I have researched this but can't find an answer on this my sons 90 Polaris has a new stock carb and upgraded air filter. Bike will start and idle fine but as soon as I try and open the throttle it will take off and then just die. I can restart it and it takes off again and then dies again. I replaced the petcok, fuel line, and fuel filter. I'm curious is there something I can adjust to fix this problem?

Thank you for all your help

 

Check that the tank vent line isn't restricted. You can even pull the fuel cap and see if it still bogs. If it does,then check that the jets are the same in the new carb as the old one,plus if you have a clamp on filter "upgrade" as many have done this in itself will cause them to run leaner. Possible you might also try the stock filter and air box and see if it helps. If everything else checks out including good fuel flow, you may have to bump up the main jet. Mikuni carburetor jets and parts main jet slow air pilot kit

 

Thank you I'll try these suggestions this weekend and see what happens.