will triple tree and fork crown from a 66 fit a 69?
are fork sliders interchangeable?
Depends on the bike.
As Jon posted, 500's and 650's are basically the same but there are some gotchas:-
. as "kommando" posted, pre-'69 yokes ("triple tree and fork crown") place the fork legs 6-1/2" apart, '69-on (to '74 on the T100) are 6-3/4" apart;
. pre-'69 brake anchor lug (timing-side slider) is narrower than '69-on lug.
So, while the '66 yokes'll fit a '69 frame, they must be fitted with a pre-'69 t-s slider and front wheel axle. Pre-'69 Fasteners
are Cycle thread, '69 are mostly