Re: Matchless 350 G5 piston and rings.

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
Andy1730
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Re: Matchless 350 G5 piston and rings.

Post by Andy1730 »

Hi all ..I am building a 350 G5 from a box full of bits I bought off eBay..I am looking for a standard piston and rings ..the barrel has been bored out quite a few times and I've been told it's better to have it sleeved and bored back to standard...I've had a look round on a few sites but had no luck in finding one can anyone help..Many thanks. Andy.
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clanger9
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Re: Re: Matchless 350 G5 piston and rings.

Post by clanger9 »

Some good info in this thread:
http://www.jampot.com/forum/viewtopic.php?t=15584

Apparently a 1959 (only) 650 twin piston will fit...
1989 Moto Morini Dart 350
1993 Ducati 750SS
Rangy65
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Re: Matchless 350 G5 piston and rings.

Post by Rangy65 »

Try J W Thornton https://www.fwthornton.co.uk/15151-std- ... l-8-295352

They have the models mixed up between Matchless & AJS but a G5 & Model 8 are the same.

I always use Australian JP pistons in my G5's built four now and all are running fine ( with different owners).
G5orModel8piston.png
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Rangy65
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Re: Matchless 350 G5 piston and rings.

Post by Rangy65 »

Apparently a 1959 (only) 650 twin piston will fit...
Sorry but this is not correct. The 59 650 twins have a domed piston which just will not work in a 350 lightweight G5 or Model 8

See photo below which is self explanatory. Lightweight on the left, Twin on the right.
G5vModel31Piston.jpg
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ajscomboman
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Re: Matchless 350 G5 piston and rings.

Post by ajscomboman »

Rangy65 wrote:
Apparently a 1959 (only) 650 twin piston will fit...
Sorry but this is not correct. The 59 650 twins have a domed piston which just will not work in a 350 lightweight G5 or Model 8

See photo below which is self explanatory. Lightweight on the left, Twin on the right.
G5vModel31Piston.jpg

Sorry Steve but you're wrong as I actually wrote the info. A 59 twin piston does fit and raises the comp quite nicely. I know as I modified the skirt to clear the flywheels and ran it for years, very nippy it was too as my section will testify.
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les ward
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Re: Matchless 350 G5 piston and rings.

Post by les ward »

I remember Rob doing this and it certainly was a nippy bike, which accelerated better than the heavyweight 350s. I think I saw it a Jampot rally a few years back with its new owner, who seemed pleased with it.
Rangy65
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Re: Matchless 350 G5 piston and rings.

Post by Rangy65 »

No problem Rob but it has to be modified its not a direct replacement.
G15 Roy
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Re: Matchless 350 G5 piston and rings.

Post by G15 Roy »

les ward wrote:I remember Rob doing this and it certainly was a nippy bike, which accelerated better than the heavyweight 350s. I think I saw it a Jampot rally a few years back with its new owner, who seemed pleased with it.
Quite right Les that would have been Alan Earl sadly no longer with us but the bike is, and currently for sale on our web site may be Mr Swift may like to buy it back?
Roy
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Re: Matchless 350 G5 piston and rings.

Post by shifter »

And the little 350 lightweight in question that was for sale is spot on
Last edited by shifter on Thu Sep 17, 2020 7:41 am, edited 2 times in total.
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ajscomboman
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Re: Matchless 350 G5 piston and rings.

Post by ajscomboman »

G15 Roy wrote:
les ward wrote:I remember Rob doing this and it certainly was a nippy bike, which accelerated better than the heavyweight 350s. I think I saw it a Jampot rally a few years back with its new owner, who seemed pleased with it.
Quite right Les that would have been Alan Earl sadly no longer with us but the bike is, and currently for sale on our web site may be Mr Swift may like to buy it back?
That's not my L/W Mr B.
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