Crankshaft shock absorber

[Joker_Bones]

I did think after I posted the question... "I hope there's not more than one mistake"

I used whatever studs, bolts, bar stock I had to make up the fixings so they were intentional if not entirely correct.

What was not intentional was this... I built the gearbox from what was advertised as a job lot of spares on ebay, I could see from the photos it was not just random stuff but a complete disassembled gearbox plus extras, so I took a chance on it. Among the extras were three gearbox sprockets, all the same. When it came to it I picked the best one and fitted it.

Months and months later, bike all finished, having a big shed tidy, I put the two unused gearbox sprockets away in a box for such things. In the box there was another old AJS/Matchless gearbox sprocket, but, it was noticeably thicker than these two. Puzzling, so off to the interweb for some reading...

I'd fitted a 1/4" wide Norton sprocket not a 3/8" wide AJS/Matchless sprocket, without realising it. Unwitting mistake or Schoolboy error?

[56G80S]

On the gearbox top mount, Rob is correct, it should be the bolt with the head on the drive side of the machine. I was roundly told off at a rally for having the bolt the wrong way round. I'd been in a rush reassembling .

It was said to me that the nut could come off with the bolt the wrong way round and unpleasantness ensue.

Just a thought.

Johnny B

[Joker_Bones]

The thinking being that in that position if the nut comes adrift it could it jam in the rear chain?

I have a stud in that position... I'll put a spot of sleeve retainer on the thread that that end to stop any chance of it unwinding.

[neil cairns]

Ages ago the spring on my '52 18S shock absorber broke and fell to bits. I found out because the cams DID manage to jump over each other on accelerating and the noise and vibes were a big hint!