Hi guys. I'm getting ready to do a complete fatty build on a 2019 ruckus. I already have my mind set on stretching it and putting 2 piece wheels on it. My only question is do I really want to ditch the reliable honda 49cc for a 150cc gy6? Or should should I bore out the stock motor? All opinions are welcome and appreciated. Thanks in advanced!

 

If you're looking for speed, go with the swap. Doing a GY6 engine swap is NOT for the non-mechanically inclined. A lot of the cheap parts(carb, exhaust manifold, stator,) will have to be replaced with quality items. The main reason for swapping is low down torque and higher top speeds.
If you are happy with the 49cc GET motor then stick with it, it's capable of 50mph with the right parts and tuning. Boring it out will make it less reliable. I personally have both and I love them equally but the GY6 is just miles faster.
There are other options to the GY6 swap. Honda PCX 125cc-150cc engine, Honda Elite 150cc-250cc engine, Honda Reflex 250cc engine or Yamaha Zuma 125cc engine. All of the Honda options are expensive and require custom fabrication.
The Yamaha swap is on par with the GY6 in terms of readily available swap kits.
Since yours is brand new, I'd keep it 49cc and just tune the hell out of it. (Polini variator kit, quality exhaust, aftermarket air filter and NCY cdi)
2014 Ruckus with GY6 swap and 12x8 fatty.

2014 Ruckus with stock motor and skinny stretch kit.

 

Thanks for all the info man! I'm probably just going to ride the ruckus with the stock motor just to see how I like it and then further down the road do the gy6 swap. I'm mostly just worried about fuel consumption (due to the 1.3 gallons the tank holds) and reliability with the gy6.