Can cycle shoes be widened?
According to this manufacturer's web site, some shoes can be &quot;heat-molded&quot;:

Heat Molding
This cycling shoe is the most heat moldable shoe on the market today. Bont's resin is developed in house and has been perfected over 36 years to be an extremely stiff resin that becomes pliable at relatively low temperatures. The base of the shoe is moldable which means all stiff areas of the shoe can be molded in a standard oven. You do not need to mold your shoes if they fit you straight out of the box. To mold your shoes, remove any cleats, laces or cleat mounting screws and innersole before molding. Failure to remove the innersole can result in it becoming deformed by the heat. Pre heat the oven to 70°C/160°F. Place the shoe in the oven for 20 minutes. Higher temperatures will void your warranty and may damage your boot. Caution: Do not place your feet in the hot shoes or you may burn your feet. Let them cool a little and test the shoe temperature with your hand before placing your feet in the shoes. Tighten the straps and allow to cool. If you have any lumps or bunions on your feet or if there are any areas causing discomfort, while the shoe is hot you can use the round end of a screwdriver to press out any part of the boot. You can heat mold the shoes as many times as you like.

I read some people recommend a hair-dryer, but this suggestion of an oven seems to me more measured, a more accurate temperature.