Fouling Spark Plugs

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I have driven 20 miles on my bike and I am already on my second set of plugs.

I have a single JS Motorsport carb, and a Boyer ignition. Everything else is stock.

My plugs are black and sooty, so I assume I am running rich, my timing has yet to be verified by a timing light, buying one tomorrow if I can find one in town.

If I am running rich, should I turn my air mixture screw in, or out? And would my timing cause fouled plugs?

I am going to change the oil tomorrow, I will make sure not to over fill it, as I know this can cause the issue as well.

One other issue, seems to be noise coming from the top end of the motor, just a clinky nose, doesn't sound terrible, but I have no idea what a Norton is supposed to sound like, so I am a little worried.

When it is running, it has lots of power, lots of speed and it so fun to ride.
 
If I am running rich, should I turn my air mixture screw in, or out? And would my timing cause fouled plugs?

clean the plugs good again then.....

turn it out to start another quarter turn, then start the bike and take it out for a run up to say 5000rpm and shut the throttle off, if the motor pops on deceleration then turn it in just a little bit to stop it, perfect

if that still won't stop the plugs fouling then I think you need a leaner pilot jet from Jim Schmidt

as far as the timing goes, I like to advance it until it kicks back on start up then retard till it stops, that should put it pretty close if you don't have a strobe light, but I don't think timing is fouling your plugs, you are too rich on the air screw/pilot jet configuration
 
I really don't think that you can time a Boyer without a timing light, depending on the model Boyer used the timing is not linear at low revs. They should be timed at the F mark at whatever revs your Boyer stops advancing, usually around 4500 revs.
 
Use NGK BP7ES plugs, or BPR7ES, Not the 8s. If you use Champions use 4s not 3s

A lot of the older books recommend the cooler plugs.
 
You should also check out the Boyer wiring as what you describe is also a symptom of low voltage at the black box.
 
>>One other issue, seems to be noise coming from the top end of the motor, just a clinky nose, doesn't sound terrible, but I have no idea what a Norton is supposed to sound like, so I am a little worried.<<

Clinky noise from head sounds pretty normal for Norton, however if valve to rocker gap a little big will sound more that way.
As iron barrel and aluminum pushrods warm up any noise from valve to rocker gap should go away, if correctly set since thermal expansion rate of aluminum is greater than iron.
 
So being a carb newbie, my air screw on my carb should be screwed out to l lean out the air fuel mixture right?
 
If this bike is new you I would put all new jets in the carbs. Standard if stock air cleaner and pipes. Needle jet and needle probably worn but you won't know if it is even jetted correctly. Start at standard jetting.
 
The carb is a brand new JS Motorsports single 34mm.

I lowered the needle today to see if that will solve my issues and lean it out a bit. Other wise, I might have to order a new jet from Jim.
 
Oops I missed that bit. Thought you had twin Amals.
I'd drop Jim a line and see what he recommends.
 
jesterday said:
My plugs are black and sooty, so I assume I am running rich, my timing has yet to be verified by a timing light, buying one tomorrow if I can find one in town.

If I am running rich, should I turn my air mixture screw in, or out? And would my timing cause fouled plugs?
The air mixture screw meters air, so opening it will lean out the mixture. But, you have to bear in mind that the different parts of the carb control mixture at different throttle settings. The air mixture screw and idle jet have their main effect only at low RPM's. Also, getting a reading off of what are now fouled plugs isn't always predictable. You might not be able to burn off the residue after you correct the jetting problem. Put in clean or new plugs to read.

Think about dropping a line to the INOA chapter near you. There may be some Commando owners near you with advice ect.

http://www.inoanorton.com/Chapters/index.html


Fouling Spark Plugs
 
as far as the timing goes, I like to advance it until it kicks back on start up then retard till it stops, that should put it pretty close if you don't have a strobe light, but I don't think timing is fouling your plugs, you are too rich on the air screw/pilot jet configuration

Ole obnoxious Iup does know his Norton boyah's best protocol, then go put a light on it to record objectively somehow, after you have put degree wheel on crank to know what the alternator marks and factory gauge are really indicating, or time light may mislead you to ping or over heat. If was Amals i'd try lowering the needle and or float level. If ya think its coking up can clean out by water spray while blipping.
 
I am going to get new plugs tonight. I dropped the needle, and give it a go. I bought a timing light and everything seems fine. I will have to get a degree wheel to verify the markings on the bike though.

Thanks guys.
 
most important, what is Jim Schmidt telling you to check into to solve this problem?
 
Jim suggested I order the .099 needle jet, since I dropped the needle, I haven't could a plug, but I did order the new needle jet as it is still running a little rich.
 
Jim knows these carbs very well.
I suffered from the sooty plug disease when I first got Vivian (my cdo) with a Mikuni VM and carried a pocketful of clean plugs and a spark plug wrench until I got the (Amal MkII) carburation dialed in by trial and error.
 
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