sportsman 700 run bad in cold weather backfires and rough idle any sugguestions

 

How long do you let it warm up and how long do you use the choke for? 4 strokes are a little harder to keep running when cold and they need to let warm up for a while. At least till operating temp is reached.

 

I have the same problem.....Both my 700's do it. Especially when it is cold and snowing. Either they get a litle ice in the carb or maybe they need to be rejetted for colder temperatures.....

 

Don't know if this will help.....but....

My Boss isn't too cranky. It will fire on full choke, run it a few seconds, and then it runs nicely at half, or usually no choke.

However, my wife's Magnum is pretty cranky, as we discovered soon after we bought it. I was afraid we would burn a starter up really quickly, because we had to crank and crank and crank and crank for it to start.

Finally, we figured out this particular machine's "routine." Full choke, switches on, full throttle (down and immediately back up), and start. She cranks easily if this routine is followed. Then we run it full choke until it starts to roughen, then half, then off choke.

My point is this: Maybe your SP700's have a "routine" like this that you need to discover.

Larry

 

I think the twins were simply jetted to lean from the factory with the Pilot jet. Not neccessarily the Main jet.

 

My 04 700 was doing the same thing. I would let it warm up for almost 10 min, and it would still cut out at low RPM. I took the brass plug out of the carb and turned the mixer screw all the way in then back it out 3 complete revolutions. Now it takes 5 min to warm up and no cutting out or hesitation. I also have a K&N filter, so mabe with the paper filter you need 2.5-2.75 turns out.
Hope this helps