speedo drive gearbox jamming

Information relating to the Matchless G12 or AJS Model 31 650cc twin
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Re: speedo drive gearbox jamming

Post by griffin »

56G80S wrote: Sat Mar 02, 2024 8:09 pm From memory the instruction was to achieve barely perceptible rim rock.

Johnny B
Johnny B .OK thanks for that.
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Re: speedo drive gearbox jamming

Post by Groily »

[quote=griffin post_id=255516 time=1709408420 user_id=94901
As a matter of interest how much play did you give the taper bearings ?
I'd read that you tighten up the adjusting ring then back it off by half a turn which seems excessive to me.
'Back off 1/2 a turn' is what my copy of Neill says too, but when just the other day I was doing the front of my Mod 31 I also had excessive rim rock if I took that literally. So I also settled for 'barely perceptible' .
It's quite a nervous-making area I think, not helped by slight initial stiffness in rotation with new seals fitted which can mislead. Given the cost of complete bearing replacement in the event of error, not something to foul up either!
I had the same experience when I did the rear hub after a speedo g'box disaster - which unscrewed the bearing adjuster almost completely, necessitating a tricky clean-up of the thread in the hub. That end's been OK on 'barely perceptible', so I'm hoping the front will be too.
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