Yes a BBK is the best way to get more power . I would get an impact driver to remove the variator and weigh the roller weights you have . My 4T ( 4 stroke ) came with 8 gram rollers and I replaced with 5 gram rollers and wow take off and up hill were so much better . The small scoot are already too lean so a size or two larger main jet ( 5 bucks ) will help a lot . I would go ahead and get a jet kit so you will have many sizes to pick from and keep the larger ones for if you decide to go with a BBK later . Sometimes replacing the torque ( also called contra ) spring with a stiffer one has helped some go up hill faster along with lighter rollers . Some carbs are sealed so the air/fuel screw is covered and the needle may not have a clip to adjust its position . There is more than one type so look here to see 4 types of carbs some use
http://www.partsforscooters.com/Stre...tors-and-Parts When looking for parts forget the brand and model but instead go by the engine which most GY6 50s are a 139QMB engine . Scrappydog has a 80cc crate engine assembled with the CVT in tack so you just unbolt your case and replace it . This is easier and less chance of a mistake if you rebuild the engine which is very easy to do