Mac,
First of all you can test continuity across the condensor, but if you are getting any spark you're passing that test. The whole set-up is cheap. See
http://www.re-mx.com/cr/cr125_cr250.php for tune-up kit and more. Get a few plugs.
On your carb question I would have to say you need to tear it down and get a good carb cleaner into the shut off valve and all the little venturi (passages). Make sure your float actually floats. Reassemble and try again.
Dan
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Re-MX, Inc.
OEM Honda & reproduction parts for vintage bikes
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