Slider for TLS query. 1972 750 Commando

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NoLongerHere

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I have a possible issue I'd like to resolve.
I was told that my fork slider didn't look right, I forget who told me now, and that the anchor for the brake shoe should not have a big gap between them like mine has. Directly compared to a brand new AN slider my slider is the same.
Have a look at the picture to see what I mean, (ignore the ally spacer that I placed there to fill the gap).
The slider is fully home against the brake plate at the spindle housing.
I'd appreciate any ideas as to what could be wrong or different.

BTW, it's been like that for as long as I have owned it, nearly 5 years.
20201224_092856.jpg
 

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I would be looking into the changes Norton put in place for the change to the 7 3/8" wide yokes over the 7", the RGM writeup confirms the axle boss was modified but does not refer to any changes to the brakeplate boss. Maybe Norton did not bother, BSA/Triumph made the same error in 68/69 when they introduced their wider spaced yokes and only the 70 onwards had a deeper boss that gives full engagement with the brakeplate slot.
 
RGM has 2 part numbers for the Torque stop pivot.

063274 and 060004, note 063274S is the stainless version of 063274

Worth looking on AN for any usage details.
 
RGM has 2 part numbers for the Torque stop pivot.

063274 and 060004, note 063274S is the stainless version of 063274

Worth looking on AN for any usage details.
The thing is I don't think a longer torque pin will make any difference as the engagement length in the slider seems ok. It seems to me the boss is short. Maybe if I was to just put the ally washer against the boss and the nut on top?
 
Is the wheel in the centre of the forks?
Is the brake plate the correct one, IE are there any differences throughout the range regarding the spindle boss part of the brake plate?
 
"x2 43"

"Quantity required: 2
"
 
For comparison, here is the TLS on my Atlas, 7 3/8”, compared to the SLS on my ‘62 ES2, with 7” wide forks. The edge of the brake anchor lug is even with the axle flange on each style, no extra spacers required. The axle flange and lug are 3/16” wider on the Atlas slider to compensate for the wider stance. The TLS can be used in place of the SLS brake plate without any modifixations.
Slider for TLS query. 1972 750 Commando

Slider for TLS query. 1972 750 Commando
 
It looks to me as though the alloy of the brake anchor boss in the original post has been cut down, as it's not at all as tall as the one in Interbak's picture. No idea why someone would have done that though, unless they were trying to fit it into a set of forks with 7" yokes, but 7 1/4" sliders (and even then I can't see how it would help).

In regard to Kommando's comment about Triumph sliders, the 69 slider had a taller boss for the brake stay (and a different part number than the earlier slider), so it did fully engage. The 70 model slider changed things again and used a rectangular welded platform. I'm not an anal retentive about Triumph forks - I'm just assembling six sets at the moment for a number of 60s Bonnies I'm building and there are lots of small differences year to year that need to be correctly matched to avoid dramas with assembly.
 
The two fork legs shown by Interback are different. It does kinda look like Cabs leg is the same as the TLS one in Interbacos pic but perhaps cut down as bsaboss says.

I can’t see it being any issue though. As Kommando says, a deeper nut should keep the comments away.

BTW is it only me who raises an eyebrow at Norton’s engineering here, having a sharp steel thread butt up hard against soft alloy?

Zoomed in pics:

Interbakcs SLS:
Slider for TLS query. 1972 750 Commando


Interbacks TLS:
Slider for TLS query. 1972 750 Commando


Cabs (the OP) TLS:
Slider for TLS query. 1972 750 Commando
 
"x2 43"

"Quantity required: 2
"
Crikey, so it's simply a case of a locknut being missing!
 
The two fork legs shown by Interback are different. It does kinda look like Cabs leg is the same as the TLS one in Interbacos pic but perhaps cut down as bsaboss says.

I can’t see it being any issue though. As Kommando says, a deeper nut should keep the comments away.

BTW is it only me who raises an eyebrow at Norton’s engineering here, having a sharp steel thread butt up hard against soft alloy?

Zoomed in pics:

Interbakcs SLS:
View attachment 20605

Interbacks TLS:
View attachment 20606

Cabs (the OP) TLS:
View attachment 20607
No it's not the thread against soft alloy , the anchor stud is machined flat where makes contact
 
Thanks for your replies. If it's a simple case of a half nut being missing (LAB's post) then easy peasy. I had a look at the 2LS (one of Don Penders) on my Domi-natrix as a reference and no extra lock nut there. I had the slider modified for that though to use it on 7 inch spaced forks.
Slider for TLS query. 1972 750 Commando
 
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Crikey, so it's simply a case of a locknut being missing!

I don't know, or if a second nut is necessary or if the factory ever fitted that second nut. It seems likely they didn't but that's the quantity given in the '1972' and '1973' parts books!

The '68-'70 book says...1 nut.
The '71 book has the nut and pin drawn on the diagram but both are missing from the list!
 
Seems to me you have 2 correct diagnosis above.

Take the spacer off
Take the nut off
put spacer on first
put nut back on

someone cut/modified the torque boss down. The aluminum spacer attempts to restore the bad mod.

Ho Ho Ho Merry Christmas
 
Take the spacer off
Take the nut off
put spacer on first
put the nut back on (with loctite).

That was one option I thought of before LAB pointed out there are two nuts listed in the parts drawing.

Happy Christmas too.
 
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Swapping the spacer will still leave you exposed to remarks from rivet counters! Deeper nut will fool all but the most annoying...
 
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