The cam failures seem down to incorrect hardening on the cam lobes, as it seems to be pretty inconsistent which lobe fails. The cam lobes are pressed on, so it's possible a bad batch of cam lobes can get distributed across many bikes, and depending on the production processes it wouldn't be trivial to identify which bikes would have gotten the bad batch, especially if the hardening is borderline, so it's not easy to detect failure.
I'm not surprised people are seeing repeated failures - from the parts lists I've seen from cam failures, it seems like dealership are either replacing the cams and followers, occasionally they do the head, but I don't think after you've dumped a good chunk of metal into the motor you can trust that motor will do the distance anymore - I'd want to pull / spec the oil pump, at the very least, and I think that's a pretty invasive job on the LC8c. I'd want a complete replacement engine if I did have a cam failure, and it doesn't seem like most dealerships or owners are pushing for that.
KTM has also sold a
lot of bikes (280k KTMs, 68k Huskys) in 2024, so even if this is a 1/1000 failure, and the LC8c platforms are only 10% of what they sell, that'd still be 30 bikes a year. After 7 years of approximately those numbers, you'd have a number of very disgruntled customers. If it's a 1/100 failure, you'd see ~300 a year, ~1500 after the 7 years that the LC8c has been in service (assuming some wiggle room for selling fewer bikes at the start). I think the numbers are probably closer to 1/1000 than they are 1/100, considering my local KTM dealership has never seen a cam failure, despite moving a lot of 790/890s and being in business since long before the LC8c was released.
The only attempt to collect data I've seen about this is here:
https://advrider.com/f/threads/cam-lobe-wear-poll.1698291/
If advrider can only muster up about 40 people who have ever
seen the problem in person, with a couple of people reporting in the thread they had the issue themselves - it can't be that widespread given the total # of bikes sold. People treat KTM like they're still a tiny manufacturer, but they sell more bikes than Yamaha in the US! (Source:
https://www.motorcycle.com/features/interview-with-ktms-stefan-pierer-part-2.html )
I also think there is a confounding factor here in that if your valves get to zero clearance, you're going to beat the hell out of your cams anyways, so I have a feeling that much like Yamaha R6s, where they stretched the hell out of the maintenance intervals and the bikes ended up burning valves due to zero clearance, the clearances aren't always set loose enough from the factory, and it's good to check them sooner than the initial 18k spec, especially if you ride offroad and can ingest dust.
