I'm thinking about going with a Schwinn Landmark for my first build now actually, with a 70cc engine from thatsdax. If I were to use this bike, what would I have to upgrade on it to make it make it more durable, or rather, safe? New tires, innertubes, or rims? A better chain that won't break? What parts have a tendency to fail on these types of bikes, anyway? If you have any suggestions, post some links please.