Done

Edited November 24, 20223 yr by ridgrunr
Through with TC

They might be air vent holes they put in before welding, when a part is welded like the hollow section of the swing arm is welded to the alloy bearing part you mentioned the air inside will heat up and increase in pressure and would want to escape leading to a defected joint, so a small hole is put into part of the fabrication to allow the hot air from the hollow section to escape via the small hole in the bearing part

If you look round your Beta alloy frame and swing arm you will see various small vent holes to release the inside air pressure when welded