longboard slipping on bigger waves

[iTread]

I just picked up a 9'10 long board with a single fin.
I took it out yesterday on 4 to 5 surf, decent size, steeper faces.
I normally surf a 9 foot board that I can pump up and down the face easily.

This new board kept slipping on the face.

I noticed the tail of this new board has more rounded edges.
Is that the problem?
Is the single fin the problem?

If I got a longer fin would that help?

Thanks

[waikikikichan]

Some remedies:

1) Put your back foot further back on the tail ( when making turns, including a bottom turn on the take off ). You need to do a bit more moving back and forth with a single fin versus a thruster set up.

2) Don't push too hard too early. With single fins, you have to wait for the fin to "load up". If you try to force it, it will slide out or track straight and buck you off. Square peg in a Round hole. Riding a single fin will teach you patience and to listen to the wave.

3) If it's a single fin in a center box, align the fin in center of the box. If you can't turn it, move the fin forward 1cm. , then more if needed. If the board slides out, move it back 1cm. If it's at the end of the box and still sliding out, you need to get a bigger fin.

I noticed the tail of this new board has more rounded edges.

Is your board a 50/50 rail ?

Is the single fin the problem?

Are other surfers at your local break using similar sized board with a single fin ?

If I got a longer fin would that help?

I don't know, because you didn't say what type, length fin you are currently using. What make model type and size is it ?