SpokeCalc has been designed to simplify the use of a spoke calculator to a common, first time user as you will find it in the following tutorial. So let’s see what features are available in SpokeCalc.
CHOOSE A WHEEL
First step is to navigate to the proper wheel you are trying to get spoke calculations for. If you are calculating for the front wheel, make sure you enter measurements under appropriate section. On desktop you have separate sections for each wheel side by side while on smaller, mobile screens you will notice tabbed menu like one on the image below. This is important as the calculator’s algorithm differs between front and rear wheel when including measurement of OSB (for asymmetric rims).
The very next thing, that is important, is to specify the type of the hub you will be using by selecting it from the checkbox like shown below. Classic hubs use J-bend spokes, while the straight pull hubs like the name suggests use completely straight spokes.
Now we come to the most interesting part, entering measurements. I have prepared some great features to help you here. First of all, by all means, do use tooltips (the white icon with character “i” in it) to trigger popup window with helpful imagery. Under these tooltip images, you will here and there find also ‘’Note: “ with some useful advice regarding this particular measurement.
In each input window you will also find appropriate unit reference. In general all sizes should be in millimetres! When entering decimals, please note that you must use DOT (.) and not comma. If in doubt about how to take measurements, please refer to my article on this subject. Precise calculation always depends on precise measurements you take of your wheel setup. You will find that sometimes you cannot only depend on data, found on the internet.
While we are covering filling out the inputs, it is normal for mistakes to happen. Therefore I have implemented two types of validation. One is non-intrusive and happens immediately after you enter a value. You will be warned as you go if you enter wrong value for example text, number that is out of range or you just forget to fill it out. Something like that:
See the difference? Rim ERD’s obviously isn’t in the expected range and so the input will be styled with white bottom border and a little saturated background. Other type of validation is much more noticeable and appears after the click on Calculate button. You will get popup window with the problem input stated:
Once you enter measurements and move to the last accordion, where you choose lacing pattern, the "CALCULATE" button should appear on your mobile screen. Before that you won’t notice that button whatsoever.
When you click on calculate button, you should notice calculations for left (non-drive side) and right (drive side). Right side is the one where your drivetrain is mounted. On your mobile these two fields should just pop up from the bottom. These are initial calculations, but there is more information available when you click on the graph icon below.
Once you do a calculation for one wheel you can easily calculate the second wheel without the risk of losing any data about the first one. In that way you can preview the whole wheelset setup and tweek the data to get different values or compare it with other setups.
You will also notice a RESET button underneath the main calculator section. When in need of a new calculation and you want to delete previously used values, just press this button and it will leave you with empty inputs.
Most of you will probably end with the initial calculations as arguably it is the most important output of this spoke calculator. However you can continue by clicking on this graph icon and your wheel’s setup will show with in great detail.
Here you will find your input data stored in a table, spoke length for both sides and below even some tensioning references. Compare different setups' specifications by mixing and matching different components or by just printing out the wheel setup sheet. Give it a try!
Do you have any more questions? Please refer to my FAQ page in the main menu or leave me a comment on firstname.lastname@example.org