Your looking at a major service which will include checking your valves, adjusting your timing on your trottle bodies, checking the plugs and so on. Tell ya what!....go to the file vault and check out the service manual for your year of bike in the periodic maintenance chapter, it will tell you everything you need to know.:thumbup
DON'T MISS THE VALVES OUT!!!!!!!!!!!!!!!!!!!!!
15k is a MAJOR service so valves need looking at. Ninjas are notorious for needing shimming, especially at first major (8k) and USUALLY are ok after that BUT get them looked at.
Tune up's depend on budget really mate, but usually go along the lines of race can or full system for ultimate power gain. Then go for air filter upgrade and Power Commander to map the fuelling on your bike perfectly.
Well, i work at Kawasaki, so my parts are a little less costly now, but how hard is it to shim the valve's I've never heard of that, ( I'm a Honda car motor guy ) but i'm very capable of turning wrenches, it just looks a little tedious after seeing the shims at work...
Shimming is the ONE job on my Ninja i leave to the experts! Depends on make / model but usually either requires total removal of cams or you'll need to buy a specialist tool to remove shims from under cams in situ.
I think total service time for Major service is around 3-4 hours. Less, obviously if you do some of the work yourself, ie. grease rear linkage, change oil + filters etc.