how do I find top dead center on 1978 GS1000

[nhgsguy]

How do I find top dead center on my GS1000?
Thanks

[Nessism]

Line up the 1-4 or 2-3 T mark on the mechanical advance unit with the corresponding mark on the metal plate under the points/signal generator plate.

[YoungGunRodder]

top dead center is when the piston is between its rise and fall.

There is only a brief moment when this happens before the piston begins its way down the cylinder again.

If the engine is assembles: Place your finger in the spark plug hole and turn the motor by hand until you feel the air escape past your finger. (top dead center on that piston) The others are at a little bit different point, but finding them is all the same. Usually two pistons will share the same TDC.

If the motor is UNassembles look at the top of the piston when it reaches the head portion of the motor. turn the crank and You'll see a moment before the piston goes down again.

Hope this helped and was not confusing, First time wrote it down.

YoungGun.

[katman]

This may be obvious but there are two top dead centers in the cycle. The one described above is on the compression stroke with the valves closed and there is another tdc when the exhaust valve is open. Depending on why you need the info be sure which one you are looking for.

[bwringer]

This may prove enlightening:

http://bwringer.com/gs/tdc.html

[nhgsguy]

TDC on my GS1000

Thank you very much for the info.I was looking into the manual cam chain tensioner.The manufacturer says to bring a cylinder up to tdc,then remove the original tensioner and install the new one.

[argonsagas]

This may be obvious but there are two top dead centers in the cycle. The one described above is on the compression stroke with the valves closed and there is another tdc when the exhaust valve is open. Depending on why you need the info be sure which one you are looking for.

A VERY important point, that.


I use a pencil. Remove the spark plug and place the pencil in the hole......watch VERY carefully as the piston rises and when it stops you have it.

The last few moments before it reaches TDC and the next few as it begins its descent are important as there is not a lot of movement and you have to watch VERY carefully.

You can also fasten a marking pen on the pencil and place the tip against a sheet of paper so that it shows the exact moment the top is reached.

[tejasmud]

I have done it with a pencil before. Still do sometimes.

But, yes there is a but.

If one is not experienced in this method. The pencil can easily snap leaving one end in the cylinder. Which is a major, do I say major PITA to remove.

I did a write up on another forum where I mentioned a pencil to locate TDC for valve adjustment.

A fellow member followed the directions, but snapped the pencil, then turned the engine over a few times and the valves chewed it up is why I mention it.


T marks as mentioned.

I tend to watch the ends of cams if adjusting the valves, but that was not the OT.

[katman]

why not a 1/4' drive 6" extension, robertson screw driver, drinking straw?