The average weight of a BMX is between twenty-three and twenty-six pounds, which is enough for most (new) riders. BMX bikes, on the other hand, are intended to be used off-road. The weight isn't as vital as the quality of the BMX bike parts. For example, if the forks are made out of plastic, even though they may look like they would handle the load better than steel forks, then they won't last as long and could cause you problems later. A heavy rider on a light bike will put more stress on the wheels and brakes. If these things aren't up to the job, you may need new parts. As for the frame, if it's not built well, it may get damaged over time. Even though BMX bikes tend to be cheaper than other bicycles, this does not mean that they're not worth spending money on. You should buy high-quality parts at any price. As for the size of the rider, most BMX bikes are designed to fit people who are about 5'8" tall. However, some companies make smaller or larger models so check with your local shop before you buy anything. Finally, don't be afraid to ask questions. There are many people out there who know more about bikes than others, so take advantage of them.