Rear chain adjuster screw thread size

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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Richard Hyatt
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Rear chain adjuster screw thread size

Post by Richard Hyatt »

Good morning,
Does anyone know the thread size of the rear chain adjusters please.
My adjusters are so chewed that I can't put a thread gauge on them to check.
I'm guessing at BSF or cycle threads.
Thank you.
cbranni
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Re: Rear chain adjuster screw thread size

Post by cbranni »

1/4" cycle I believe.

Colin
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Mick D
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Re: Rear chain adjuster screw thread size

Post by Mick D »

Hi

If they're the same as those fitted to a HW they have a reduced hex head.

Regards Mick
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Martin.S
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Re: Rear chain adjuster screw thread size

Post by Martin.S »

If I'm not wrong - every thing on these bikes are Cycle unless it's screwing into aluminium and then it's BSF - this excludes the tiny little BA screws.
Cheers
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Rob Harknett
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Re: Rear chain adjuster screw thread size

Post by Rob Harknett »

Once again I repeat the, how you could find a fitting size procedure. As most fittings have been used since prewar / pre 1952 era, when parts lists also gave many sizes in description, many sizes not being given in post 52 parts lists. Check to see if the part number converts to an old part number. Now lets see, G2 chain adjuster has a nut 000290. Strait away I see that as old pt. no. STD 290. You can check by going to the new/old parts list conversion book. I put it top of the list in the archives, so easy to find. http://archives.jampot.dk/book/Spares_l ... ements.pdf
Here you will see 000290 or STD290 (old pt. no. ) is 1/4" 26 TPI. So the adjuster must also have 1/4" x 26 TPI thread. Easy to discover yourself. A lot quicker than asking some one else to do it for you. You also see for yourself, the correct size.
Richard Hyatt
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Re: Rear chain adjuster screw thread size

Post by Richard Hyatt »

Thank you all for that , normally I'm ok with threads etc, but I hadn't found the link in the last reply , now I know where to look.
The big problem is , as you probably know , is having the part number to start with as these lightweights - everyone tells me -were a bit short on drawings and part numbers I usually do as much research as possible as I like to know and learn , but sometimes just get stuck. Hence the request.
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Martin.S
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Re: Rear chain adjuster screw thread size

Post by Martin.S »

Try a 1/4" cycle bolt in the swinging arm lug.
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Rob Harknett
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Re: Rear chain adjuster screw thread size

Post by Rob Harknett »

Richard Hyatt wrote:Thank you all for that , normally I'm ok with threads etc, but I hadn't found the link in the last reply , now I know where to look.
The big problem is , as you probably know , is having the part number to start with as these lightweights - everyone tells me -were a bit short on drawings and part numbers I usually do as much research as possible as I like to know and learn , but sometimes just get stuck. Hence the request.
Later Parts list's including lightweights, were short of parts illustration's. So check the bikes instruction manual, in conjunction with the parts list, where you will find exploded views etc. of parts. Still not as good as the old illustrated parts lists. But the instruction book illustrations help a little. For AMC James, you may find all illustrations of parts, are in the instruction books. After about 1960 you got many supplements of parts that differ. These do state on the cover to use perhaps, the 1960 parts list in conjunction with the later supliment.
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Rob Harknett
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Re: Rear chain adjuster screw thread size

Post by Rob Harknett »

SPRIDDLER
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Re: Rear chain adjuster screw thread size

Post by SPRIDDLER »

Richard Hyatt wrote:...I usually do as much research as possible as I like to know and learn , but sometimes just get stuck. Hence the request.
Exactly.

As the man said:

'There are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns — the ones we don't know we don't know'.

And that's where this Forum can help ;)
'There is a tide in the affairs of men
Which taken at the flood............'
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