I had a 250 Nighthawk and it didn't seem to have near 25 HP. If I remember right it's a 230CC twin. Just got back from some shopping at Harbor Freight and picked up some 10" o-ring pliers for the next time I change the sprocket ($11. with 20% off coupon that I carry in my wallet) and I think the 13/33 ratio is going to be fine. It pulls fine for my 210 lbs. Maybe you should try 13/35?
Gathered a small crowd in the parking lot as usual. People like the bike.
Gotta do something about some luggage/saddle bags,rack or whatever.