Filling forks with oil
Back in the day, bikes like the AS1 were often said to be ‘over-sprung and under-damped’ – which was, and remains, a fair criticism. The fork’s damping varied from primitive to non-existent due to a very basic internal design and the Japanese often using very thin oil, which only exacerbated the problems. Some of the underdamping can be addressed by using thicker oils, and those that know reckon you could do far, far worse using a straight SAE30, which is what I’ve used in the restoration. Pouring thick oil into 10mm holes is never easy at the best of times but there are ways to make this a quicker, cleaner and stress-free job. Heating the requisite quantity up reduces viscosity and cutting the end of a plastic funnel to the widest possible diameter to fit in the fork top gets the oil flowing faster. There’s always air locks which pretty much stop the oil from draining down where it’s needed, but there are a couple of solutions. If there’s sufficient space, a drinking straw provides an escape path for the trapped air. Alternatively, regular dipping down into the funnel with a long, thin screwdriver will allow the air to pass through the oil above it. Don’t work harder, work smarter – as they say.