350 barrel on a G2

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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BultacoBen
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350 barrel on a G2

Post by BultacoBen »

I knew the 250CSR head fitted the 350 barrel, but did not know you could mount the 350 barrel to the 250 bottom as the bike in this ad claims:

http://www.carandclassic.co.uk/car/C832146

I thought the 350 difference was taller barrel (stroke 10mm longer, bore 3mm wider) so is this conversion not just likely to give very low compression?
http://www.ben-eddings.com
1966 Matchless G2 CSR scrambler
1986 Suzuki DR600 long-range explorer
1971 BSA B50T street tracker
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clanger9
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Re: 350 barrel on a G2

Post by clanger9 »

Presumably it's got a 350 crank, rod & piston as well? Fitting just the barrel & head would make no sense...
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Ozmadman
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Re: 350 barrel on a G2

Post by Ozmadman »

clanger9 wrote:Presumably it's got a 350 crank, rod & piston as well? Fitting just the barrel & head would make no sense...
Yes, it would have hardly any compression if not. Plus it is well overpriced even with a grand off it would still be expensive!!
Paul
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ajscomboman
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Re: 350 barrel on a G2

Post by ajscomboman »

Ozmadman wrote:
clanger9 wrote:Presumably it's got a 350 crank, rod & piston as well? Fitting just the barrel & head would make no sense...
Yes, it would have hardly any compression if not. Plus it is well overpriced even with a grand off it would still be expensive!!
It wouldn't have any compression at all, 250's have a 69mm piston 350's use a 72mm.
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Janet
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Re: 350 barrel on a G2

Post by Janet »

ajscomboman wrote:
Ozmadman wrote:
clanger9 wrote:Presumably it's got a 350 crank, rod & piston as well? Fitting just the barrel & head would make no sense...
Yes, it would have hardly any compression if not. Plus it is well overpriced even with a grand off it would still be expensive!!
It wouldn't have any compression at all, 250's have a 69mm piston 350's use a 72mm.
On the bright side, it's unlikely ever to seize in the barrel.
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ajscomboman
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Re: 350 barrel on a G2

Post by ajscomboman »

[quote="Janet" On the bright side, it's unlikely ever to seize in the barrel.[/quote]

:rofl: :rofl:
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Ozmadman
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Re: 350 barrel on a G2

Post by Ozmadman »

ajscomboman wrote:
Ozmadman wrote:
clanger9 wrote:Presumably it's got a 350 crank, rod & piston as well? Fitting just the barrel & head would make no sense...
Yes, it would have hardly any compression if not. Plus it is well overpriced even with a grand off it would still be expensive!!
It wouldn't have any compression at all, 250's have a 69mm piston 350's use a 72mm.
I was presuming that at least they put the 350 piston in!!!
Paul
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1974 Yamaha RD250B US Model 6 speed
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ajscomboman
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Re: 350 barrel on a G2

Post by ajscomboman »

Relax Paul, I was having a laugh. They'd had to have put in a 350 piston, goes without saying really. :)
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