Best bet is mate take your back wheels off check the calipers over and make sure there not seized first take them apart really easy to do
clean them up and copper grease them up and put them back together so long as there operating ok thats all you will need to do. However if you fancy adjusting the cables the adjuster is under the back ashtray assembly and handbrake cover 8 or 10 mm bolts on end of the cable but i can gaurantee this wont need to be adjusted inless the cables are shot. And i can bet you over winter there will be endless amount of threads on here saying my handbrakes sticking on when it freezes over night reason being is the moisture freezes inside the cable casing and the handbrake wont work or stay stuck on not good feeling when late for work
if they look old i'd replace them now there about £14 a side and take about half hour to replace and new ones dont freeze
hope some of this helps
