So at 145 hours I figured it was finally time to check the valve clearance on my 2017 FC350. Turns out they're all on the loose side, so I pulled the cams only to discover that all four shims are 2.6 mm thick. My Hot Cams kit only goes up to 2.6, and looking up the OEM shim sizes shows the same max size of 2.6 mm. Am I missing something, is there a thicker 8.9 mm diameter kit available?
Back info- I've owned the bike since 10.6 hours, and it came equipped with porting by Dan Crower, along with his cam (thought it was both cams, but only the intake has DCR imprinted on it. Exhaust appears stock). It's never been a fantastic starting bike, but lately it likes to backfire every now and then when the magic button is first pressed. It always starts, doesn't have any more valve train noise than any other Austrian steed, and it runs like a Gazelle with it's ass on fire.
I’d be checking for wear on surfaces like the ends of the valves, the buckets, and the cams. However, the fact that they were all at max shim thickness seems to me to either mean there was a tolerance issue at the factory (cam bores too high?) or that the builder set it up to hedge it against seat wear (not sure if any builders do that?), or that the builder milled the ends of the stock valves to clean them up.
It's possible that the cam is a regrind and has a reduced base circle. DCR does sell custom/thicker shims for KTMs too.https://danielcrowerracing.com/i-23901349-ktm-husq-valve-shims-8-90mm-outside-diameter-shims-for-ktm-husqvarna.html
I talked to Dan today, and my exhaust side at .012 and .013 need to be shimmed, but my intake at .007 and .008 are fine. Shims are ordered and I should be good to go.
Hindsight I should have checked my valves when I first bought the bike as a reference point, but it ran great and I never thought there would be a need for thicker than normal shims.
Good call, didn’t think about that mod.
Post a reply to: Thicker KTM shims?