I dunno. I'm old fashioned perhaps. There are people calling me by my name, which is fine, but I've no idea who I'm talking to. Feels weird. Never mind. Can I call you John?
You are arguing against yourself slightly. As a scientist I totally agree with the need to measure, remeasure, modify, test etc. Objective data points rule. But you make a subjective value judgement about the compression damping not being adequate. Inadequate for what? Judged by whom? Under what conditions and for what purpose? Without those basic qualifiers you can't sustain your view as being superior to anyone elses, which is fine if we're just joshing but not if we're claiming technical precision.
I can pretty much guarantee that Mick Grant or Peter Williams on an old heap with no fork oil and worn isolastics could blow us off on race-fettled machinery, so in what sense were those old nails inadequate? I never really had a compresssion problem, but then as you can see from the bike photos I also made linked air assistance and variable damping for my Roadholders too, plus somewhat of a fork brace. Not too shabby for a total autodidact who didn't even do woodwork, let alone metalwork at school. Frankly, it would take me some time to get back to the screw cutting etc I did back then.
I even took my home made belt drive to Mick Hemmings to ask about tooth cutting for the then-new HTD belts - the only UK location with a licened tooth cutter was in Scotland IIRC. A few months later, guess what, Mick starts selling belt drives just the same as the one I showed him and then everyone was doing it
A few years later I beat him in the MCC high speed trials at Silverstone in the pissing rain and was first British bike home, but honestly there weren't many entered and Mick would have beaten me if his crank cases hadn't been inadequate. That's NOT a value judgement, because there was about half an inch of fresh air where the barrel should have been (all subject to dodgy memory).
Same with your statement about the thin ring of oil being inadequate to prevent topping out. It did on mine and did on a Le Mans car racing friend's Commando that I rebuilt for him. 2 out of two that I did, but still only a small sample of course.You and I would have fun in a workshop. We would need to find where was it topping out - the damper valve as original, or some mismatch in parts dimensions somewhere. Did you read the article where it says how I discovered this, by wheeling my engineless (therefore massively over-sprung) alloy chassis around and noticing the clanking? I did the work, measured everything and got the ring of oil working and no metal clank. QED. I dry assembled fork legs, wet assembled them, with/without springs. Norton, matchless and Triumph. There. Was. No. Clanking on short Roadholders with the small hole left open, as long as there is oil and the sleeve/bush overlaps the holes on full extension. I think your split sleeve idea is neat if installed right, but one finger dab of silicone or drop of blue non-hardening Loctite is not exactly hard to reverse for dismantling. YMMV etc.
Remember that I was a 33 year-old medical information specialist and total amateur engineer. Can you imaging how vulnerable I felt publishing a paper critical of a design that in those days was regarded as the finest Brit fork, sought-after and boasted of by owners in the small ads. Who the heck was I to take them down? Nowadays everyon can say they are flawed and nobody bats an eyelid.
