Tire pressure is definitely one of the most overlooked aspects of race day setup. Typically most athletes pump to the same pressure they ride every other day and off they go. But that is not only wrong – but hugely detrimental to your race time. Silca – and specifically their owner Josh Poertner has been preaching the benefits of proper tire pressure since he was leading engineering teams at Zipp. But until now it’s still been a bit of black magic to us common age groupers – it was up to us to figure out which was the proper pressure for any given race day. Silca’s new Professional Pressure Calculator has turned black magic into science.
The Silca Professional Pressure Calculator
Silca has spent the past few years amassing what is considered by most to be the largest collection of data in the world of tire size, pressure, rider weight, and course. From this data, the team at Silca has developed a tire pressure algorithm which fits more than 4000 optimal pressure data points from more than 100 athletes on more than 90 ProTour, Triathlon, CX and Gravel races worldwide. And now it is ours to share in.
To start head on over to https://info.silca.cc/silca-professional-pressure-calculator. Fill in your name, email address, and rider type (because everyone needs an email list).
Next come more specifics about your setup and race day conditions.
A couple of notes on this. First off the weight is you AND your bike (including all the accessories and nutrition you plan on putting on it). Yes that means even you weight weenies who think they have the lightest bike around. Make sure you still factor that in. Either weigh yourself and the bike separately and add them together. Or just hold your bike on the scale. We also recommend using the weight you expect to be on the bike (don’t use the weight you tell your spouse after you remove five pounds because you had a heavy lunch).
Second is the actual measured tire width of the tire. Silca has a great blog post on tire width and the impacts of printed width versus actual (https://blog.silca.cc/tire-size-pressure-aero-comfort-rolling-resistance-and-more.-part-1-how-we-got-to-now) and the impact of different sized rims. The image below (which we hope they don’t mind we borrow) shows just how much of an impact rim width can have on the tire itself.
Regarding road surfaces – we also recommend you take a moment to read https://blog.silca.cc/part-4b-rolling-resistance-and-impedance. It shouldn’t be a huge surprise that road surface has a huge impact on rolling resistance – but the science is still fascinating.
And when you have the form all filled out you will get something like this:
Now our one big note here is that we have yet to take the recommended tire pressures for a spin. And they are definitely less than we have ridden previously. The good news is that we have the entire off season to get some ride time on them and get comfortable with them. Let us know what the computer spits out in the comments below (or on Facebook). And as always thanks for reading AeroGeeks.com.