Here we go,
Well a lot of you may know this info, thats fine, this is a guide to help those who dont know!
I am a Masterfit boot fitter for an Intrawest resort, so i did all this work my self.
For best results go to your local ski shop boot guy, they will have the right tools for the job
Sometimes you have to pay and pray, aka order a boot online for a ridiculous deal, such as on backcountry or tramdock.
Ill be using my Salomon Ghost boots, which ended up being two stiff and two big.
I got my flex from 130 to about 90-100, and made it the best fitting boot i have ever owned.
I was getting a lot of shin bang and needed to soften up the boot. You need to be able to flex your boot, especially if you are doing park. To fix this problem you can start by taking off the backbone (if your boot has one) on the back of the cuff.
To counter this, and make your boot stiffer, you can install a backbone or ad a bolt in your backbone as seen in the image
The next step in softening up your boot, is cutting the clog. In most boots there is a dotted line on your clog (the lower half of your boot). I used a dremel tool to cut and shave along this dotted line. This will allow your cuff to flex forward more. ***Now this is permanent so make sure you take your boot to a shop or be damn sure you know what you want.***
Start by doing one step at a time, there are sometimes two lines. Cut one line first, try your boot out, and if you want it softer, cut the "U" shaped line, as seen in this image:
So thats how to soften up a stiff boot.
If your boot is too big, or there is too much volume,
you can fix this by getting a better insole with proper arch support and a heel lift.
A heel lift is a little wedge that goes under your insole, and will help fill up the volume making your boot SOMETIMES feel up to a half a mondo size smaller, Ex 26.5 down to 26.0
Hope this helps,
Any questions hit me up.
REMEMBER, GO TO YOUR LOCAL SHOP FOR BEST RESULTS IN MODIFYING YOUR BOOT!