AJS & Matchless Owners Club

Morning all, another day in the workshop whilst the head is getting sorted!

So silly question time! I believe this item has been fitted incorrectly, but what does it do? I can't find a reference to it in the workshop manual, possibly because I don't know what its function is or maybe its not referenced and I'm hesitant in just whipping it off without knowing the implications first.

All replies welcomed as it's the only way to learn, visual reference work best and many thanks

http://archives.jampot.dk/book/Owners_m ... ingles.pdf

See page 41 of this (I hope representative) manual which illustrates the Burman gearbox.
It's the primary chain tension adjuster that locks the gearbox in position and provides adjustment. The 'box pivots at the bottom. The description in the text in the link says it better than I can!

It's like this on my my '54 G3LS which is correct (but tatty) ....

That looks better Spriddler and will operate as an adjuster for the Primary chain much better as it in the line the gearbox needs to move. Paul the adjuster ought to be threaded and so act as the nut on the stud. It does look as though your gearbox is at the end of its adjustment suggestion that the primary chain may be at the end of its life or too long. According to the parts list, and assuming you have an 18 tooth front sprocket the primary chain should be 66 links. I wonder if you may have a 67 link one which is for the 500 which has a bigger front sprocket.

Guys, thank you all for the quick replies and much appreciated advice and guidance to it's function.

Spriddler thanks for uploading some photos, they came at just the right time as my initial photo and thoughts on placement of the adjuster would have been incorrect. It should look like this:
Clive, TBH I'm not sure! I've got the upgraded seal to fit so seems the best time to go and check my teeth and links

I'm guessing that the adjuster has been like this since having a 1956 engine replacement beforec I acquired it. However, compared to Spriddlers bolt the one on mine does look on the long side.

clive wrote: ↑Tue Jan 24, 2023 12:09 pm According to the parts list, and assuming you have an 18 tooth front sprocket the primary chain should be 66 links. I wonder if you may have a 67 link one which is for the 500 which has a bigger front sprocket.

Clive, I've just checked and it's a 20 tooth front sprocket with a 67 primary chain! So would that mean it's been changed for more top end speed?

Paul

PX207 wrote: ↑Tue Jan 24, 2023 3:02 pm

clive wrote: ↑Tue Jan 24, 2023 12:09 pm According to the parts list, and assuming you have an 18 tooth front sprocket the primary chain should be 66 links. I wonder if you may have a 67 link one which is for the 500 which has a bigger front sprocket.

Clive, I've just checked and it's a 20 tooth front sprocket with a 67 primary chain! So would that mean it's been changed for more top end speed?

Paul

20 tooth sprocket would allow a higher cruising speed, at the cost of acceleration and power up hills. I think you will have to stick with the 67 links, but I wonder how worn it all is, sprockets, clutch basket and chain. I would try turning the adjuster round to the stud and see if it fits. You will definitely need the nuts on both sides of the adjuster to enable the locking to work properly.

Cheers Clive I'll give it ago tomorrow

Neville, thanks for these photos! I've got the B52 in the frame now but it's so long ago that I took it out I couldn't remember how the adjuster fitted!

My top gearbox stud may be too short, but that's easily fixable.

Johnny B