I've done a lot of googling but can't seem to find any proper resource for determining which size board for sup surfing.
I'm 86kgs just under 6' 60yrs old, pretty decent shape, surfed longboards all my life, wing foil etc & currently have a 10'6 x 32 170L which I'm paddling trying to get onto knee to waist high waves.
I find the 10'6 a bit of a struggle to turn to get into position to catch waves so wondering if a smaller board would assist.
What size board would you recommend for someone transitioning to sup surfing.
I'm not after performance so much, I'm all about the glide... Any help appreciated. I'd be looking at second hand boards at this stage.

Yes, a shorter board will turn much easier on a wave, and when you are trying to position for a wave. You are smart to shop for a used board for now while you develop your skills and figure out exactly what you are looking for in your SUP riding.
Based on what you wrote, I think you might look for something around 9' to 9'3" X 31.5" to 32" wide. A common tool is to figure out the liters by using the 'Guild factor' which uses your weight in kg times a number corresponding to your skill level. According to Whitney Guild who developed this commonly accepted system, a beginner would use a Guild factor of 2 which would put you at 172 liters like your current board. Guild suggested a factor of 1.7 for intermediates which would put you at 146 liters. I think something between 145 and 160 liters might be a good next step for you. You could go lower or higher depending on how glassy or choppy the conditions you ride in.
If you are looking for glide in smaller waves, look for a board that does not have too much rocker and has hard rails in the rear. Just for a reference, something like the Sunova Ghost in a 9'1" X 32" @150 liters might be pretty ideal for you since it is designed for maximum speed and glide in small to medium surf.
The fins will make a huge difference in how a board turns on a wave and how easily it pivots to position for a wave. You might try 4.75" to 5" front fins and around 4" in the rear to make turning and pivoting easier.
You might already know this, but here are some hints for turning to position for a wave. If you are standing in a side-by-side stance, it will be very hard to pivot the board around. For quicker pivoting, switch into more of a surf stance with your back foot reaching back towards the tail which you can use to drive the tail around quickly to line up for a wave. The wider you can sweep the paddle out will help a lot. Developing a cross-bow stroke is also a great skill for quickly maneuvering around the line-up.
Hope this helps.

I found 10.6 and 11 longboards difficult to turn around in waves ..well just slow ...as its still a big board ....sunova make lots of performance longboards ,if you are still learning ,be careful not to go too small
A friend of mine still rides his 9.5 x145 litre Sunova steeze .he also has ridden longboards in his past .you will eventually go smaller .probably a 9 which is a typical longboard size
9 x 30 or 31 wide would be a size you will end up on .if your able to take the leap go the 9 revolution ,or surf. the shaper Bert of Sunova is a longboard so lots to choose from .check the site .
You really could ride any 9 foot board now .doesn't have to be a longboard shape .

Tardy said..
I found 10.6 and 11 longboards difficult to turn around in waves ..well just slow

I had a 125 liters 9'11" board, and it was quite nimble for turning around before waves (and on the waves) by reducing fins.
Either a single finger fin, or a thruster setup with the center moved forward to the max:

Hi Micro

Welcome to the wonderful world of SUP surfing!

I don't spin toward the beach to catch waves.
If the wave is at 12:00 on a watch face and the beach at 6:00, I stand outside with my nose aimed roughly at 2:00
I sit just slightly wide of where I plan to catch the wave
When my wave comes, I start paddling on my left side and never switch paddle sides.
I time my paddle so my board has turned to the desired angle as the wave arrives.
This eliminates over turning as I paddle for the wave... and the need to switch paddle sides.
That switch will cause me to miss the wave in many cases as it upsets the trim speed as I paddle for takeoff.

If you go to my YouTube Channel and watch almost any video, you will see me doing this because I usually include some paddling for waves in most videos.
youtube@rickweeks

It becomes natural as you adjust to SUP surfing from prone.... enjoy the ride!

Rossall said..
If you are jumping down from a 10'6 x 32 170L board to a more surf SUP shape I would not recommend going too small too soon. I would pick up a 2nd hand 140 -150 ltr board 9 ft ish by 31 / 32" . If you settle into it quickly you can always move it on and drop down a few liters. Board like the JP surf wide, Starboard widepoints, Sunovas and Smik's Twin all are great and offer something in that size which you should be able to find 2nd hand locally.

Phil

Thanks Phil

Microsurfer said..

supthecreek said..
Hi Micro

Welcome to the wonderful world of SUP surfing!

I don't spin toward the beach to catch waves.
If the wave is at 12:00 on a watch face and the beach at 6:00, I stand outside with my nose aimed roughly at 2:00
I sit just slightly wide of where I plan to catch the wave
When my wave comes, I start paddling on my left side and never switch paddle sides.
I time my paddle so my board has turned to the desired angle as the wave arrives.
This eliminates over turning as I paddle for the wave... and the need to switch paddle sides.
That switch will cause me to miss the wave in many cases as it upsets the trim speed as I paddle for takeoff.

If you go to my YouTube Channel and watch almost any video, you will see me doing this because I usually include some paddling for waves in most videos.
youtube@rickweeks

It becomes natural as you adjust to SUP surfing from prone.... enjoy the ride!

Great tip thanks. I've watched a few of your vids & they're great.
I also notice your front foot is pretty much locked in & you shift just the back. Is that because most of your boards are shorter?

Thanks for your feedback on my YT vids, I greatly appreciate that!

On most of my boards I simply move both feet back a bit when I take off.... that puts my back foot over the sidebites and my front just behind the handle so it doesn't have to move very much.
I ride boards from 8'5 to 12' but mostly 8'8 to 9'2