I've found the clutch cable needs adjusting once it gets hard to shift into first or reverse. the biggest pain is getting down to loosen that little nut with an open ended wrench. the wheel is easy to move. also, if you have the stock airbox in there its an even bigger pain to access, especially in a B13.
I replace my p11 primera clutch two year ago,never had to adjust it once yet,pita to get to the 10mm adjusting nut also on a p11,same here removing airbox makes it alot easy to access.