got some details on this carb set up
Sure stock carb on Honda is 15mm open port hole.
This Honda CH80 carb is 18mm open port hole.
The jetting is stock but can be upgraded.
I have the user manual in PDF format if you'd like a copy.
It fitting together perfectly with the 18mm intake manifolds from http://www.motorparts4less.com/products.php?id=38.
Several changes to the carb needed to adapt to gxh50.
I should have test results in a week or two.
Give me an email and I'll email you the user manual if you want it.
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