Beast and the carb

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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spookefoote1956
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Re: Beast and the carb

Post by spookefoote1956 »

I've bought the shim kit in case it's needed.
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All my bikes are original........ to me!
"Creativity is your intelligence having fun" Albert Einstein
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spookefoote1956
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Re: Beast and the carb

Post by spookefoote1956 »

So this is where I'm at. I've reset the timing and it seems to be trying a lot more. I've checked the carb float with the tube and that's fine. I am however concerned about the Spark Plug. It is one of those fancy NGK BR8IEX Iridium things. I've ordered some BR7ES and BR6ES plugs incase that iridium stuff is too much. It could even be a fake plug as I bought it off fleabay and apparently this can happen. Incidently, I popped into Halfords and was totally shocked by the naff selection of plugs. It's a modern world!
Hail Joe Lucas ............ Prince of Darkness!
All my bikes are original........ to me!
"Creativity is your intelligence having fun" Albert Einstein
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clanger9
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Re: Beast and the carb

Post by clanger9 »

Ooh, a cold 8 grade plug might (will?) make it an absolute pig to start.
A hotter 6 grade plug should help get it going, especially on modern fuel.

One trick that works with really reluctant engines is to pre-warm the plug nose with a blowtorch. No need to get carried away, 150 degrees C or so should do the trick.

At least once it's running you have more chance of working out what is wrong... ;)
1989 Moto Morini Dart 350
1993 Ducati 750SS
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clive
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Re: Beast and the carb

Post by clive »

Not surprised at Halfords lack of spark plug range. I thought I would try fitting a new set of plugs to my 14 year old Honda jazz. Couldn't work out where on earth they were. Half the modern cars now are diesil so I guess there are relatively few people changing plugs and professionals are unlikely to pay Halfords prices.

As to the G80 I would recommend champion N5 not a GKN .
clive
if it ain't broke don't fix
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Pharisee
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Re: Beast and the carb

Post by Pharisee »

I've never used an Iridium plug in the M18 but I do use them in my Triumph twins. They both have Pazon ignition systems. They start reliably first kick and don't miss a beat right up to my limit of 6,500 r.p.m.
I'm from the Fens.... Gimme six.
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griffin
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Re: Beast and the carb

Post by griffin »

spookefoote1956 wrote:So this is where I'm at. I've reset the timing and it seems to be trying a lot more. I've checked the carb float with the tube and that's fine. I am however concerned about the Spark Plug. It is one of those fancy NGK BR8IEX Iridium things. I've ordered some BR7ES and BR6ES plugs incase that iridium stuff is too much. It could even be a fake plug as I bought it off fleabay and apparently this can happen. Incidently, I popped into Halfords and was totally shocked by the naff selection of plugs. It's a modern world!
Yes lot of fake plugs on ebay. Try the Green spark plug company http://stores.ebay.co.uk/The-Green-Spark-Plug-Co
Reynard24
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Re: Beast and the carb

Post by Reynard24 »

If you are running a Thorspark ignition are you also using a suppressed plug cap? If you are then both the Iridium plug and the NGK BR series will add to the resistance of the cap as they have integral resistors within them. Some of the older resistive plug caps (Champion in particular) have a resistance of around 10Kohms and I've known a few to go completely open circuit which doesn't help! NGK red caps have a resistance of 5Kohms and the black ones are straight through.
I tried Iridiums in my Commando wth Pazon ignition and it ran like a dog - BP6ES plugs cured it but I know the Enfield boys swear by them for the Indian built Bullets.
StephenG80
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Re: Beast and the carb

Post by StephenG80 »

Which side of the top of mag does your A/R cable go in Spookefoote1956? :?:
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spookefoote1956
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Re: Beast and the carb

Post by spookefoote1956 »

Right N1
Hail Joe Lucas ............ Prince of Darkness!
All my bikes are original........ to me!
"Creativity is your intelligence having fun" Albert Einstein
56G80S
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Re: Beast and the carb

Post by 56G80S »

You could always resort to Bradex Easi-Start!

Or soak the plug in meths and wind it in quick.

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