I bought this Motovox Gas Mini Bike for my ten and twelve year old sons for Christmas this year and they absolutely love it! This bike is so much fun. It is surprisingly powerful and really moves for such a little bike. My sons have no problem starting it up and taking off all on their own. I use regular 87 octane gasoline and have had no problems mechanically with it. My boys have ridden it on city street, up and down hills in the suburbs and through huge, bumpy hills out in the country and handled all of them with no problems. I was initially concerned with them wrecking or getting hurt. But they surprised me when they quickly learned how to operate it without crashing. I still try to keep an eye on them though because boys will be boys! It comes with a 90 day warranty. It goes up to 23 miles an hour, which is just enough speed to keep my boys entertained for hours! I highly recommend this to anyone looking for a good bike for their kids.