I have a '78 kz650sr still runs great but cold blooded as hell I have to sit there with the choke wide open for about 10-15 minutes thengradually shut the choke offanybody have any suggestions what to do to remedy this? already changed plugs and wires....any help is much appreciated

 

Is everything on the engine stock? My KZ750 always had a hard time warming up too, but it took maybe 4-5 minutes on a cold day before I could un-choke it.

 

yup everything is stock