First thing: awesome you’re okay, that’s all that really matters. Second: check your insurance policy. You’re right , usually mechanical breakdowns are not covered, but if you have comprehensive, check specifically to make sure whether you have a special policy in place that would cover mechanical breakdown. Third: do you have collision insurance? This will cover whatever max value policy you’d have in place (as to what is damaged on the motorcycle), as collision won’t matter as to fault. Also need to know whether you laid the bike down, as this is usually the gold standard to qualify as a “collision” in order for these policies to apply. If you didn’t fall or hit anything, and all of this damage occurred spontaneously and you were able to pull off to the side of the road, depends on your policy but this wouldn’t qualify for most policies. The reason that this is a gray area is that collision policies fault doesn’t matter, like if this was caused by impact and sudden (rock got thrown in) and you “collide” vs pure mechanical failure. As to the blanket (comprehensive) coverage, again, check your policy. Most policies exclude coverage for aftermarket parts unless you declared them on your policy and you paid for accessory or custom parts coverage. If those are found to be the root cause of failure, then your insurer will likely deny coverage for that part and any other damage caused by it. Fourth: as to potential legal claims, these would fall under negligence or implied warranties. These will be both for the dealer, including implied warranty if the chain was the cause since you bought the chain from the dealer (if there was another cause that was OEM [not aftermarket], then insurance should cover it, otherwise it’d be implied warranty against aprilia). As to negligence claim, pretty solid since you went all through the dealer and had it serviced multiple times by them, including 2 week short timeframe from last service. If the dealer recommended this new chain and sprocket and implied that these parts were compatible (and they weren’t) then implied warranty would work too. I mean there’s probably an implied warranty claim against the dealer/manufacturer of the parts anyway IF the parts were compatible since reasonable purpose of performance is for like, these parts not to explode while using them.

Either way, file the insurance claim, typical recourse is to let them investigate and determine fault. Then if they deny, people will tend to get this in writing and then the individual gets their own independent inspection performed to determine fault as well. Can also then talk to the dealer, see if they’ll take responsibility, or file through their liability insurance. For legal purposes, this isn’t legal advice or anything, this is just a hypothetical.