Jampots sticking?

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
AJS_Chris
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Jampots sticking?

Post by AJS_Chris »

Afternoon all,
Relative newby question, sorry!
If I press down hard on the rear end of my '51 Model 18S there is no movement in the jampots until the pressure reaches a certain point then 'clunk' and the jampots compress, suddenly. The action on releasing pressure is similar, nothing then 'clunk' and the suspension suddenly decompresses. I would best describe this as the worst case of stiction I've ever seen. Is what I'm experiencing typical of jampots or is there something to investigate?
Thanks in advance,
Chris.
Mick D
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Re: Jampots sticking?

Post by Mick D »

Hi

It sounds like all of the oil has leaked out and you have some 'stiction' in the sliding components, when this is overcome there is no oil to damp the action and hence the rapid movement.

Full strip down and investigation would be my first step.

Regards Mick
alanengineer
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Re: Jampots sticking?

Post by alanengineer »

Not Normal
Time for a strip down before the sun comes out
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Rob Harknett
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Re: Jampots sticking?

Post by Rob Harknett »

Never had that before of Jampots. How long has the bike been standing? I have never heard of this, but if the bike has been standing has the swinging Arm seized. It may be worth investigating. Much easier to cure than Jampot rebuild.
SPRIDDLER
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Re: Jampots sticking?

Post by SPRIDDLER »

P'raps a Mod can move this from the 'Buyers Guide' section to the Forum or the Buyers Guide will become cluttered with questions..
Buyers Guides
A number of sections used to collate information on the various models in order to produce a "Buyers Guide" leaflet on each model.
Please note these are not discussion areas, please place any discussions/questions in the main Forum area.
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Eamonn
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Re: Jampots sticking?

Post by Eamonn »

Moved
:-)
Corners like a Lego man
Triumph-Legend
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Re: Jampots sticking?

Post by Triumph-Legend »

Easy enough to take the shocks off and remove the springs. I'm betting that the oil has gone walkies and there will be a rough possibly rust ring on the shock moving parts. Be sure to let use all know what you find.

If you don't want to do your own jampot rebuild, don't worry. Just chuck them at John Bolton, (workshop 14). He has the proper tools for the job and loads of experience with these units. He has sorted several sets for me, saves me time and hassle. Not too pricey, nice and quick, good job.
SPRIDDLER
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Re: Jampots sticking?

Post by SPRIDDLER »

Here are two excellent articles on restoring the Jampots if you want to know what's involved or how to do them yourself:


http://archives.jampot.dk/Technical/Sus ... around.pdf


http://archives.jampot.dk/Technical/Sus ... ampots.pdf
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ajscomboman
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Re: Jampots sticking?

Post by ajscomboman »

Or you could use the clubs exchange system and simply swap them.
alanengineer
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Re: Jampots sticking?

Post by alanengineer »

Have you checked the swing arm for smooth action. Do the cheap and simple jobs first
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