Spark plug fouling and extremely rough running.

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Hey, I have a 1972 Fastback that has been sitting for almost 5-6 years :cry: . I got her running and ever since she started running she has fouled every plug I have put in it, and the engine will not rev over about 3-4 grand, the more throttle you give it just sputters. By the way the plugs were always soaked in gas and pitch black after I ran them. I have a big feeling it is way on the rich side, but I don't know how to adjust the carbs. the carbs are the stock amal carbs. I would just like advice on how to tune the carbs, if they are the problem. THANKS :D

5 or 6 years and it just woun't run aeh. Go to the phone order rebuild kits with brass viton tiped float neddeles. Before they come go to the auto parts store and score a can of carb cleaner. Pull the float bowls and the air filters and the air screws at a minimum. Take the little red tube that comes with the can and stick it in the hole were the air screw was. and blow. Watch were this comes out and the flow rate cause you need a pair of carbs they need to match. When you see it flowing well out the hole near the back of the throat, block it with your finger and make sure it's flowing out the tiny hole in the throat of the carb. Now replace the o-rings on all four adjusting screws there tight but don't use a tool that will cut them as you put them on. When your at the parts store get a small tin of o-ring grease too. The air screws are easy 1 1/2 turns off the seat to start. Now the slide adjustment screws need to go back were you found them so count the turns out and or take carful note of the size of the opening at the engine side of the slide so you can get back in the ballpark.Clean , clean and than clean again reassemble always thinking about a matched pair on all parts and adjustments. If you find little solid white nylon float neddles that was your problem most likley. Check float hieghts to speck sheets. If you really need it to run well you need to buy new neddles and neddle jets most likley. These are the highest wearing idem in any carb. norbsa
Sounds just like how my bike acted when the float stuck. To fix, follow norbsa's instructions above. He's got it covered. I think that will get you going!

fouled plugs

You might want to make sure you are not using the choke backwards. Cable pulled tight is CHOKE OFF. Cable relaxed is CHOKE ON. Make sure air filter is clean. Once running, shut off choke and hold throttle to warm.
Ed Ostack
sooty plugs

Norton motorcycles carbon up and must be manually cleaned. This process
is called de-cokeing or decarbonising and involves diassembly and cleaning of the top of the pistons, cylinder head and valves.
Thanks a whole bunch, I will clean the carb and rebuild everything, but first I am just going to clean the carbs and tune them a little bit. If that doesn't work I will rebuild it with new parts. :D THANK YOU for the very fast response time also. GREAT FORUMS HERE :D :D :D
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