Camshafts

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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Numnuts
Posts: 2
Joined: Tue May 29, 2018 10:33 am
Location: SW Scotland

Camshafts

Post by Numnuts »

Hi Folks,
I'm a newbie to all this brit bike shebang.
I've just bought a basket case, two frames a 1952 G80 and a 1957 18S with most of a 1952 G80S engine.
As far as I can tell the only major bits missing appear to be the cams. I've seen a few on ebay that just say Matchless or AJS cams without being specific about the model or year.
My question is there much difference between cams for 350 and 500 , heavy weight/lightweight or is it one size fits all.
Also are cams ok to be reground as most for sale appear to have some pitting.
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dave16mct
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Posts: 3234
Joined: Mon Jan 01, 1990 12:00 am
Location: LANCASHIRE UK

Re: Camshafts

Post by dave16mct »

Hi Andy, welcome to the forum. Sounds like a good project. I would go for the 52 G80S. Is it a swinging arm frame? I would look for 'H' cams. They are slightly later than 52 and can easily be identified by the H on the cam and numbers 1, 2 and 3 on the wheels. They are a good allround cam for good performance but not too lumpy. Don't know about grinding them, you may need to re-harden. One thing you should do is join the club. Loads of help, spares, spares scheme, magazine and club activities etc. There's a lively Scottish section,(they're probably on their way back from Portugal at the moment!) :D
Cheers Dave.
SPRIDDLER
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Posts: 8542
Joined: Wed Sep 01, 2004 1:00 am
Location: WEST SUSSEX UK

Re: Camshafts

Post by SPRIDDLER »

Welcome, Andy. And join the club!
What Dave said, plus...........

There's masses of techy and other info in Christians Archive. Have a browse:

http://archives.jampot.dk/

This article on cams (there are several others) from Christians Archive may be of use/interest:

http://archives.jampot.dk/technical/Gen ... e_Dots.pdf
'There is a tide in the affairs of men
Which taken at the flood............'
Numnuts
Posts: 2
Joined: Tue May 29, 2018 10:33 am
Location: SW Scotland

Re: Camshafts

Post by Numnuts »

Thanks for the info.
I'll have a search, I'm in no rush, there's a couple of other projects to complete / put out of their misery before I start on this one.
Off at a tangent, the G80 frame has the tank fixing lugs cut off, is this common practice to use a different tank or just someone with a 'unique' plan.
Cheers
P.S. Joined the club last week.
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dave16mct
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Posts: 3234
Joined: Mon Jan 01, 1990 12:00 am
Location: LANCASHIRE UK

Re: Camshafts

Post by dave16mct »

That's a shame about the tank lugs especially if you're going to rebuild to standard. If you've a special or trials/CS spec in mind, you could fit an alloy tank from a different make, or make front lugs and fit an AMC alloy tank with hooks for a rubber belt at the rear. It's good you've joined the club, you'll find a lot of benefits.
Dave.
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