buildyourown

If your shims are cupped you should replace the rocker. It will wear the new shims at an accelerated rate. Check your rocker shafts and cam too.
Im fixing the same issue. My motor was ran with clogged screens and the rockers were starved for oil. Check your exhaust side too even if the clearance is in spec. My shaft had bound but the clearance was correct.

Whosaberg

Blue Marble Rider Youtube Channel has a complete video for 09-on FE bikes. Very good.

mdc

Firstly thanks to jeffk95z for sending me the collated instructions and photos from this Thread very easy to follow except I have a question regarding the rocker Arm shaft.

I used the rocker arm shaft method and pulled it out completely ( Yes I know the instructions in the thread say do not completely remove the shaft but I missed that bit )

Is there anyway to tell which way the rocker arm was in the there originally , maybe some wear marks etc....? I get in can on only go 2 ways so 50% chance it goes in the same way


Valve check specs

2010 450FE with 6600km 180 hours

Inlet Valves both within spec

Exhaust right side within Spec

Exhaust left 0.10mm fit and 0.12mm did not fit also tried and 0.11mm which did not fit - out of spec

The Shim I removed for left Exhaust measured 2.81mm ( it actually has 2.x5 stamped on it. the number after the . is worn off )

So off to the KTM store for a 2.60 shim or there about

cheers
Marc