Rear wheel lock up

[56G80S]

A timely warning to us all and pleased that you are OK; there's too few of us to lose people.

It's only recently that I've had a "correct" (I hope) arrangement for this. When I first got the Matchless there was nothing much except tighten up the mounting studs ferociously!

I subsequently fitted a mash up of different parts to stop slippage. While this wasn't standard, it did the trick for 10's of thousands of miles. Currently refitted the AMC box in preference to the Burman and have both the "between the engine plates" device as well as one outside the engine plates on the timing side.

Think I check tightness before next trip out, though.

Johnny B

[fump]

Thank you gentlemen. Yes I must admit to being puzzled as to how i did not note anything wrong. There were two indicators, though without hindsights they appeared insignificant. One was that i missed the gear foot change once which I noted but put down to my wearing brand new boots that day. Another was on descending a steep hill I heard and felt what may have been the secondary chain kind of vibrating, but only once. Both of those could have been indicators that the gear box was loose, but I didn't take the hint.

[cf160]

But, Mr Harknett,Sir, why would that cause the rear axle/wheel to seize ? I drove all over France ,Spain and England with a
loose bearing/rear axel assembly and it never seized in a year's riding . Was I just lucky? Albeit, I kept the chains at proper
tensions all the while...
Dave (cf160)

[Rob Harknett]

I dont see where theres any reference in this thread about a rear axel or rear bearing seizing up David

[fump]

I must admit to being puzzled as to how this happened. I have not yet visited the bike which is still at the repairers, maybe it will become clear when I do..........maybe...I must admit to have fallen out of love with the old bitch.

[en7jos]

Glad to hear your ok Roger. Sure many of us will be on 'are they tight?' duties this weekend now.

James

[TommoT]

Back in the old days, when I had only one adjuster on the gearbox, this used to happen once or twice a year. The primary chain would be yanked string tight by the secondary chain pulling the gearbox backwards. Mostly this happened after longer rides, where the exposure to continued vibrations would losen the nuts. A sure telltale would be a constantly rising whine from the gearbox, but maybe this was in fact caused by worn high gears. However this never failed to alert me. After a few years I fitted two adjusters inside the engine plates, the type that pushes the gearbox forward, preventing the rear chain from pulling the gearbox backwards. Never had an incident after that. Fitted, forgotten and working!

[fump]

Thanks Tommo thats a very good suggestion. I had no idea this was a fairly common problem. I had also no idea this was happening and still find it hard to believe it could so easily become a fatal failure.

[cf160]

My sincere apologies to Mr. Harknett. I really do not know where my post to this topic came from. I must have replied to
the wrong thread and cannot recall which one it might have been.
Sincerely,
David Potter

[Wumpletoad]

Back in the old days, when I had only one adjuster on the gearbox, this used to happen once or twice a year. The primary chain would be yanked string tight by the secondary chain pulling the gearbox backwards. Mostly this happened after longer rides, where the exposure to continued vibrations would losen the nuts. A sure telltale would be a constantly rising whine from the gearbox, but maybe this was in fact caused by worn high gears. However this never failed to alert me. After a few years I fitted two adjusters inside the engine plates, the type that pushes the gearbox forward, preventing the rear chain from pulling the gearbox backwards. Never had an incident after that. Fitted, forgotten and working!

There is another whine, albeit of a different character, emitted by an over-tight primary chain and listening for this is one of the many manifestations of my riding paranoia. There have been a few occasions when the front chain has been "yanked" tight, despite the gearbox being tightly clamped and I have attributed this to deep potholes in the road.

I don't like transmission snatch and have to admit that I used to keep chains a little on the tight side - in the past I've possibly overdone it. Slack in the rear chain will be taken up as a function of rear suspension compression and I suspect that the combination of large potholes and tired dampers has proved too much for the gearbox anchorage. Although I don't like it, I now have the rear chain a little slacker than the book suggests but I've not had to adjust the primary chain in nearly 4,000 miles.