Apologies for the delay replying ...
To clarify confusion introduced in later posts:-Axles
Not "TLS" or "SLS", they depend only on the distance between fork-leg centres and the sliders/axle caps.
The axle used on '68 6-1/2" forks irrespective of hub/drum or brake is W1641, it was introduced in '65 with changed sliders and axle caps. The preceding W1239 axle is also for 6-1/2" forks and also fits the hubs. Whether you use W1239 or W1641 depends on the sliders and axle caps, not the hub/drum or brake.
Digressing slightly but to illustrate interchangeability:-
. early triples (built May, June, July 1968) have the notionally-'68 hub/drum and TLS brake plate between fork legs 6-3/4" apart, so on the notionally-'69 W2057 axle, brake plate engaging with the the notionally-'69 H2295 right-hand slider;
. '69 T100C's built well into 1969 still had notionally-pre-'69 7" hub/drum and SLS brake plate between fork legs 6-3/4" apart, so on the '69 W2057 axle, brake plate engaging with the the '69 H2295 right-hand slider.Hubs/drums and brake plates
The 'double flanged' (external 'flanges' for the spokes on both sides) hub/drum in "Hawaiian Tiger" Bill's picture was introduced in '68 with the '68-only
8" TLS brake plate (brake cable entry from the rear of the plate, "Irish Swede's loooong brake cable") and left-hand screw-attached hub/drum "Cover plate". Essentially the same hub/drum
, with the '69-on version of the TLS brake plate and clip-on "Cover plate", was used on the '69/'70 triples, 650's, T100R and T100T, '71-'74 T100R, '73 "BSA" T65 and some TR6P's supplied to Oz.
'66/'67 hub/drum has an external 'spokes flange' on the brake plate side only. This hub/drum was also used on early '68 T100R's (and T100T's?) that used up the remaining 8" SLS
Pre-'66 doesn't have any external 'spokes flanges'.
All the axles are interchangeable in all the hubs/drums and all the brake plates will fit over the axles, The only differences to watch out for are:-
. axles for 6-3/4" forks have a 20 tpi UNEF (Extra Fine) brake plate nut thread, axles for 6-1/2" forks have a 20 tpi Cycle thread, the nuts aren't interchangeable (I think
a UNEF nut might fit both but a Cycle nut doesn't fit a UNEF axle thread?);
. right-hand sliders for 6-3/4" and 6-1/2" forks, because of the width
of the brake anchor lug;
. 7" and 8" hubs/drums and brake plates;
. shoe width - later are wider because the spoke heads are in the external 'flanges', not inside the edges of the drum.
isn't the length of the brake plate anchor post of the timing side fork leg longer on the wider spaced forks?
Length (up and down the slider) is only relevant to 7"- or 8"-diameter brakes. The width
of the "brake plate anchor" on a '69-on slider
is greater because of the increased distance between fork legs, nothing to do with the actual brake plates.
This is further evidence that the forks are spaced wider apart.
I assumed "length" to be "up and down the slider" and "how far it sticks out from the slider" to be "width". The same sliders were used certainly on the C-range, some of which had 7"-dia. hubs/drums. Right-hand slider with a wider
brake anchor lug is used on '69-on 6-3/4" forks.
I have a 1969 TLS front brake on my 1967 T120R.
I did not use the later axle. I just swapped brake plates on the 1967 wheel.