Ok, hence the double taper which is really a flat line with a taper at the end. (The GT90 has only 10’ of taper).
Then along comes the WF which on the face of it introduces a reverse taper into the middle of the line which should hinder energy transfer?
Which takes us back to Moray's post
Both those line hit their rear taper at or about 30’ with the SLX having a very short belly (flat line) giving you only 3’ after 30’ before you're into thin running line.
It really sounds like you shouldn't have more than 30' of line out for either doesn't it?
I think some explanation of how fly lines 'roll out' is needed here. Now this is a contentious issue and there's an awful lot of bollox written by people who think they understand it (and the underlying physics) but actually they're just in the business of flogging tackle.
'Energy transfer' is one of the terms that just leads to confusion. I think most people with some common sense will agree that the (kinetic) energy of the line is at a maximum immediately after the fly caster's input is finished i.e. once the line starts overtaking the rod tip. From this point forward the only thing that happens is kinetic energy loss, ending ultimately with the line laying out possessing zero KE. So the key thing is how this KE loss occurs - and how the fly line taper affects it.
I don't want to turn this into a physics discussion, I think that's best left for Sexyloops, but if someone wants some additional reading they should look up the conservation of energy laws, particularly the conservation of angular momentum.
What angular momentum considerations will tell you is that a spey type taper (triangular) will turn-over quite 'aggressively'. This is great especially for roll casts etc. where you want to lift the anchor out of the water and deliver it to the target. The reason I don't like them for overhead (distance) casting is because this 'aggressive' turnover results in the cast straightening too early, and once the line is straight the forward shoot is compromised.
For distance casting therefore, I want to slow down the turnover in order to maximise the flight time. This relies on the opposite angular momentum effect, i.e. if the line is going from thin to thick as it rotates around the loop it will slow down. This is exactly why distance casters want to cast with overhang behind their WF heads - this means there's a transition from thin running line to the thicker head. This means the turnover of the head itself is slowed and (hopefully) the line straightens just before it touches down. Getting this overhang correct is a skill that all good distance caster master.
Going back to the GT90 line in the example above, if you really wanted this line to cast far you'd aerialise it right to the end of the rear taper, i.e. carrying 70ft plus of line. Very, very few caster possess the skill required to do this though.
James
