Carb issue i hope

For the past week my engine has been running like garbage to were i cant drive it, it jerks and hesitates like its not getting fuel, the carb that is running on it is a road demon 600 and it only recently started running like this, i checked the plugs and they were a bit pinkish black so i cleaned them and installed them no change so i installed another carb i have which is a 750 summit 4 brl and the problem was still their, so i pulled that carb off since i didnt want to run that big of a carb on my setup for too long and pulled the plugs again this time they were black so i bought new plugs installed those and through the 600 back on and it ran fine at idle but after a few min of driving the problem is starting again, i do not no much about carbs so please be very descriptive thanks

 

If your plugs were black that means the carb was very rich. Is your ignition system working properly. If you still have points are they adjusted correctly and was the timing set after the points were set?

 

so you have points or a more modern ignition system? if you have points check them make sure theyre making spark and check your coil.
Im leaning towards something in the ignition system check to see if you have any loose wires
I dont think its your carb since you changed it and got the same results the plugs being black is carbon or left over gas meaning its running very ruch like youre getting a weak spark or none at all at times
I cant say for sure without knowing more about your car
hope this helps some how

I car did that recently and we come to find out the gear on my distributor was coming loose as the pin that holds the gear on teh bottom of the shaft was cracked and allowing the gear to move around a little causing me similar problems especially when I tried to get on it

 

i installed another carb i have which is a 750 summit 4 brl and the problem was still their,

So the problem is not the carburetor. Do as junrai suggests next.

 

Yes i have points and they were adjusted after the timing, im thinking about going electronic,

 

You need to adjust the timing last as points adjustment will change the timing. If you have a adjustable timing light you can see if the timing is moving erratically when the advance is all the way in. (revving from 2800 - 4800 rpm there shouldn't be much change.)

 

Might be a fuel pump issue!

 

Or old rubber fuel lines or in-line fuel filter.

 

Don't even consider going to an electronic system until you get your problem solved. The issue may not be the ignition system.

 

Ya im going to try a carb off my brothers comet that i no works so hopefully it will be the carb