1951 AJS 16MC Rigid gas tank

Information relating to the Matchless G85 500cc Heavyweight, AJS 7R, Matchless G45 and Matchless G50
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Matchymarty
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Location: AUSTRALIA

1951 AJS 16MC Rigid gas tank

Post by Matchymarty »

Hi all,

A friend has been converted to 'real bikes' and has purchased a 16MC, but I won't hold it against him for not getting a Matchless. hehehe.

He is searching for a correct petrol tank and Oil tank.
Does anyone know what it should look like? The frame has mounting points the same as my '55 G80CS for the 4 post Petrol tank. Is it the same tank? Or does the '51 have a cutout like the touring tank?

Also, is the oil tank supposed to be the same as say, a '49 G80S ?(just using that as a comparison)

Cheers for any help.
Marty
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dave16mct
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Location: LANCASHIRE UK

Re: 1951 AJS 16MC Rigid gas tank

Post by dave16mct »

It isn't like your '55 alloy tank. It's steel, smaller than the road tank. It sits on alloy bobbins at the front (drawings with sizes in the tech section). At the back it has fixed brackets to fit the tank mountings. Cap is the standard bayonet type. There are 2 types, rigid and springer. The springer has a cutaway for the seat nose. The rigid has no cutaway.
Not too sure of the oiltank but the cap doesn't come out on an angle, it sits straight, more tucked in. At the back it's cutaway for the bigger tyre and the breather pipe is high up.
Cheers Dave.
Matchymarty
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Re: 1951 AJS 16MC Rigid gas tank

Post by Matchymarty »

My '55 G80CS has the narrow steel tank. Didn't know any of them came with alloy tanks from the factory?

In any case, thanks for the info - Can't quite find what you are referring to in the tech section. Is there any photos of a correct tank?

Cheers.
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ajscomboman
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Location: HAMPSHIRE UK

Re: 1951 AJS 16MC Rigid gas tank

Post by ajscomboman »

If you scan through the photos section from the main club home page, click main directory and then competition machines. Click on page 3 to see pictures of the rigid trials tanks and then on page 5 scroll down to G3LC/S where you'll see the oil tank and the fuel tank on the wife's bike which shows the spacer arrangement.
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dave16mct
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Joined: Mon Jan 01, 1990 12:00 am
Location: LANCASHIRE UK

Re: 1951 AJS 16MC Rigid gas tank

Post by dave16mct »

It's in Christian's achives, here:

http://archives.jampot.dk/technical/Do- ... system.pdf

Also, in the pics section, comp bikes, bottom of page 3 there are 2 good pics of the steel comp tank.

Dave.
39speedtwin
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Re: 1951 AJS 16MC Rigid gas tank

Post by 39speedtwin »

Marty,
I have sent you a PM
Regards Dudley
Triumph-Legend
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Re: 1951 AJS 16MC Rigid gas tank

Post by Triumph-Legend »

Having seen two of these comp tanks damaged by the fitting of either incorrect spacers or longer than standard bolts, I thought that I would sort out a fool proof fixing of the front support pillars that would avoid the risk of damage and puncture of the tank. The solution is simple. I produced a copy of the alloy front mounting pillars, but instead of drilling clean through, I drilled and tapped each end 5/16 - 26tpi. A short stud thread locked into one end of each pillar locates into the two plates on the front under side of the tank. then a shorter than standard bolts are used for the lower mounting with the standard spacers and rubber washers. This simple modification is looks in every respect identical to the original fitment, but ensures that the tank can never be damaged by the bolt puncturing the under side of the tank.

If you have a similar tank, do be very careful when fitting the front mounts. If the tank is damaged by the fixing bolt, it is a bloody pest of a job to fix, requiring the plates welded under the tank to be cut off, the tank repaired and new plates / plates made up and welded back into place. Yes it is possible, but far better to either be extra careful when fitting or to use modified parts to avoid the problem. Somebody is bound to notice that the rear mounting bolts are fitted with the nut on the top side. This is quite deliberate, Not wanting to use modern Nylock nuts I cheat and use thread lock on the threads and having the nut on top allows easy checking that nothing is coming loose. Again, simple but effective.

Ps, The early tanks are such a good looking tank, it's no wonder they are sought after.
Tank-1.JPG
Matchless on the Fotheringhay.jpg
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