Length of an original 1961 G12/Model 31 gudgeon pin?

Information relating to the Matchless G12 or AJS Model 31 650cc twin
Roderick
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Location: WEST YORKSHIRE UK

Length of an original 1961 G12/Model 31 gudgeon pin?

Post by Roderick »

Can anyone tell me the LENGTH of the gudgeon pin from an original Hepolite piston for this model? I don't have one to measure outside an engine.

Rod
alanengineer
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by alanengineer »

About 2 1/2" or do you want it exact
Roderick
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by Roderick »

Exact would be nice, Alan, as I have an engineer who's agreed to make/modify one for me & they do like exact measurement, do engineers. Many's the flea I've in my ear about it!

Best regards,
Rod
ajsph
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by ajsph »

Hepolite: 2.373 inch
Poul
alanengineer
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by alanengineer »

My one seems a few thou longer, but, its in the piston and i have had to do some measuring and some sums
Yves.Astein
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by Yves.Astein »

I am messuring 2.420 inch (61.48 mm) from Hepolite 15036 Article Number.


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Mick D
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by Mick D »

Hi

Surely it's better to measure the piston it's intended to fit - why guess?

Regards Mick
raffles
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by raffles »

If you are going to measure the piston dont forget its the distance less a few thou between the circlip grooves
Tony
Yves.Astein
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Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by Yves.Astein »

Yves.Astein wrote:I am messuring 2.420 inch (61.48 mm) from Hepolite 15036 Article Number.

Just to be clear, above I messured the pin not the piston.
Roderick
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Location: WEST YORKSHIRE UK

Re: Length of an original 1961 G12/Model 31 gudgeon pin?

Post by Roderick »

2.420" looks like the sort of round figure AMC engineers would have used so I am going to take a chance on Yves and "deutsche Teuchtigkeit"! (or is it actually "efficacite francaise", Yves?).

Many thanks Alan, Poul, Mick, Anthony & Yves for taking the trouble to help. Much appreciated.

Rod
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