The 150cc that come on the spider box, are pretty easy to work on. (Youtube) there are plenty here that can help you with a bigger engine bore kit.
If you haven't replaced yet. The axle will break one day.
The diamond plated fenders are nice. But the mounting for the fronts are less then perfect. You might need to fab up something different.
They are fun to work on. Keeps me busy most of the year.
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