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Help finding TDC (for valve adjustment)


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2009 450 XCF

I've got the factory service manual which is the most worthless ever. I cannot find TDC, after 30 mins of turning the crank end and sticking a zip tie in the spark plug hole and looking for the mark on the cam chain gear. A few questions which may help you help me.

1. To find TDC should I be rotating the wheel forward or rearward? If I'm using the bolt on the end of the crankshaft; should I be rotating that clockwise or counterclockwise? (i'm using the end of the crankshaft method because despite being in 5th gear, I can't get the engine to turn using the rear wheel rotation method).

2. The bolt that is supposed to hold engine in TDC: how far in is it supposed to thread in once I got it at TDC? (I can get it to thread all the way in until it keeps spinning but it doesn't stop or engage anything.)

3. When I'm at TDC are the cam lobes on both cams supposed to be facing away from eachother or towards eachother?

4. As mentioned my cam chain gear has just one indented mark on it. Whenever I get it to the top, where one would assume the engine should be close to TDC; the ziptie is never at it's highest and the cam lobes are neither facing directly at eachother or directly away from eachother!

I know, I know I could be on the wrong stroke but I've turned that engine over a hundred times and I can't get anything to line up: If I get the cam chain gear mark on top, the zip tie isn't at it's peak or the lobes are facing every which way or vice versa. I'm stumped and frusterated. (Would think such a well engineered bike would have a decent manual, apparently not.)

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Its really simple...

You're on the right track with turning the crank, thats all right.

Just turn the motor until you see the valves are all closed. There is only ONE PLACE in the cycle when that happens, thats TDC. I use a long, and ultra thin, bendable screw driver and shove it in the spark plug hole. When it stops moving at the top of the cycle and the valves aren't under load, thats it!

You don't need to do any of this to check clearances. All ya need to do is tap the starter until one of the cam lobes isn't pushing on the rocker to open the valve and measure the clearance. Then do the same thing again until the other cam lobes aren't touching the rockers. It literally takes 20 seconds to check clearances using that method. I know KTM says for you to do all this extra work, but they expect the motor to be on a bench, not in your bike.

Edited by tye1138
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Its really simple...

You're on the right track with turning the crank, thats all right.

Just turn the motor until you see the valves are all closed. There is only ONE PLACE in the cycle when that happens, thats TDC. I use a long, and ultra thin, bendable screw driver and shove it in the spark plug hole. When it stops moving at the top of the cycle and the valves aren't under load, thats it!

You don't need to do any of this to check clearances. All ya need to do is tap the starter until one of the cam lobes isn't pushing on the rocker to open the valve and measure the clearance. Then do the same thing again until the other cam lobes aren't touching the rockers. It literally takes 20 seconds to check clearances using that method. I know KTM says for you to do all this extra work, but they expect the motor to be on a bench, not in your bike.

Tye you sure know your stuff! I see you posting everywhere. I wish I had your mechanical skill. Right now I am just reading everything posted here in TT and manuals that I can find.

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Anyone with a good way to find TDC on my '13 350.....with Rekluse, no kickstarter. In the past, I've used the kickstarter on other bikes to cycle the engine until TDC was found. Rear wheel spins with the Kluse. Looking to add a DirtTricks cam chain tensioner which requires the engine to be at TDC.

Remove the flywheel cover on the left side of engine and rotate the flywheel to TDC on the compression stroke (all valves closed). You can actually temporarily remove the TDC locking bolt to visually look for the TDC groove in the crankshaft, then screw in the TDC bolt minus the thick washer to 'lock down' TDC.

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