My Bear Tracker 250 would not run well. It was cutting out and seemed to be starving for fuel. I took the carb off and cleaned it with carb cleaner and put it back on. Now it will not run at all. Fuel is getting to the carb and there is a new air filter on it.

Check, clean fuel filter. Check fuel pump for correct pressure, by opening and catching fuel in carbs. If carbs. are consistant with plenty fuel. You will need to clean carbs. Firtsly check for air leaks, by spraying carb cleaner on fuel lines from tank to carbs. If engine speeds up you found air leak

The timing is not adjustable. I would start with a clean air filter, clean carb, good spark plug, check and make sure that your cam timing matches your flywheel.

It's starving for fuel.

Sounds to be the float and needle needs replaced. The float raises the needle to let gas through the carb. If the float isn't working properly the carb starve for gas. If replacing the float, be sure to clean the carb to.

Time for a carb cleaning. Take off the carb, take it to someone with a sonic cleaner. Change your spark plug, clean out your tank (Take out the fuel shut off valve before you do this as there is a very delicate filter on the shut off valve that could be damaged otherwise), and replace your air filter. How long you want this repair to work is directly dependent on how well you clean everything. Even if you do a perfect job on the carb, a dirty tank will take it back out in a matter of minutes. a dirty, fouled or weak spark plug will hinder your efforts, and the carb cannot mix air it is not getting.

clean air filter, and clean carb with spray cleaner.make sure carb choke is free to move.look for vacuum lines off or stopped up. if trash is in the carb just draining it might not be enough,you may need to clean the jets or float needle valves too.

Check your main jet it may be blocked .

you shouldnt have to resync the carbs as long as you dont touch the mixture screws or the screws for the throttle blades. you wont have to pull the jets completly out to clean them just spray the heck out of all the orifaces with carb cleaner once you have them pulled apart. Also whe you put it back together make shure the carb seal to the engine and airbox are tight with no leaks, this will make it run bad also

blocked carbs, get a good fuel system cleaner, if you in USA get Berrymans B12, double the dose and mix in tank. run til hot then leave to stand overnight. also if you can remove the air cleaner to get to carb intake, get spray carb cleaner an chuck a load in there. also check to see if you have a fuel filter inline