My GS850 with an SU HIF38. I had a 44 on it for years, but gasflow was rough at the lower end, so a couple years ago put this on - pulls like a train now up to 90+mph. The manifold (ex Avenger with 'zuk flanges) is good for 115mph in cfm terms, which the 44 could do.
Yellow spring, ADR needle, 30mm thick K&N pancake, stub stack. The combo of all those things works on this engine.
An overview of the installation, with daft little pancake filter - thrown in the bin, as it was strangling the thing...
The K&N element, which had been on the HIF44 from day one...only reason I didn't re-use it was lack of fitmentalityness; soon solved that.
su/stromberg carb on a guzzi le mans