I have a 1995 arctic cat 580 ext carb. The sled came stock with 340 jets. I bought it used and it had 320 jets. If I ride it it seems fine as long as you vary the throttle. If you ride it consistantly above about 25-30 mph for a while it seems to bog and acts like it is flooding. It seems a little better if I drop the needle all the way. The carbs were just cleaned and synched. Now when my son rides it it seems to be worse and will bog earlier and does foul the plugs. Also before I dropped the needles it fouled the plugs but the sled would do 90-95 on the lake. Now it seems to fall on its face around 50-60. I have been advised to drop the jets to 310's because the sled needs to be leaned out. I think I should first try going back to stock 340 jets. I need some input here. There is no indication that I am running too lean but I think that the plugs are fouling because the oil pump is set at the factory setting and if I go back up on the jets I will be back at the factory set mix. All the rest of my sleds are still set with the stock jetting and I do not have any problems with them. Any input would be greatly appreciated.
