Its just got a metal spur gear and a couple of (cheap) chassis braces. Its going to be sold soon, I was breaking stuff faster than I could replace it. The engine I liked though, started easy and ran well (if a little slow). In the end I bought a hyper because the parts are MUCH cheaper and theres more choice available. The RG is in the hyper with the pipe. I built the new one from a kit and replaced a few bits with stronger items so it should (?) take much more punishment.