Back wheel lock up

Information relating to the Matchless G9 or AJS Model 20 500cc twin
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john kitchen
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Joined: Tue Dec 10, 2002 12:00 am
Location: PETERBOROUGH UK

Back wheel lock up

Post by john kitchen »

While out on the G9 today my back wheel locked.
The sleeve which adjusts the wheel bearings appears to threaded its self out, spreading the swinging arm apart.

Any suggestion as to why this has happened please?

Thanks

JK
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Biscuit
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Location: KENT UK

Back wheel lock up

Post by Biscuit »

Hi John,

Has the speedo gearbox siezed?



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Colin F
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Back wheel lock up

Post by Colin F »

The common cause of this is misassembly of the rear wheel spacers, one "top hat" which looks like a seal holder should actually be a spacer!
john kitchen
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Joined: Tue Dec 10, 2002 12:00 am
Location: PETERBOROUGH UK

Back wheel lock up

Post by john kitchen »

Colin,
could you give me some more information?
Is the top hat in question the one at the speedo drive end of the axle?
Is the spacer available from the spares scheme?

I have also heard that there is a miss printed exploded drawing of the wheel assembly which makes me wonder if I have done something wrong?
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Biscuit
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Back wheel lock up

Post by Biscuit »

Given the not insubstantial wheel spindle, how has the swinging arm been spread apart?.



Dave
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Location: OXFORDSHIRE UK

Back wheel lock up

Post by Dave »

John,
As Alan suggests, I too would be very surprised if it's not the speedo drive. This is a common problem and I've had it occur on my own bike. As the speedo drive starts to seize the cable stops it turning with the back wheel and as the drive is from the bearing adjusting collar, the whole thing unwinds. It then usually proceeds to chew up the threads for the adjusting collar, thus wrecking the hub. If your lucky it will be just the last couple of threads and you may be able to salvage the hub. The answer is then to rebuild with a 'new' speedo drive. Don't buy one from a jumble as it's probably as knackered as the one that caused the problem.
Also, remember to pump a small quantity of grease into the speedo drive on an annual basis. This, hopefully, will stop a re-occurance of the fault.
Regards,
Dave.

Charles
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Back wheel lock up

Post by Charles »

John,

If it is the speedo drive that has locked up and unscrewed the bearing adjusting collar, there is a way to get this re-engineered by having a new collar made with a left hand thread and re-cutting the thread in the hub. Have a word with Malcolm Saggers who advertises in the jampot as I believe he has done this several times. It cleans up the hub thereby saving you sourcing a replacement and ensures the problem does not happen again or that if it does, you can at least get the wheel out of the swinging arm to free everything up.
Regards
Charles
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Merlin
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Location: BLACKPOOL UK

Back wheel lock up

Post by Merlin »

Sorry to be out of date but been on hols.Silly question I think the problem above is similar to mine will the speedo gearbox listed in the spares list be suitable for my G3LS?[:I]

Chemists do it with test tubes
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