you say "lots of people.." , i'm saying you don't know what your talking about in regards to MOST riders using auto clutches for WOODS riding. I have 2 of em, i ride 20hrs a month with MANY racers that have them, I line up in Harescrambles with MANY racers that have them.
There is an old saying, you might be too young to have heard it.. or understand it. But it goes something like "when 1 person says your wrong.. you might not be wrong.. but when many say your wrong you might be wrong".. Where do think you stand in this discussion?
That being said.. i have it on pretty high authority (top GNCC rider but won't post his name just yet, but trust me when i say he's one bad dude..) that most PRO GNCC riders DO NOT use an auto clutch.. But, pro GNCC riders make up a pretty small % of the tight woods riders, novice riders, and riders that otherwise benefit from the auto clutch.
the reason the rpms are rising slower is because of the heavier flywheel weight. the hp is simply the out put of the engine and its ability to gain speed. in order to gain speed you have to climb in rpms. there for it is making less horse power at specific rpms. say your bike was putting out 30 hp at 8000rpms. with a fww it puts out 29hp at 8000rpms and at 8200rpms it puts out 30 hp. this is just a possible example. do any of you know how an engine works? i wish i could find a way to explain to you how this works.
as for the auto clutch. everyone i have seen run them has had problems with them. like i said maybe its the way they are setting them up but if thats the case its a design flaw. they should be made simpler to set up for those DIY weekend warriors out there