JP Single thruster set up suggestions

After a few sails on my 106LSingle thruster, I can't figure why the bloody thing won't plane! Today was the last straw. Sailing raffs of a sw 18-25 knts fully powered up. I got sick of it and decided to change to 92L Starboard Quad and had an awesome time for then rest of the morning. Has anyone got any suggestions why it would feel so bogged down all the time? Shouldnt it get going earlier than Quad?

Whats your weight? I can plane on my 93L single thruster with a 5.0m sail in around ~16knots, I weight around 72kg, and I use the stock fins (all three), I never bother using it in single fin mode, did try it once and didn't notice any difference in planabililty, but did notice a BIG difference in (lack of) turnability. Maybe its just your stance? Rig position ?

I wouldn't think it would make that much of a difference ? I have mine in the center, and my foot straps to the forward bias so that my overall weight is more forward which suits my wave riding style better. But like I said, never have a problem getting on the plane. Have to ask, is it a new board? If not has it been repaired ? Does it feel heavier than normal? With your weight, it may be worth trying the board with a larger center fin.

Stick a two foot long straight edge on the bottom of your board and slide it back and forwards. You will be able to see the flatter part of the rocker easily.
This will give you an idea of how much front foot and rear foot pressure you need to keep the board on that plane , by understanding where the flatter rocker is. Try your rear strap at 21cm, and your front at 81cm, or a couple of cm more if your taller, say 83cm. Also look at your mast track position in relation to the forward rocker curve, where it begins , the apex. It may start to kick approximately in the mast area, so the solution may mean to move your mast base back. Use the straight edge to find it, push down hard on one end, slide from the tail and when the gap increases, this is the apex, if your mast base is forward of that , then it will be pushing water, harder to plane. Relate all of this to your Quad too and you may find some differences. l think a 21cm fin would be the minimal rear fin you may need too, assuming your front fins are about 112mm high. Make sure the front of your rear fin is halfway through your rear strap or further back.
Putting your boom a little higher may help too to give more lift as well.

I mean thanks!