I’ve resisted the idea of doing this mod for awhile but am finding myself increasingly more eager to shave weight and especially do it by making my own parts.  This mod is quite extreme in the eyes of many.  It involves switching the stainless steel butterflies of the pedals to aluminum pieces.  Aluminum is obviously lighter but it comes at the price of being considerably weaker too. The job of these bowties is mainly to resist the upward pulling force of your legs.  Personally I think that Titanium would be a better material for this application but I don’t have access to it and it doesn’t save as much weight.

The stock steel pieces come in a around 8.9 grams each.  There are 4 of them used per pair of pedals.
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Projected weight for aluminum 6061 pieces are 2.9 grams each.  That’s a savings of over 20 grams for the whole setup and its rotational mass too so that’ll be quite advantageous.  Aluminum should wear a lot faster but these are quite easy to make so I can replace them as needed.
Speedplay Butterfly