Running rich

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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bazajay
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Posts: 29
Joined: Wed Dec 04, 2013 7:42 am
Location: SWITZERLAND

Running rich

Post by bazajay »

Hi All
I‘m just running in my 49 18s (done 700km now) but I am having a problem with it running rich.It‘s got a new pre mono carb from Amal on so jets etc are all standard for 18S (I have found Amal pretty good supplying the correct carb for whatever bike is specified). It was running rich so I tried the the first step, dropping the needle, it‘s now on the deepest setting. Still rich, my biking mates pointed me towards float height (which I would also do on any other carb) well its not easy on a pre mono. After much research I found out about washers under the banjo connection to drop the whole reservoir. Done that but still running rich!
Do I really start looking at the cutaway?? Or changing jets?
Bike running okay seems to lack a bit of power but don‘t count on that as it my first classic. Also getting a bit of popping on overrun when hot (exhaust is a good fit and there is no air leak on the intake side).
The plug defiantly screams at me RICH, really black etc.

Any thoughts on pre monos would be really appreciated as apart from that she is wonderful! Really appreciated here in Switzerland, constantly being asked about her wherever I take her - she is beautiful and I am in Love (don‘t tell the wife!)
Cheers Barry
Zen and the Art of Motorcycle Maintenance -Logic is like a bulldozer, it is slow but it will get you through any problem!
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griffin
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Joined: Thu Jan 01, 1998 12:00 am
Location: NOTTINGHAMSHIRE UK

Re: Running rich

Post by griffin »

Just a thought Baz but what plug are you using and is it a genuine one. I once had trouble with what I thought was rich running but turned out to be an NGK copy plug.
eBay is awash with cheap copy's.
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bazajay
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Joined: Wed Dec 04, 2013 7:42 am
Location: SWITZERLAND

Re: Running rich

Post by bazajay »

Thanks Griffin the plug is from the club so I would hope it is genuine!
Zen and the Art of Motorcycle Maintenance -Logic is like a bulldozer, it is slow but it will get you through any problem!
56G80S
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Location: N YORKS UK

Re: Running rich

Post by 56G80S »

I know nowt but is the air filter fitted and is it clear?

What happens if you remove it?

Johnny B
MalcW
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Location: DEVON UK

Re: Running rich

Post by MalcW »

Just a thought since you're in Switzerland, but you're not riding round at higher altitudes and thinner air by any chance?

Malc
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bazajay
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Joined: Wed Dec 04, 2013 7:42 am
Location: SWITZERLAND

Re: Running rich

Post by bazajay »

Thanks for the feedback, there is no air filter and I dont live in the mountains
Cheers
Zen and the Art of Motorcycle Maintenance -Logic is like a bulldozer, it is slow but it will get you through any problem!
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