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Should you still have to use the decompression lever on the compression stroke if no spark plug is in the bike or should it turn very easy?

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With no plug, there's 10mm hole in the top of the head, so the engine is incapable of generating any compression.  The answer, then is obviously that the decompression lever is both unnecessary and should have no effect on the matter.  It should be easy to turn over.

 

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36 minutes ago, grayracer513 said:

With no plug, there's 10mm hole in the top of the head, so the engine is incapable of generating any compression.  The answer, then is obviously that the decompression lever is both unnecessary and should have no effect on the matter.  It should be easy to turn over.

 

it alternates. it will turn over easily with one rotation of the kickstarter and then the next time it will get very hard eventually to the point that i have to use the decompression lever to make it move. So thats not good right?

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1 minute ago, grayracer513 said:

Is that with the plug in or out?

Plug out

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What you are suggesting is that is not possible as you state it.  Without anything in the spark plug hole, compression cannot resist the bike turning over, and the compression release cannot relieve that situation because there is no compression to release. 

With the plug hole closed, it is not unusual for the older engines to have very little compression at times, yet good compression at others.  This can be caused by dry rings, but is most often the result of a valve sticking part way off its seat due to carbon on the valve stem or too close to the edge of the sealing face.

There are mechanical conditions that can cause the engine to be difficult to turn over with no plug, such as damaged starter gears, but the compression release cannot affect any of them.

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