Indoor Bike Improvement #3 - On/Off switch & Wireless Charger

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3 of 10 - On/Off Switch 

3 years ago, the SB20 firmware was rapidly evolving - with lots of bugs. We were all beta testers in 2020.  Powering the bike off and then on was commonplace.  

One of the first modifications I made was an on/off switch.  


I put my switch on the bike-side of the SB20 power brick. This means power is interrupted immediately when the switch is turned off. 



The situation is a little different with a remote or physical switch at a wall receptacle. These switches work fine but you must wait several seconds when powering off. The SB20 power brick must drain sufficiently for the SB20 to reset. 



Good Digital Hygiene in 2023

I remain a fan of powering on my indoor bike before each riding session. This includes restarting all of the apps I use. With no error display or indicator lights, it is impossible to tell if the SB20 is healthy. Not what I want to worry about before a big event.

Version 1


The first version was a plastic tab with a push button switch that screwed into the phone tray. Like all future versions, a light on the push button confirms the bike is getting power. 

... but something was missing ...

Version 2 with Phone Charging


I always thought wireless charging was a natural for the SB20 phone tray. Version 2 had an integrated on/off switch and wireless charge pad. The result was bigger than I wanted. It also used the built-in USB power supply that appeared to be under-sized for this task.

Version 3


I constructed the 3rd (and currently final) version with a 3mm thick aluminum plate that I polished and reshaped to fit the SB20 phone tray. Sidebars keep the phone in place during hard sprints. It also uses my 120W external power supply / charger.

* * * * * *

Epilog: It Takes too Long

Many people say it takes too long to restart everything before each ride. 

Video: With a good on/off switch, these claims may be exaggerated 😁.  




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