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Discussion Starter #1
Okay I feel kind of dumb asking this cuz I feel like I know the answer and I'm sure it's been asked a hundred times but I couldn't find it. I know when adjusting the valves it says engine should be top dead center on compression stroke. Is there a top dead center exhaust stroke? When both valves are closed then that should be TDC on compression stroke correct? It's kind of hard to see the position of the cam lobes so I can't really go by that.
 

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You're on the right track.

Yes, there's a second TDC on the exhaust stroke.

One easy way to tell is to put your finger over the spark plug home. On the compression stroke, air will escape past it. When it stops, you're near TDC on the compression stroke. If you need to be exact, a wooden dowel in the spark plug hole can verify when the piston is at the very top of its stroke.
 

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There's TDC at the end of the compression stroke and TDC on the end of the exhaust stroke. They are one turn apart on the crank. (The crank turns two complete revolutions to complete all 4 strokes)
Watch the adjusters opening and closing the valves to see which TDC you're coming up to.
Remove the plug, put something like a drinking straw into the cylinder to feel on the top of the piston to see when it's at the top.

Or....eliminate all the guesswork and remove the camshaft sprocket cover and use that mark. If the mark is at the top, that's TDC on compression, because the cam makes one complete revolution for all 4 strokes.
 

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Discussion Starter #6
So there are 2 marks and then a "T" (I guess) with 1 mark to the left of it. Should the crank mark should be on the mark to the left of the T ?
 

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Discussion Starter #7
So there are 2 marks and then a "T" (I guess) with 1 mark to the left of it. Should the crank mark should be on the mark to the left of the T ?
 

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I could be exactly wrong?
Yes!

With the crank mark in this position the mark on the camshaft sprocket could be either at 12 o'clock or 6 o'clock.

If the camshaft mark is at the 6 o'clock position, the exactly wrong position, both valves are open at the same time.
If you adjust the valves with the camshaft sprocket at the 6 o'clock position when you start the engine it will make a lot of noise.

If the camshaft mark is at the 12 o'clock position, the exactly right position as pictured, both valves will be closed and all will be well.

Both valves being open at the same time is called "valve overlap". The greater the overlap the higher performance the camshaft and the "lumpier" the idle.
 

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Discussion Starter #11
O,duh....My bad. I just didn't understand what u meant. I have always thought that if the crank and cam marks are lined up then that would in fact be TDC on compression. Guess I should have just said that 1st. ��
 

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Discussion Starter #12
So I did the feel/see test on the piston being TDC and that did line the cam mark up but the crank mark seems to be off. Is this OK? IMG_20170531_191801339.jpg IMG_20170531_191801339.jpg
IMG_20170531_191950137.jpg
 

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