Pre 16 redesign, the rocker arm barings fail. Best case you replace with no damage but that's unlikely, next best case is as per Taipan's and you need to replace the valve train at about £800. Worse case the rollers fall out of the bearing into the rest of the engineLe_Fromage_Grande wrote: ↑Mon Oct 04, 2021 4:06 pm I assume the rocker arms wear and you lose valve lift and get a rattly engine if they get worn?
Mines a late 2015 bought in 2016 so the old design. Forums say 2014 on 690s have a redesigned rocker arm baring which doesn't fail. Mine had that redesigned part and Jim Aim said it'd be fine. But when they checked it they said it felt like the exhaust bearing was on it's way out. So in my experience it looks like pre 2016 models (different engine) need the rocker arm bearings checked/replaced at least every 12k miles probably more like 6k. Some people have done 30k miles without touching the rocker arms, other have gone big time with sub 8k miles. That 690 Enduro with 84k on it was killed by the bearings failing, but up to that point they were never touched.
KTM specify a 6k mile valve check. Chatting to 2 different KTM mechanic's I think this is more to do with checking the bearing than the valves needing adjusting. Checking the bearing is part of the service. Some owners check them annually and if you are spanner competent it only takes an hour and a quarter or so.
Replacing mine cost £560 all in with the 12k mile service. So not massive cost but not great considering there's no guarantee they'll last any better than the last set.
As for engine rattles 690s are very loud rattly engines by design. I always put my ear plugs in first as else it scares me and that was from new
Other than that the engines are good. It is a big BUT though as I said.
2016s on have a different head design and a twin balancers and apparently don't have the issue.
your thread made me think "i'd love another 690" when i was sitting there on Sunday .... 45 mins later, i was browsing... the rest... well, that's fairly apparent.