[raveer2000]

I have an 04 foreman S 450. It has a big bore kit on it and it was reciently sunk. The top end was redone and we had it running great, but now it won't start and run. It will run with the choke on and I have to keep it reved up or it dies. It pops and bangs out the exhaust and I can see flames shoot out when it pops. I have had the carb off and soaked it in gas and blew all the passage ways out to make sure they are clean. I have pulled out all of the jets and the mixture screw and made sure they are cleaned. I am at a loss here. The exhaust is getting so hot that airbox has melted at the bottom and the rear fender was too hot to touch. That tells me that the bike is lean. So I have kept turning the airmix screw out a half turn eachtime and it still will not richen up. Can any one tell me where to start from step one. This thing is driving me crazy. We had the bike dynoed at mud mania and the next day the bike would not run. I have no idea what they did so I am now lost. HELP

 

[raveer2000]

Also..........It has an HMF it is snorkled but not hooked up at the moment because I keep haveing to take off the carb. I have moved the clip all the way to the bottom with a washer under the clip and it will now start without the choke but will not idle. I am also getting quite a bit of grayish black smoke which tells me too rich right. Man this thing is going whacko. Can these bikes jump time or anything like that. Don't know the jet size, but it should be the recommended jet from dyno jet kit. Whatever that is. Don't know about water in the gas tank but I will drain it and put in fresh to be sure.

 

[Railroader]

Sounds like you got your hands full. Good luck.

 

[bnjeep]

If all of that is not changing the amount of fuel that you are getting, then maybe it is something between the fuel tank and the carb. If it is possible I would try and borrow a carb off of another bike and try it, see if it makes a diff. I hate it when things just don't make sense drives me nuts. Good luck.

 

[REDDOG]

Make shure all the vent lines are clean. Don't for get the vent for the fuel cap. Make shure the cap is not the problem also.