Remove delay during map execution

I have the following map which inserts a space and escapes back to normal mode. How can I remove the delay associated with it when I execute it? I want it to run immediately when I press the comma key in normal mode, but there is a delay (to determine if this is a leader character, I think). For this mapping I do not want any delay. I have search through help for a setting that will remove the delay but have found nothing.
 
nnoremap , i <ESC>
 
Thanks,
Roy