The reeds are made of different materials to flex at different frequencies.
The stiffer reeds usually are sold for top end as they have less tendancy to bounceoff the reed block and "Flutter".
The same type of thing that happenst to standard type valves when they Float.
The reeds alone may make a small improvement for the range they are designed to work in.
If you have a stock bike you may see a small improvement, but again its where the reed is designed to work.
as an example, alot of guys don't like the boyesen reeds and block for their 500's. They are a dual stage reed with a soft inner reed and a stiffer reed on the 2nd stageor outside the soft reed. The boyesen also has about 3/4 the area of a v-force that helps keep the velocity of the air fuel mixture high to aid in filling the cylinder at low engine speeds.
The soft inner reed has good throttle response and is great for bottom end riding ( tight single track)
I use them and work great for me. Guys who ride the desert or dunes probably won't or don't like the setup as it lacks the top end they spend alot of their riding time in.
They most often use a V-force set up. large stiff carbon reeds will maintain their shape and continue to operate at a rev range my boyesen would be fluttering (or Bouncing off the reed block) .
I'm sorry I don't know how else I can help.
Let us know what you decided to do and how its working out.
Take Care,
Tuck\o/
Vforce is actually pretty soft... just doesnt flutter due to not having to open as far because of surface area...
The main question to ask you isnt what reeds do for performance..
its what they do for LACK OF performance..
If your reeds in your bike are more than 2 season's old.. (My kind of season). Replace them.. they are worn out...
Reeds are a Tuning Item, and a WEAR ITEM... like chain and sprockets...
Yes the Vforce will give better crisp'er throttle over the stock cage... But if your not a Good Tuner.... your wastin your money, as you will see better HP etc gains from JETTING THE BIKE CORRECTLY.... soooooo many people ask me.. "what pipe, what reeds, what $$$$ can I spend" Yet they wont spend the time to get the jetting correct, and find the 10HP they are already down on... but are spending $100's of dollars to find 2-3HP...