re: 'YOU CAN NOT ADJUST YOUR JETTING BY CHANGING THE FUEL:OIL RATIO'
Yes, you can, yes, you do.
If the point is to change the air/fuel ratio, that isn't the way you do it, but it does have that effect. 40:1 premix is more rich air/fuel-wise than is 32:1. There are more gasoline parts per oil part..more gas is more rich.
What whatever expert told you, '32:1 is way too rich and I should run 40:1 after breakin' is wrong. It's backwards. Don't use the terms rich/lean when referring to premix ratios unless it is very clear by everyone what the subject is.
Please DO listen to the 'experts'. The problem is determining who is and who is not an expert...and whether the definition of expert is: ex=has-been, spurt=drip under pressure.
Here's an expert you can count on. Check out the 'Every kdx rider should read...' stickied to the top of this forum. Go do CDave's site. Read the new bike prep section. DO IT!! Read the information on basic jetting setups. DO IT!!
If you're paranoid (or just safe) you will want to get rid of the oem piston on the 220. No....it does NOT only break on modified bikes. It breaks on bone stock bikes, too. Not as often, true. But it does indeed break.
One thing I don't think is on CDave's site that you may want to consider. It will save you a lot of heartache in the future if you 'grease' the spoke/nipple sets. Yeah..it's a pain, but it beats never getting them off again in the future. You need to take the tire off, unscrew each nip, coat the spoke threads with an anti/never-seize compound. Torque them back together, or at the very least tighten them to the same 'tink' as the other spokes.
Yes, I realize this isn't generally considered a 'have to' do it deal. I also know it will be a big favor done for yourself in the future.
After the first ride, check the spokes anyway. You don't have to have a spoke torque tool (only about $150). You can accomplish that with the 'tink' method. Keep in mind the correct torque (look it up to confirm) is only something like 18in/lb.
Oh...put some anti-sieze on your brake pad pins, too. Do that with your other new-bike prep.