KLE 500 Valves

Have scanned through all the posts here and not found any posts relating to starting problems  with a cold KLE 500.  Have had 60 000 trouble free KM's on mine apart from two occasions when I have had problems starting when the engine is cold.  Both occasions were related to valve adjustment.  The bike has been services on a regular basis and to my knowledge the valves were checked.  The last time I  had the problem I took it upon myself to set the valves.  Not hard to do but a little fiddley.  The bike is running like a dream now and fuel consumption is about 230 km's before I hit reserve but sounds a little rattly.  Could this cause a problem down the line maybe?  I did set them according to the spec.