Thread and nut pitch

[XT65]

Good afty all hope all's well

chain adjusters Question: [or anything with bolts]

If:

[21 94002-08000-0S NUT, HEX., 8MM •••••••••••••• 2 2 2 2 2 2 2]
[22 94030-08000 NUT, HEX., 8MM ••••••••••••••2 2 2]

And two different pitches are given:

M8 standard = 1.25
M8 fine = 1.00

and if I measure the pitch of the adjuster threads with a pitch gauge and it fits 1.25 better than 1.00 mm

Then does that mean I'd use the fine [bearing in mind one's the lock-nut] so it's a tighter fit , or:
use the standard 1.25 as measured on the adjuster threads?

Is that the convention , [I've never thought about it before]?

Do you find the pitch of something ie a thread and call it the 'standard'
and then use the 'fine' as the nut's internal thread -
or is it simply 'like for like'?

given that - how would I know just from the part description what pitch it is meant to be and nothing to suggest it in the parts info either?

Hope this makes sense -- Maybe .25 of a mm is neither here nor there in the grand scheme of things and as I said ,it's not something I've given any thought to ,tbh .....

If it goes on ,it goes on :)

Cheers all !

[Fat Angry Scotsman]

[steve the grease]

It's not a choice, or about loose and tight threads, it's an either /or choice.. One nut when screwed on the appropriate bolt will move along the thread 1mm if rotated one turn , the other 1.25mm, if you mix the threads the nut will jam on the thread, if you keep turning the nut then it will rip the threads on which ever is the softest material, usually the nut. Most threads are the standard coarse thread ,for 8mm , the 1.25, only special applications use the finer thread.
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All the above is my personal opinion, you can see my lips move, but I'm talking out of my arse.
I've been riding, and fixing , bikes for 50 years, in that time the more I learn, the less I am absolutely sure of.....

[WD Forte]

As said, use the same pitch as the bolt
Mixing them up will strip threads

M8 nuts and bolts usually have a 1.25mm pitch as standard
and 1mm or even 0.75 pitches are regarded as 'fine' thread/pitches
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bikers smell of wee

[MarJay]

[Nobby the Bastard]

It'll go from righty tighty to righty loosey very quickly with a mismatched thread pitch...
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[WD Forte]

You should be able to run a new nut up with finger and thumb
or if it's a lock nut, until it hits the locking collar
if its stiff from the start do NOT use a spanner as you probably have
mismatched threads
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bikers smell of wee

[stinkwheel]

[XT65]

[XT65]

[XT65]

[XT65]

[SpiritMr89]

Thought everyone had a random tub of bolts.

Just find a m8 and try it.

If not go somewhere that has thread bar, and put the bolt against it. If the threads match all the way it is standard.

Knowwing Land Rovers better than bikes these days. Thay have some stuff which is completely custom to them. Could not find the correct thread and pitch anywhere for a 300tdi oil return. 30quid from Land Rover.
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Hello

[Pete.]

I've never yet in my life seen a M8 x 1mm pitch bolt (that I recognised as one).

The odds that it's not 1.25mm pitch are very remote especially for a chain adjuster, there's just no reason for it to be a fine pitch.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Polarbear]

I really would reccomend getting one of these if you are doing your own spannering. Cheap and eliminates any doubts on pitch size. OK, it's not a necessity but I'm a tool nerd and it's nice to have.

https://images-eu.ssl-images-amazon.com/images/I/41RVb1HZRwL._SY445_SX342_QL70_ML2_.jpg

https://www.amazon.co.uk/Deals%E3%80%91OriGlam-Stainless-Measuring-55-Degree-60-Degree/dp/B071H8GP18/ref=sr_1_6?keywords=metric+pitch+measure&qid=1644756896&sr=8-6
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Triumph Trophy Launch Edition

[Kickstart]

[Pete.]

[Kickstart]

[struan80]

UNF and UNC.

[Fisty]