Razor MX500 dirt rocket with a +5 speed booster kit added on all three. My Etsy and Ebay links of the kit in my comments.

Razor MX500 with a Mykwilwin +5 speed booster turbo kit added on all three.
Etsy, https://www.etsy.com/listing/85934449/speed-booster-kit-for-razor-mx500-mx650?ref=listing_published_alert Ebay, https://www.ebay.com/itm/165543118071 Amazon, https://www.amazon.com/dp/B0CRH4BRDV/ref=sr_1_1?crid=8KFIWGT4SNVD&keywords=razor+%2B5+speed+booster&qid=1704393034&s=books&sprefix=razor+%2B5+speed+booster%2Cstripbooks%2C113&sr=1-1 How to install, https://www.youtube.com/watch?v=_zGzVXq6vps And racing batteries and a charger, https://www.ebay.com/itm/256369185637?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=ygD1HAaZRGK&sssrc=4429486&ssuid=ygD1HAaZRGK&var=&widget_ver=artemis&media=COPY How to install video on Youtube, https://www.youtube.com/watch?v=_zGzVXq6vps