Just FYI, the noise and damage cause when you tried to start the engine that is already started, is honestly one of those ratio's of luck... 90 times out of 100 nothing happens, 5 times a tooth on either the kicker gear or the idler gets a nick in it, from your own description my bet is that the idler gear, got nicked, because it turns all the time with clutch basket.

Ok now where my luck kicks in (except if I enter the lottery) I had the circlip come off the kickstart shaft, on a brand NEW raga. It managed to flick itself into the teeth in the clutch basket, it then stuck there and went round and and round through the crank gear and the idler gear, it made a racket, we shut it off instantly, and still went through several tries at "parts swapping" until we even reluctantly even considered the clutch basket, and swapped it. and actually bent the clutch basket enough, that once we changed the clutch basket, the noise went away finally.

had the same noise from my 2002 280 pro i bought as a non runner for a lot of years, so decided to change the main bearings and seals but when rebuild and started it sounded like a bag of bolts and my heart sank but after i strip the clutch side off notice under close inspetion that the basket and crank gear had marks on them as something must of came loose at one time and causing the damage,got the dremel out and clean the damage up on the gear wheels the best i could and rebuild and started,this cut the noise down by half but now i know what to replace when i get the ££££££ in