WARNING, January 2013: For removing torx/star drive ski binding screws, use a high quality and impact driver rated torx bit rotated by hand, possibly with the help of a wrench cheater, with extra care to prevent breaking the bit off in the screw. Pre-heat stuborn screws with a good quality and hot soldering iron. I’ve been having a lot of trouble torx bits breaking during screw removal.
Ski shops already know this, but here is the info for any readers upgrading to new Dynafit Radical FT or ST bindings with non-removable brakes and doing home mounting. When inserting the rear screws you’ll need a longer star drive T-20 driver with a narrow shaft, otherwise known as a hexalobular internal driving feature tool. Yeah, I was reading the Wiki.
A regular type hand T-20 star drive screwdriver will work fine, but if you’re using insert bits with a power driver or bit holder screwdriver you’ll need 2-inch (or longer) insert bits rather than the little shorties. As shown, the longer bit fits nicely between the brake parts. If you use a shorter insert bit the holder shaft doesn’t get enough clearance. In a pinch, you can grind clearance notches in the plastic brake plate, but if you use insert bits it’s better to just buy a few 2-inch T-20 drivers. I got mine at Lowe’s, and they’re easy to find on Amazon and elsewhere online. Buy a few for friends and for your repair kit.
If you want an even more elegant solution you can get longer Torx bits, but we’ve found the 2 inch to be fine. See Amazon links below for some shopping options. Stocking stuffers for the ski mech in your life?