Intake and Exhaust Valve Adjustment, KTM 450 EXC 2003


Others have documented and reported how to adjust the valves on this four stroke enduro motorcycle engine--this is my experience and a few more pictures.

I used the method described by DJK here on KTMTalk and here as a web page. A copy of the KTM Technical Bulletin concerning the valve clearance is here.

Hardest part of this? Cleaning and re-cleaning the bike, as there is dirt tucked in every nook and cranny around the engine, and unassembling and reassembling everything that gets between me and the valves. Turning the rear wheel to the right position and adjusting the valves is itself very easy, though easier still with two people. I pulled off the spark plug wire cap and tucked the cap out of the way, but found a ton of dirt down in the spark plug recess--which I easily washed out with a little brake cleaner spray (there is a hole on the side of engine head that allows the fluid/dirt to drain out of the spark plug recess, and you can see this hole on the photos below). I pulled the crankcase breather tube off the carb intake manifold to get it out of the way also. My feeler guage is an antique--I think I used it to adjust the valves on our Honda CT-70 when I was a kid--you can see the stains on it. The guages are straight, but I bent the appropriate one about 45 degrees, and it worked OK. These pictures show adjustment of the exhaust valves (two of them), but the intake valves on the back side of the engine are identical and adjusted in a similar fashion though with a different cam position.



Copyright 2003 Rob Crockett, all rights reserved.