As the weather has been getting colder here, the engine chugs bad until it gets warmed up. Even fully warmed and after riding it chugs at light throttle at low speeds. It's feels like a misfire, but it can't be. It sounds like it's backfiring through the carb(s).
I changed the plugs, no help. Plugs looked normal. It's not a choke issue either. Any ideas guys??? Thanks.

 

My 650 is doing the same thing. While warming up it sounds like it's backfiring through the carbs. Are you sure it's not choke related? If you find the problem let me know.

 

Is it the nature of the beast? My relatives Harley does the same thing
in cold weather. Just a thought.

 

Choke Cable!!!

 

I'm going to check my choke cable tomorrow. PrairieDust what Kawi dealer do you deal with in Halifax ? Have you been able to get Mobile 424 anywhere?

 

My 650 also does the same thing till warmed up and after that it's fine. I have been debating on taking back to dealer to have it looked at before warranty runs out. Keep us posted if you find out if its normal or something needs to be adjusted?

 

Possibly float level to hight lean side.

 

Woolfy,
What adjustment are you referring to on the carb please?

 

yes it's the float level in carbs in float bowl.the setting from factory is too lean for cold temps.also in 650 the main jet is too rich.

 

Have you attempted to adjust your float level? I don't have experience with carbs. I am especially worried about dual carbs. Does the float level have something do to with the pilot jets? I know it's the pilot jets that control the light throttle slow speed acceleration? I am afraid to touch the pilot jets on this because in looking at the service manual I thought they said if it wasn't done right it would mess up the synchronization between the carbs. Also, is there one pilot screw per carb even though the service manual refers to one screw? Also, Is backing out the screw going to richen it up a little, or is more rich by tightening the screw inward. What do you think?
It sounds like you have a lot of experience with carbs. Most of my experience is in tuning fuel injected forced induction race cars.
Are you in QC or the Province of Quebec?
Thanks for the help.