Hello! After a few days of half decent waves here in Sydney I've decided to ask a question for the good SUPers out there. Hopefully you can help!

I'm really struggling holding a rail on bigger waves - they were in the range of 6 to 8 foot faces. They were bumpy (Whiterock and Long Reef Bombie) and glassy (Manly yesterday) so I can't blame it entirely on wave quality. I seem to take off ok, set up for a bottom turn, carve into the turn and lean a little on the paddle, then WIPEOUT!! Fins/rails have lost all grip and I end up sliding down the face or just falling off. It feels like a spin-out on a windsurfer...

I'm riding the 9'6" Naish with Simon Anderson quad fins - medium on the back large on the front. Should I go bigger fins in big waves or is it a problem with a fish not pintail? Or is it just technique? Do I need to get more of the rail engaged by leaning forward more?

Is this impossible to answer?! Any help gratefully received!

I am looking at changing the plastic fins my PSH 12 Gun came with to an FCS quad set up. Any recommendations on fin size?

Thanks