Hi all, I'm looking for some advice please. I'll give as much detail as possible so apologies for the write up length.

My Question is about board size (or my stance).

I had lessons 2 years ago, and purchased new (2012) kit at the time based on advice from the school. I then suffered a serious injury (unrelated to kiting) so the kit sat unused and I've just got back to full health and back to the beach. All up including today, I've been out about 11-12 sessions including lessons. No skate/wake/snow boarding experience. lots of sailing experience.

I have 12 & 15m kites with 146x45 board. I am 188cm and at the time of lessons was 105kg now 93 and dropping - and I'm not young.

I am going well in lighter winds (say 13-18kn on the 15m / 16-20kn on the 12m), I am now able to keep ground across wind and most runs make small gains upwind. My problem starts as the wind picks up a bit or I build speed (which is too easy).

On Tuesday (12m kite) I was out and got smashed continually for the first hour, continually wiping out - nearly gave up. The breeze dropped a bit and I was off, back and forth like a champ (ok there's still some crashes). Checked readings when I got home and while I was not coping it was 22-23kn, dropped below 20 for the time I was ok. I feel like I have no control over the board when it picks up, really struggle to get the edge in and it skids out often.

Today, with about 16kn (15m kite), I was fine until, I edged hard and started gaining upwind (I'm edging upwind quite easily in the light stuff), board speed builds - apparent wind increases go faster & faster ect to the point where I feel I can't get enough weight on the back foot which, I assume I need to slow down a bit and steer. I feel quite out of control at speed, and the only way to slow is to bring the kite slowly overhead. I can actually feel my front foot holding the strap by pulling up at times and the nose just doesn't lift.

Q. Is my board too big, or is my stance wrong and I should be able to make it work?

Gilly3 said it perfectly: ... remember it is your rudder. I had a similar problem and in my case I was pointing myself too much up wind and consequently the board started skimming over the water, almost perpendicular to the kite. I also noticed I was doing the poo stance, even when I thought I was leaning back.

It's sort of hard to explain, but I overcame this by [1] not looking at the kite and [2] looking where I wanted to go, compensating for speed, power and balance by edging just enough to make that rudder effect. It just takes practice and noticing all variables: stance, speed, power of kite, directions, etc. Also the conditions of the water change things dramatically and suddenly you're doing poo-stances, wobbling about, etc.

Practice!

Do not lock front knee back.Try and keep a little bend in it so you can absorb chop or you will damage your knee.
Lean back and have your butt a couple of inches off the water. If it all get to fast touch your butt on the water to slow down, it also helps in bringing the nose of the board into the wind. Try not to fly the kite up to the zenith it only makes it harder to hold the edge if any thing fly the kite closer to the water, the wind is lighter close to the water and you can dig the edge in even harder if the pull is almost parallel to the water

Hey Harlie , some big boards handle bigger ranges than others. by the sound of it your board is square in outline or low rockered or both. I have an old 2005 161x43 naish haze that will go in really strong winds but it has narrown tips and heaps of rocker.
If that's not the case with your board the issue could be your kite size as much as anything. 20kts + on a 12m kite is a lot of pull and can take up your whole sesh just managing all that. You could go on an 8m kite in those conditions and find your board is perfect.

M8, a 144 cab custom would be sick for you in the higher winds. I have m8's your weight riding around in 25kts on 142 and 138 Naish momentums that are sick boards. I ride a shinn red and it is the smoothest of the lot. Though not as 'grippy' as the others, my knees thank me everytime we go out. Another pal has a monk 132 and it definitely likes the high winds. Tons of boards out there. but the small boards generally are crap underneath the big kites, like your 15m.

I reckon anything post 2011 and 136 to 144 will do you awesome but the closer you get to 144 you'll be looking for more rocker and narrow tips to make it a big difference to your other board.
My mate has a shinn red for sale, if you want hit me up.