Just found this on another forum....

-------------------
I had exactly the same problem, the thing that finally fixed it after replacing plug, leads, dizzy and rotar arm was a huge battery! My exsisting one was a 60 so i put a 95 on it(much bigger in size but still fits) and now it starts first time.
I think the problem is when its cold the cold start injector is injecting, so if you have a weak spark it doesn't ignite. After turning over for 20 secs the odd 'nearly' splutter is enough to evaporate the flooded cylinder and fire up. Bigger battery and new plugs etc will give it that strong spark to start. Mines fine now...
Should save you the embarrasment of pushing your valver...
-------------------
gona give it ago...