details.
  3. You can also calculate fork length or rake if you know one or the other as well as the stack and reach, through trial and error. Just fiddle with it and you'll figure it out.
  4. Use the calculator on the right if stack and reach is known.
If you have any comments or suggestions, please leave them below, thanks!

Measuring Effective Top Tube & Fork Length

The calculator works well with Focus Bikes data for example, as they measure the effective top tube (ETT) and fork length (FL) as I would. As seen in the Focus Izalco geometry table: ETT is measured from top of head tube C-C and FL from axle to bottom of head tube C-C.


Other companies measure ETT differently. Cervelo measure slightly below the head tube, along the center axis of the virtual top tube.


The calculator does not account for the difference in measuring the ETT. It can be calculated, but difference tiny, less than half a millimeter. And there's no difference if the seat tube angle and head tube are parallel.