2003 pro X 440 fan

[confusion_900]

just wondering if anyone has had any low end bog on these sleds
and yes I cleaned the carbs real good !
the boots from the air box do look loose around the carbs but on the high end
it pulls about 7700 rpm's.

 

[trailshredder]

Hows the belt to sheave clearance on the primary. Should be around .010. If your belt is sloppy in the primary that would cause low end bog. Just a thought for you to look at.

 

[garageguy]

These sleds are reall sensitive to warmer temps. I put a Holtzman Tempa flow in mine to solve that problem. I would try a new almound primary spring, drop the pilot jets one size,and 2.25 turnes open on the air screws. The Almound spring has a higher engagement and will help you get past the low end stumble

 

[confusion_900]

Hey Garageguy, I have 39 s in it (stock 42 ?) and the air screws I have tried from 3/4 to 11/2 turns out
I wouldn't even think to go that far out

the stock spring that is in it ( white ) it engages at around 4200 - 4500

 

[indy_500]

Clutch Springs worn out? You can test them with a cordless drill and a scale

 

[snowbuff]

There is nothing wrong with turning your air screws to 2.25.

 

[garageguy]

Here is my set up. Primary, almound spring, 10-54 wieghts. Secondery red spring, second hole. This will give you 4500 engagement and full shift at 7800.
I would try 320-330 for mains depending on how cold it is. .035 for pilots and 2.0 turnes out on the air screws. If your low speed stumble happens mostly on warmer days, I would drop the needles one, on those warmer days. I have 17000 mi. on my sled and tried everything to get rid of the stumble. This set up worked the best, untill I went with the Holtzman tempa flow. You could also enlarge the hole in the hood where the cooling air exits the motor, I found that will also make a difference.