Need help with Rollers& jet size.

Hello all,
I've recently completed my setup on Yamaha aerox 50cc containing :
70cc Malossi sport Kit
Stage 6 replica derestricted exhaust
Geforce 3 reed valve
17.5 PHVA Delorto carb
Multivar 2000 with x3 4.5g and x3 5g rollers
110mm clutch with blue spring and red central spring
Main jet 98
Snorkel from the airbox removed + stage6 filter.
Needle 1 position below the middle(a.k.a more richer).
The scooter pulls a lot slower than the youtube videos I watched of people using the same cylinder kit. I know every scooter is specific, but can you give me directions on what to do to improve it since appreanly I'm doing something wrong?