struggling with the button layout of the Lucas switchgear on my bike.
can’t reach the RH buttons with my thumb without loosening my grip on the throttle, the cable twist mechanism gets in the way.
Something not solved 'til the black switch clusters (first fitted to the '75 electric-start Commando but not fitted to Triumph twins 'til '79
RH functions are top/hooter and bottom/main beam flasher both of which I’m more likely to need whilst riding. The LH functions are top/engine kill and bottom/redundant, my thumb reaches them easily on the move but I never need to use them.
Ironically the functions you want were how the switches were originally fitted in '71 - except the stupid up-down indicators switch was then by the twistgrip ...
The one you can't change (easily) is engine kill - it's a push-to-break button while the other three are push-to-make. If you really want to change this, you need two relays (the relays could be fitted inside the headlamp shell depending if the standard wiring in there needs tidying and you're prepared to do it); I can go into the relay requirement in more detail if you wish?
If you didn't want to get into relays, you could still swap one of hooter/main beam flasher to LH "bottom/redundant":-
. LH "bottom/redundant" is the White/Red wire, supplied by a White wire;
. hooter is the Purple/Black wire, main beam flasher is the Blue/White wire (not confused with dipswitch Blue/White), both supplied by White wires;
. simply disconnecting and insulating the desired function's button wire/terminal from the main harness and connecting the White/Red to the main harness in its place will transfer the function to the LH "bottom/redundant" button.
. On my T100, I fitted the T160/'76-78 twin LH switch cluster (dipswitch, left-to-right indicators switch, horn and headlamp flash) and, when I get around to it, a Hinckley kill switch on the RH; on your bike, you'd also need to swap to the pre-'71 chromed steel clutch and front brake levers that clamp on the 'bars.
. With the chromed steel levers, another potential alternative is a Hinckley LH switch cluster, it has the same functions as the T160/'76-78 twin switch cluster, is mainly black but has a couple of red bits.
. Or, keeping the existing levers, yet another potential alternative - if you could live with RH indicators switch and LH dipswitch - is to swap the clusters side-for-side, fitting at least the indicators switch with a later longer black lever that's reachable from the twistgrip with the standard human thumb. You'd have to put up with the dipswitch working the 'wrong' way (up-for-dip) unless you could source the earlier '71-to-mid-'72 cluster (the one not patterned by Sparx ...).