Superfish submenu doesn't stay open on a tablet./mobile

Hi,

I hope I'm on the wright forum, sorry if not.
I use a template which uses superfish.js for the menu.

The submenu doesn't stay open on a tablet.
What can I do to leave the submenu on a tablet longer visible?
see: http://www.extraleisure.nl/advies on a tablet.
Please give me an example because I don't know js.

I tried to set sf.defaults delay from 800 to 2000 but this didn't work.