RH Cylinder missfiring

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Dec 27, 2005
I am Having trouble getting the RH cylinder firing properly, backfires occasionally doesnt seem to fire consistently, have replaced points for that cylinder set gap and checked timing, any ideas on what to do next.
First spark plug, than spark plug wire, than condensers than point wires. Than carb idle circut pluged?, main jet holder loose? Lashed your valves latley? Mouse nest in the exhast? norbsa
Recently, I had a similar problem that was hard to find.
It was one of the terminals on one of my coils. Dam thing was broken inside the coil & making intermittent contact.

Then on the way back to Brisbane from Sydney, after visiting the Hunter Valley "Norton Day".........One of my "well worn" slides had two chunks of the front of it misssing. Chewed up & spat out of the engine I'm guessing. Anyway the the engine got me home ok, as on the highway with the throttle opened up, the engine ran ok.

Hopefully your problem is simpler. As norbsa suggested, start at the plug & work back.

You wouldn't have an air leak at the carby would you ?

Follow what Norbsa listed. Swap sides with the spark plugs first to see if the problem goes to the other side. Another cause can be the coil has been pinched in the clamp and shorting internally to the case. To confirm this, take the coil out of the clamp, wrap a plastic bag around and slide it back into the clamp. This insulates the coil from any ground.
Good point David,

My coils are both "wrapped" in an old pushbike inner tube.
Then you only need to "nip" the coil brackets up & hopefully not overtighten them.
well i have just been fidiling and found that at high rpm it is fine but it is at idile there is no fuel i pulled the bowl of cleaned the idel fuel passage and the float is fine but no fix the bike runs a dream when i open the throttle so it is for sure fuel, when it is idileing i press the tickler and it kicks in and starts running then dies from fuel starvation damn thing but ohwell anytips on why it dont wanna get fuel at idile i have the needles on the middle notch would changing them do anything or hasnt that got ne thing to do with the idile?
Check your needles on a flat piece of glass. I had a similar problem a few years back that turned out that one of the needles was bent. In fact, you would be amazed at what new needles and seats will do to rejuvenate an old set of Amals.

Main and needle jets don't really affect the idle mixture.

The idle passages on AMAL carbs are prone to blocking up especially if the carbs have been left with fuel in them for long periods.

So I think you need to check that the pilot system is clear FIRST, by following the instructions here:
5. Pilot Jets.
Also check the float gasket isn't fouling the float.
Also look at: 'The pilot jet system' here:broken link removed (for some reason the float bowl is shown fitted the opposite way around to normal in the illustrations??).
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ok thanks for the help i will have to get onto clearing out the pilot jet as im sure that is wat it is and i will check the gasket.
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