Drilling my shoes for Speedplay

So ive converted over to speedplay zero from my old look keo and I love them. Only prob is that I would like to get rid of that adapter plate and loose some weight and stack height. My plan is to drill 4 new holes and cut a couple of spd threaded shoe inserts in half and use those to anchor the bolts. Suggestions or experiences doing this? Background on me, Cat 1 roadie and mechanic. Shoes are Pearl Izumi Octane SL 3 hole (for now)

If the shoes aren't designed to hold 4 holes then drilling and mount may destroy your shoes or detract from its comfort.

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Morphed Bianchi Camaleonte IV 2006, Ridley Damocles 2006, Garmin, Mac

Im well aware of the risks. Comfort isnt an issue as I already have a rigid ortho inside the shoe so any small lump wont be detected. Just looking for any pointers.

You CAN redrill the soles of some shoes to accept a different cleat type OR to allow a significantly different placement.

Before DETTO PIETRO (was there an earlier shoemaker?) came out with their nylon soled shoes, the soles were leather and did not have preset mounting holes.

Several years ago, I was dissatisfied with the cleat location and decided that a well worn pair of Shimano road shoes which I have were the perfect candidate (guinea pig!?!) for attempting to re-mount the cleats in a different location.

FIRST, without a cleat on the bottom of the shoe, apply some masking tape ... either get on your trainer OR ride around-the-block OR balance on your bike in a narrow hallway & pedal for a minute/moment so that you make an impression of the pedal on the bottom of the shoe -- this is so you can 'properly' locate the holes for the cleat.

I selected the drill bit that was slightly smaller in diameter than the standard cleat mounting bolt (whatever THAT is ... I just did it visually) ... that is, you want the drill bit to match the shaft of the bolt underlying the bolt's threads.

Lay the cleat over the bottom of the shoe, mark where you want the holes ...

Remove the shoe liner ...

Drill the holes.

Now, you can either drill all the way through the sole & inner sole OR you can put a piece of tape on the bit about a half inch (?) away from the tip so you can see when-and-where to stop plunging the drill into the sole of the shoe. I don't think it matters.

You can EITHER tap the threads OR (easier) use some relatively "fat" (the helical will be slightly larger than the hole & the diameter of the shaft should be only slightly smaller) & short wood screws -- LOOK type cleats need a slightly longer screw than you will probably need ... Shimano soles are thicker than some other shoes (well, SIDI are thin by comparison) ... without looking, I think a 1/2" long screw is what I ended up after trying a slightly shorter (3/8") screw. If the screw tip protrudes into the shoe (!) then remove it and file the tip off. Basically, you can look at the length of the mounting bolts that came with the cleats & choose your wood screw accordingly.

After tapping a couple of holes, I decided to use WOOD screws. Wood screws come with 'dome' top & the type that are flush mount ... either type of screw head works, the dome top looks better. I suppose that with the Speedplay cleat that you could use a hex headed screw.

The ONLY (?) disadvantage to using wood screws is that you'll need to add a medium sized screwdriver to your toolkit -- "stubby" versions are available.

A small advantage of redrilling AND using wood screws is that the screw will never be rusted into the non-existent receiving boss the way a bolt can be.

Supposedly, Carbon Fiber cannot be taped ... I don't know if that is true. If it is true AND if you have CF soled shoes, then drill the hole incrementally larger than the bolt's diameter and then dress the hole with some JB WELD ... then, tap the JB WELD lined hole. Again, I would opt for using wood screws.

I Never would have thought to jb weld then tap the weld, awesome idea, thanks!