I think it’s very important to keep any motorcycle fit for purpose. I owned a lovely BSA A7SS in my youth (mid 1970s). It went well and handled very well, but its weak point was the SLS front brake. To get any worthwhile retardation one needed to pull the lever so hard it felt like the nipple might pull off the cable. I wouldn’t want to have to rely on it in modern traffic conditions, which in U.K. has become exponentially busier and faster.
I was in the RAF in North Yorkshire and a pal, who hadn’t long passed his test, bought a Yamaha 200 twin, fitted with a single disc front brake. One evening we went out for a ride around the county and my pal asked if we could swap bikes on the way home and I agreed. I was surprised by how light his bike was. As it was getting dark, we were batting on a bit with me leading and came to a T junction leading to a main road, where we had to stop. Not being familiar with disc brakes, I used my usual vice like grip on the little Yammie’s brake lever, which instantly locked the front wheel. I nearly went over the handlebars and stopped twenty yards short of the junction. Seconds later, my pal flew past me on my Beesa, went straight across the junction, over the main road onto the opposite grass verge and almost into the hedge.
There were a few expletives uttered but his involved my brakes not working. They did, but not if you only used a couple of fingers to pull the lever!
Anyhow, if I had the A7SS today the first thing I’d fit would be a 1969/70 BSA/Triumph TLS with some decent shoe linings. I fitted Villiers Services shoes to my 350 Bullet and it will now lock the wheels.