With switching wheels the weight loss is felt in a couple different ways: Overall weight On a bike that only weighs, let's say, 28 lbs (12,700g) a loss of .9 lbs (410g) is about 3% savings.
A single exposure to a sudden extremely loud noise can also cause tinnitus. A variety of other conditions and illnesses can lead to tinnitus, including: Blockages of the ear due to a buildup of wax, an ear infection, or rarely, a benign tumor of the nerve that allows us to hear (auditory nerve)
Just about anything that can cause hearing loss can also cause tinnitus. The most common causes are: Noise exposure (e.g. from shooting or machines at work), a natural part of the aging process, head injury (e.g. from a car accident or fall), as a side effect of medications (e.g. aspirin).