No, the springs are not the problem, it bounces up quick enough, actually to quick. I have used fork oil SAE 10, the highest SAE fork oil the shop had, but from what I can find in manuals, it should be SAE 20.
I have now put mineral SAE 30 oil in the forks, and 200 ml, not 140 as the manual says, and it is better, but still the girder fork on my Ariel feels better.
I will leave it by now, and try it on the road, as soon as I have rebuildt the engine and gearbox ;-)
Oyvind
From what I have been told, the bike was used by the norwegian airforce. I have no records to prove it, but I keep looking