14g is pretty common for a GY6 150 stock... but it varies from scoot to scoot. Every GY6 150 doesn't use the same weights and I'm not sure about your specific model. If you still have them, weigh them on a small scale. Some folks that didn't want to buy a little scale have said they weighed them at a post office or shipping store.
Brent My two-stroke doesn't burn much oil. Most of the smoke that trails behind is actually the crushed and incinerated hopes and dreams of four-stroke enthusiasts.