flimsy illegal scooter

I have 2 jackshafts that'll allow me to run a 2spd auto. Should i go with a low gear and a high gear or stay single speed. Low gear 9.5:1 for 22.5"tires ~ 11.4:1 for 27" tires High gear 6.69:1 for 22.5"tires ~ 8.06:1 for 27" tires ~4100rpm is where the second clutch kicks in for high...