Cylinder head removal

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
Steve S
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Location: Hertfordshire United Kingdom

Re: Cylinder head removal

Post by Steve S »

I have the correct head stay bracket and the extended rocker box studs, but of course the stay is no use to me. I now also have a pair of 350 NOS rear shocks which I can't use!

Maybe I'll get round to making up a shorter bracket when I come to re-torque the head later on. Does a head stay make much difference to a lightweight?

Steve S.
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clanger9
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Location: Chester, UK

Re: Cylinder head removal

Post by clanger9 »

I think it reduces vibration and frame flex a bit.
Mine felt better after I fitted one, but there are plenty of Lightweights happily running about without a head steady...

PS: if you have a set of NOS rear shocks then you are very lucky! They are super-rare...
1989 Moto Morini Dart 350
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Rangy65
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Re: Cylinder head removal

Post by Rangy65 »

Hi Have you thought about finding a G5 frame as that will cure your issues?

Cheers

Steve
Steve S
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Re: Cylinder head removal

Post by Steve S »

Yes I'll keep an eye out for one, are the rear section and swinging arm different?

Or maybe finding a 250 motor might be easier!

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Janet
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Re: Cylinder head removal

Post by Janet »

Steve S wrote:Yes I'll keep an eye out for one, are the rear section and swinging arm different?
I don't know because I don't have a 350, but I suspect there may be differences because the 250 has 17" rims and the 350 has 18". THe parts lists would show if there is a difference.
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ajscomboman
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Re: Cylinder head removal

Post by ajscomboman »

Rear frame is the same, the difference is in the length of the rear shocks to accommodate the 18"rims on the 350. It'd probably be easier to source the correct 250 parts rather than the 350 frame. I know a man with 250 CSR cases that you could insert the internals into once you have found a rod, barrel and piston. ;)
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ajscomboman
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Re: Cylinder head removal

Post by ajscomboman »

ajscomboman wrote:Rear frame is the same, the difference is in the length of the rear shocks to accommodate the 18"rims on the 350. It'd probably be easier to source the correct 250 parts rather than the 350 frame. I know a man with 250 CSR cases that you could insert the internals into once you have found a rod, barrel and piston. ;)
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Martin.S
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Re: Cylinder head removal

Post by Martin.S »

PS: if you have a set of NOS rear shocks then you are very lucky! They are super-rare...
Are they? -I just bought some off of Ebay!
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Martin.S
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Re: Cylinder head removal

Post by Martin.S »

It'll probably be cheaper to swap the frame. The cost of a good crank and rod, barrel and piston, pushrods? gasket set, exhaust pipe, come to mind. But then of course it then depends whether you have/want 18" wheel rims and whether the mudguards really do need to be changed - I cant imagine they do.
I suppose really you'd need to sit down and go through the parts list to make an opinion on what has to be changed and would it really be worth it - after all - how often do you want to take the head off?
Steve S
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Joined: Fri Sep 30, 2016 12:03 pm
Location: Hertfordshire United Kingdom

Re: Cylinder head removal

Post by Steve S »

Yes I agree it would be expensive and to what aim, as I'm not after originality; the bike seems to fit together ok as it is and I can get the head off now I know how to do it!

I do wonder how it came to have the smaller frame though as the wheels are 18 inch and it has the 350 forks.

Also, I have never found the frame number, I know where it should be but there is nothing!

The log book and previous MOT lists it as 8286 with engine number 60/8/1483 although the actual number is 60/8/799!

Here's a pic.

Steve S.
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