My tinnitus was most likely caused by a 3rd degree concussion from snowboarding (younger dumber days). However, I would count concerts, cut saws, motorcycling, and especially stress as contributing factors. I definitely notice that my tinnitus is louder, and has added frequencies/tones, after long rides in really windy conditions. It does calm down to its normal jet engine volume after a day or two.
Interestingly, a few years back I found a book called 'Silencing the Storm' written by a retired medical researcher who developed tinnitus later in life and spent years working on a fix for his tinnitus. The cause of his tinnitus (as there are 1,000+ causes) that he concluded was years of pissing off the occipital nerve bundles in the neck from being stressed out (in simplified terms). He was able to fix his through over a year of neck strengthening and relaxations. Sadly I just lost the book in a flood and I can't find it on Google.
Anyways, I do see motorcycling being a cause of tinnitus in the form of the loud noise and added stress on the neck. However, for me, motorcycling is also the solution to my stress (insert Homer Simpson quote here). It's a cruel irony, but to help I spend the extra money for a lighter, more aerodynamic helmet as it is worth every penny. Now I am working on the windscreen and wind turbulence.
Any tinnitus sufferer has my deepest sympathies. Ten years of torture and I'm only 30, I hope somebody comes up with some better happy pills for it.
For every mile of road there are two miles of ditches.