Suzuki intruder 125 vl motorcycle won't start?

Can anyone help me?My Suzuki Intruder 125 VL won't start. Its always been a little sluggish since I bought from new 5 years ago. Its broken down a couple of times then randomly starts up again a few days later. On start up however it never starts first time round. I've checked the spark plugs and sometimes they spark sometimes they don't,that's with new plugs too. it intermittent firing and doesn't seem to have the power to turn over.Bump starting doesn't work and the battery is all powered up.Does anyone have any ideas please!!!!Now though its completely died on me.