Missing spring on Auto Advance/retard

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
Andy51
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Location: BERKS UK

Re: Missing spring on Auto Advance/retard

Post by Andy51 »

Hi All, and thanks for your help. I have freed up the ATD using WD40 and elbow grease (rust in the pivot where the main moving assembly fits on the backplate/sprocket - there is a tube/spigot as part of the body, and the moving assembly has a tube that fits over it), but how to keep it free? I can lubricate the external parts, eg bobweights, with engine oil/grease, but the main pivot is close-fitting and has press-fit rings top and bottom with only a few thou clearance, making it hard to get oil in. I suspect that engine oil may not penetrate properly, but penetrating oil, eg plusgas, will be too thin and may well dry out in time. What is the best way to lubricate this pivot? Thanks, Andy
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Rob Harknett
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Location: ESSEX UK

Re: Missing spring on Auto Advance/retard

Post by Rob Harknett »

Andy51 wrote:Hi All, and thanks for your help. I have freed up the ATD using WD40 and elbow grease (rust in the pivot where the main moving assembly fits on the backplate/sprocket - there is a tube/spigot as part of the body, and the moving assembly has a tube that fits over it), but how to keep it free? I can lubricate the external parts, eg bobweights, with engine oil/grease, but the main pivot is close-fitting and has press-fit rings top and bottom with only a few thou clearance, making it hard to get oil in. I suspect that engine oil may not penetrate properly, but penetrating oil, eg plusgas, will be too thin and may well dry out in time. What is the best way to lubricate this pivot? Thanks, Andy
The chain is greased. The A/R unit may often seize. In particular if not used often. I seldom had an AR seize in the 50's when I used the bike every day. They may seize over winter if not used. You just need to keep them cleaned out. As I said, if the bike gets difficult to start and back fires, it probably seizing up.
raffles
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Location: NORTHAMPTONSHIRE UK

Re: Missing spring on Auto Advance/retard

Post by raffles »

Andy
springs on their way. I pack the chain case with graphite grease. have run the same bike for 39 years no AVR problems
Tony
Andy51
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Location: BERKS UK

Re: Missing spring on Auto Advance/retard

Post by Andy51 »

Thanks Tony
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cfaber
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Re: Missing spring on Auto Advance/retard

Post by cfaber »

raffles wrote:Andy
springs on their way. I pack the chain case with graphite grease. have run the same bike for 39 years no AVR problems
Tony
what do you seal it with?
Fix it until it's broken!

Otherwise how will
anything get done?
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dave16mct
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Location: LANCASHIRE UK

Re: Missing spring on Auto Advance/retard

Post by dave16mct »

It doesn't need sealing, just assemble dry. There's no pressure in there and no grease will leak out.
Dave.
raffles
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Location: NORTHAMPTONSHIRE UK

Re: Missing spring on Auto Advance/retard

Post by raffles »

I cant remember the part number but I use the big thick rubber that I think fits over the end of the manual advance mag
I do have to slightly reduce its thickness fit it between the mag and the back of the timing case. No water in no grease out
hope this makes sense
Tony
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