Well, the first thing I did was get the Boyeson reed and jetted it. Later I added stiffer clutch springs to get it out of the corners and off the gate quicker, and a no-toil filter. The lower gear helped a lot of others, but I never bothered with them. If you are still using the stock pegs, get rid of them, kids are a bit more comfortable if their feet don't slide around. I think I spent less than $100 on mods to the bike and watched my boy get enough air to pull no-footers. If you are AMA illegal anyway, FMF makes a Fatty and a couple of silencers for it, I never used them either.