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Top Dead Center on the Compression Stroke

Hi everyone. Not long ago I did my first valve adjustment on my Zuma 125, and wow, it really improved the response and speed by doing this. I removed just about everything to do this to make sure that I was at top dead center on the compression stroke like the maintenance manual says. I’m putting it out there to you experts, to see if there’s an easier way of doing this.

I have some fancy-schmancy cooling fins on the valve covers and the breather cover and (especially that breather cover) is a little bit more difficult to remove for this procedure, but the breather/chain timer area has that cool little etched-in line that tells you exactly where the TDC on the compression stroke is.

I’ve also taken off the plastic air shroud for AC Magneto Rotor/Fan cover and it has that stationary arrow and TDC marks on the crankcase. However, it alternates between the compression stroke and the exhaust strokes. I’ve heard that some people will just remove this part and put in a chopstick or a screw driver inside the spark plug hole to see when the cylinder moves up to the compression stroke.

So, how do you do this? Is there an easier way of doing this that you recommend? Thanks ahead of time for any of your suggestions.

— Rick
 

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Top Dead Center on the Compression Stroke

Hi everyone. Not long ago I did my first valve adjustment on my Zuma 125, and wow, it really improved the response and speed by doing this. I removed just about everything to do this to make sure that I was at top dead center on the compression stroke like the maintenance manual says. I’m putting it out there to you experts, to see if there’s an easier way of doing this.

I have some fancy-schmancy cooling fins on the valve covers and the breather cover and (especially that breather cover) is a little bit more difficult to remove for this procedure, but the breather/chain timer area has that cool little etched-in line that tells you exactly where the TDC on the compression stroke is.

I’ve also taken off the plastic air shroud for AC Magneto Rotor/Fan cover and it has that stationary arrow and TDC marks on the crankcase. However, it alternates between the compression stroke and the exhaust strokes. I’ve heard that some people will just remove this part and put in a chopstick or a screw driver inside the spark plug hole to see when the cylinder moves up to the compression stroke.

So, how do you do this? Is there an easier way of doing this that you recommend? Thanks ahead of time for any of your suggestions.

— Rick
The piston will be all the way up when it shows TDC on the crank marks, what you need to do to make sure it is on the compression stroke in make sure both valves are closed when it is at TDC
 
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