DONT put the gearing back to stock!!
I'm saying move it away from stock... gearing it up a bit to a higher ratio (type-o above)... run 19/42 or 19/43 gearing...
I'd say you should run a 120/340 spring in the primary with 10/68-70 weights... MAKE SURE That the primary is shimmed properly and run the 3211115 belt only, IMO. This should give you a less harsh engagement and smoother clutch engagement.
All this is assuming that you have a helix in the secondary that is approx 66-42 and a stock or red/pink secondary spring.
Also, add an Isovibe handlebar mount from Grip-N-Rip to cut down on the vibrations from the motor and make her a happier rider.
If it is for your wife, run the SPG Ultra Q can... nice and quiet light and compact as well. Most of the others are pretty loud.