Gear ratio calculator
Last update:  6/2/2015  Return to top of home page  
Return to home page links    

Start spreadsheet

For the preset time you will need to have Microsoft Excel installed on your computer to be able use this calculator. Sorry 'bout that.  I believe that Open Office will also work with the XLS file.  I will try to set the spreadsheet up in "google sheets" when time permits.

The spreadsheet was set up with  Excel 2000 and should also run on all versions.  In order to have some basic data in the spreadsheet for each user to start with and to prevent changes to the formulas I have locked the file except for several cells on the left side of the sheet that you can input your data into.

General information:
If you have Excel you will see a typical spreadsheet with various colored columns etc when you click on the Start spreadsheet button.  Please read the Notes to get familiar with what the various colors stand for.  The pinkish cells that you can input your data have a message window that opens with a short help message when the cursor is on the cell.

Each time the spreadsheet is started it will be set up for my 6 speed GSXR-1000 transmission using a RX-7 rear end with 3.933:1 gear ratio. I have included several popular rear end gear ratios, 3.308, 3.450, 3.540 in addition to the GSXR (2.470:1) and RX-7 (3.933:1) ratios to give you some ratios to compare your data with.

As you enter your transmission gear ratios you will see the output data under the various columns change.  The data field titled "MPH in top gear" is based on the 6th gear ratio.  If you don't have 6 speeds just enter the ratio of your top gear in cell D12  in the "Transmission ratios" field.

You can not save the spreadsheet as a XLS file to work with on your computer later.  For now it can only be run from this website.  You can save the sheet as a HTML file using the normal Excel [File, Save As] command.  If you don't save the spreadsheet the resulting data of your inputs will not be saved if you reopen the spreadsheet from here later.