Hi Rich,

The tuning guide on our website is based on information from Werks Racing USA for the Werks engines we now predominantly sell.
We removed the GO tuning guides because of some stupid copyright nonsense that came to nothing a while back.

This current guide is a great tuning system for all carbs, and will work with the long needle GO carbs.
Just remember the HSN is sensitive to adjustment with the long needle system. The HSN acts more like an on / off tap than an actual metering system with these carbs.
If you lean the HSN just a little too much you will get all sorts of lean bog issues.
Ultimately this is no different than other carbs - but just becomes more of an issue with the long needle type carbs.

The guide we recommend revolves around setting the idle gap and then not touching it again. Idle speed (and therefore air / fuel ratio) is set by leaning and richening the low speed needle around this fixed reference point (idle gap).
You are only juggling two variables this way - not three. Much easier to achieve a stable idle and good tune.

Link is www.werksracingnz.vpweb.co.nz/Tuning-Guide.html