AJS & Matchless Owners Club

After months of unsuccessfully searching for a speedo drive for my AJS 37/22 I decided to make the most of this lock down and try and make one. So with tea in hand it was off to the workshop. I started off by turning a soft alloy mandrel that was just an interference fit with the worm gear, once the gearbox was turned a couple of times it made a nice light indentation in the mandrel so I could count the teeth and the angle of them. I then measured the depth of the teeth on the worm and doubled that and added it to the diameter of the mandrel. I then turned a blank out of Phosphor bronze then carefully hacksawed the teeth into the blank. I then filed the teeth to shape using a thread chaser. I turned a shaft, cut the slot in to it and silver soldered it all together. It's a bit rough, and probably doesn't look like the original but it works.. Wonder how long it will last before it strips the teeth off it? Does anyone know what the originals where made of? Just shows what you can do when have the time.. Hope the lock down is over soon so I can go out and test it.

Keep Safe Everyone

It fixes my boredom just marvelling at your skills with metal, AJS; keep us updated when you eventually try it.

You have not mentioned " hardening " which they should be.

Hi Rob

Hope you are well?

It was hardened after silver soldering and then slightly tempered as if you harden it too much the teeth will just sheer off...

I had 20 gears made for the model H box a few years ago by a local company that makes gears for as long as I can remember. No complaints except from one person , after a while he claimed he did not receive the gear, I sent another , he claimed it was not hardened. Turned out, he was putting it in a box that was not a Mod H. I have tried to scan what the Mod H gear looks like

very impressive, even contemplating taking on a job like that deserves praise, well done

Colin

Just an update. Bikes done over 800 miles now and the speedo drive still looks good as new