Keeping your pressure under control

Why?

So why care about your tire pressure? There are a few reason: Punctures can be dangerous and affect riding performance, riding off-road is usually better with lower pressure and the basic fun science thing of what is going on while riding and how can it be measured. I also noted that good riders (Simon!) usually care quite a bit about their pressure while riding with them.

These days there are monitors that keep track of the pressure in a wireless way. While looking for one I did a bit of Googling and found the SYKIK Rider SRTP300 to be a popular choice. So I ordered one and it showed up a couple of weeks later.








Installation

The system is meant to be super simple to install and I expected no problems after setting up my warning levels of temperature and pressure. Off I went to the garage and installed it but things were not working as easily as every one said.






Fixing the problem

SYKIKs email support works all good and they identified that the rear sensor hadn't turned on correctly and a reinstallation i.e. remove the cap and reinstalling it should fix the problem. Such an easy fix sounded unlikely but after trying it out it all started working perfectly.








Testing it out

To test it out I took the bike for a spin over to Stanley. It is about 30 minute ride from Mid-levels so would work well for testing the system out. The display is pretty easy to read while riding and fairly interesting to see how temperature a pressure changes while riding. The key learning is that the rear tire is the one that changes the most while being ridden.







Science

For the little scientist inside you might remember the Gay Lussacgas law. If not here is a refresher



We have four observations to test this out on:

Front wheel 1.9 bar @ 32 C and 2.0 bar @ 33 C

Rear wheel 2.0 bar @ 33 C 2.2 bar @ 40 C

The law says P / T = k which means (1.9 + 1) / (273.15 + 32) = 0.0095 for the front tire at start.

0.0095 x (273.15 + 33) - 1 = 1.91 so not quite 2.0 so possibly we could just jumped from 1.94 to 1.96

Lets try the rear wheel

(2.0 + 1) / (273.15 + 33) = 0.0098 which will give our prediction

0.0098 x (273.15 + 40) - 1 = 2.07 so not quite the 0.2 jump as expected but roughly in the right range 




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