There's no need to tell them about shocks or fork upgrades, you can't ride the bike without either of them they aren't additions. They don't enhance performance, albeit, you be able to ride slightly faster over any given stretch of road, but power isn't increased.Even additions that don't enhance power like legle end cans (providing they cost no more the a standard system) most companies aren't interested. Things like screens, heated grips, tail tidy, luggage systems, rearsets, air filter changes, huggers, steering damper, crash bungs/bars, brake hoses.
This years insurance renewal included a list of 29 modifications that the insurer did not want to know about. Strangely suspension mods weren't on the list, when in the majority of cases, moneys been spent improving the stock suspension, making it easier and safer to ride. Therefore less likely to be involved in a claim, so the insurers should be paying us, via discounts, for improving the bikes they are insuring.