Originally Posted by vtloon
. . . Because the spool radius is in effect the lever arm the fish uses to start the spool turning (and the drag dragging), the large and very-large arbor designs allow for a smoother drag initiation, so they are progressively more desirable with fish that accelerate rapidly (and hard) to a higher speed. i.e. bones, tarpon, albies.
Why do you say this? A larger lever arm means the resisting torque of the drag must be greater than a smaller diameter spool to achieve the same resistance (drag) on the line. So for two reels having the same drag system but one being conventional and one being LA design, I'd think that the conventional reel should have a smoother startup because it's drag does not need to be clamped down as hard (greater friction is required to achieve the necessary greater torque) to achieve the same resisting force on the line.
By the way, startup inertia is the same as the inertia when the spool is spinning. I know it's a commonly-used term in the industry, but it's a peeve of mine (grain weight is another). The correct term would be startup torque.
With respect to inertia, actually the moment of inertia, a larger diameter spool will have more mass concentrated further from it's spindle and thus be less be more resistant to starting up (accelerating) per Newton's second law.
I'm not disagreeing with you, but simply saying that because the lever arm is greater doesn't explain your claim that drag initiation would be smoother. Could you elaborate?