Personally I think honda stock reeds are one of the worst components on the bikes.
I think honda in its effort to make a bike that ran forever, made reeds that worked but not well. They were too concerned with the reeds no breaking and getting sucked into the engine, and neglect to make them seal really well. Its just my personal theory.
If you notice all the old honda expresses you see have these little white plastic boxes over their airfilter. These boxes all have nasty brown stains where gas has been puked past the reeds and has begun rotting the plastic.