It is driving me crazy that more people aren't using the free (or inexpensive) mods that are available to kdx owners. It seems most are tossing the airbox lid and rejetting. beyond that it seems lots of people are missing out. they go for the pipes, silencers, reed cages, both sprockets and a chain, professional suspension work,etc. before they try the free stuff to see if it works for them. My favorite mod would be my pipe and fork springs and then my Vforce3. But large improvements (to me) for less than $20 are counter shaft sprocket change (gearing), air snorkel removed from lid (I chose to leave my lid on), jetting which should be done with almost any engine mod, timing change ($10-$15 tool purchase), and my favorite free mod right next to changing my timing was removing the 2 shims in the forks. Then there almost countless little things to be done to make the bike fit your personal needs and use. Maybe I'm just a tight wad though!