Two days ago I was on my 2020 Vespa GTS 300 HPE Touring riding on California Highway 580 eastbound when the throttle got stuck completely open. Because it was night time I did not want to lose my lights (and for other reasons) I used the kill switch once I was on the shoulder. I called AAA and had it towed to my mother's house where I am able to work on it. In the morning I inspected the throttle cable and it's components and noticed many of them were quite dirty (I just made it passed 30,000) and after carefully cleaning and lubricating the throttle cable at various points it no longer stuck.
Once the throttle cable issue was resolved I started the maintenance that I had originally planned to do, change the belt, rollers and oil. While changing the rollers I noticed that several of them where in terrible shape, in fact the worst I had ever seen. I have attached a picture of them for your viewing pleasure. I was wondering if using the kill switch caused this serious damage to the rollers and does using the kill switch damage the engine?
The reason I ask is that after doing the maintenance I took my Vespa for a test drive and discovered that it would not go faster then 42 mph and I had my check engine light on. After breaking out my code reader I learned that it was the O2 sensor that was producing the error code. I was wondering if a bad O2 sensor would cause the dramatic reduction in speed and did using the kill switch cause the problem.
This is only the second issue I have ever had with my GTS 300 the first issue was the Immobilizer antenna going bad and that was a real simple fix. Hopefully this will be the same.