RE: Need help choosing an engine
PPPlum,
The carburettor ST equip their engines with, allows the user to adjust the mid-range mixture setting; by loosening the retaining screws and rotating the spray-bar.
This causes the 'eye' to change its orientation, relative to the air-flow through the venturi.
This in turn changes the fuel-curve as the throttle is opened.
Making this extra adjustment is not a 'piece of cake', like turning a needle-valve; so it is often overlooked by owners of these engines...
Probably also because it seems to be missing from [link=http://manuals.hobbico.com/sup/sup-manual-v1_1.pdf]the manual[/link] - I cannot find it there!
Unless there was a change lately, ST engines are not made by Sanye (the producer of ASP and Magnum), but rather by the company that makes Tower Hobbies engines.
And the OS.46AX is definely not the best engine - not in my book and not for most people who undestand engines well.
Perhaps it is the easiest for a beginner to handle, though.
EDIT: Wording.