Author Topic: 3 speed box, is the sprocket nut left or right hand thread  (Read 1077 times)

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Online Donald

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3 speed box, is the sprocket nut left or right hand thread
« on: February 28, 2018, 05:26:42 pm »
Hi all,
my question for the day is , 3 speed box, is the sprocket nut left or right hand thread,

Donald

Online camman3

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #1 on: February 28, 2018, 05:53:53 pm »
Logically, it would be right hand thread :-\....but wait for confirmation.
Graham
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Online Cosmikdebriis

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #2 on: March 01, 2018, 06:52:43 am »
Didn't BSA stamp "LH" on their nuts :-X
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Online camman3

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #3 on: March 01, 2018, 09:12:13 am »
Ouch!!.....its got to be RH surely?...somebody must have one on the bench and know for certain :-\
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Online Tman

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #4 on: March 01, 2018, 09:29:26 am »
My heavy-weight four speed was definitely an RH thread. It would tend to loosen in use if it was LH.

Offline allen brighton

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #5 on: March 01, 2018, 10:43:38 am »
hi
on my c10l, that has a three speed box the thread is standard right hand that's assuming that the sprocket nut is the "c" nut [ no flats ]  as a point of reference the myford c spanner fits a treat

the other nuts that retain the clutch one is lh one is rh [marked]

regards

allen

Offline timsdad

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #6 on: March 01, 2018, 10:52:12 am »
Yes, definitely standard, right-hand thread. I've just looked at one in the shed but it has an ordinary, thin hex nut on it to secure the sprocket.

Ray
Just a motorcyclist.

Online Donald

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #7 on: March 01, 2018, 12:16:46 pm »
Thanks everyone  , it's being problematic, WD not working , it's up to the blowtorch now.

Online Cosmikdebriis

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #8 on: March 01, 2018, 01:11:39 pm »
So... As a point of interest, was I right in assuming BSA stamped "LH" on their nuts where appropriate?
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Online Owen

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #9 on: March 01, 2018, 02:54:02 pm »
Can't say I've seen LH. I know some have a small Nick in the hex outer edge to denote LH thread.
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Online Tman

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #10 on: March 01, 2018, 05:56:21 pm »
BSA stamped the hub bearing retainers "LH"

Online Donald

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #11 on: March 01, 2018, 07:19:19 pm »
Thanks everyone,
    Its a normal right hand thread,took some doing to get it off ,
an old box completely seized up selector forks on shaft,rusted solid,
anybody got a serviceable gearbox sleeve gear 29-3825 and a main shaft 29-3781 (splined) 

Offline timsdad

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Re: 3 speed box, is the sprocket nut left or right hand thread
« Reply #12 on: March 01, 2018, 08:41:42 pm »
There are different ways of marking left hand threads, LH or little circles, but often no marks at all.

I've just got a feel for them now and, if I haven't got an instruction book handy, I'll use a power tool if possible and try it first the most likely way for half a second and then the other. This works for me and it's a very long time since I've messed up a thread.

Mostly, you can tell by just looking at it closely and, perhaps, a thumb nail.


Ray
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