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Rebuild low compression

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will not fire at all! 

I just completed my 2nd ever top/bottem end rebuild.

First one on a 1999 KX250.

Replaced all seals and bearings and cranks. Hot Rod Brand. New Namura piston.

I am only getting about 120 compression after about 7 kicks.

The engine will not fire at all, seems to be spark when I hold plug against cyl head.

Checked timing, even put a little gas down the spark plug hole and nothing.

Plug is only a little wet but that may be it is just not drawing much fuel due to low compression.

Before I pull the thing apart again, split the cases and check everything.  

Anybody have any suggestions?

Thanks in advance.

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check your carb? make sure floats are set.  The compression should rise once the rings are seated but obviously the bike needs to be rode for that to happen.  does it sounds like it wants to start at all? 

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Thanks for the quick response.

The bike does nothing, the compression guage has been used before and appears pretty reliable.

If I try to start it without giving it any throttle the plug appears dry,  Open throttle a single drop on the plug.

I am a rookie stiill, but it appears that there is not enough fuel begin drawn through the carb.

There also appears to be spark, but to me it appears weak.   Is there a accurate way to measure that?

Thanks in advance.

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