probably cut out to save weightpurpose of the other larger hole
The larger hole on the S40 bottom bracket housing is likely for a chain guide or a similar accessory mount. It provides a spot for extra components that could help with chain management or other frame accessories.On the S40 bottom bracket housing there is a mounting (?) bracket / flange with 2 holes in it.
I’ve seen that the smaller hole can be used for a light mount stub, what is the purpose of the other larger hole?
The larger hole is usually for internal cable routing or a wiring pass-through, depending on the setup. Some people also use it for custom mounts.On the S40 bottom bracket housing there is a mounting (?) bracket / flange with 2 holes in it.
I’ve seen that the smaller hole can be used for a light mount stub, what is the purpose of the other larger hole?
YepThe larger hole is usually for internal cable routing or a wiring pass-through, depending on the setup. Some people also use it for custom mounts.