That's assuming, Paul; that both sides haven't been leaking badly - or have been overfilled. So yes check the air gap.
OK no problem. But I will point out my forks are always cleaned right out and dried before any reassembly, so apart from a minor wipe of oil around sliding parts, I refill with the specified and exact amount in each leg. However when re-valving to improve performance, it can get more complicated like drilling out little spot welds to remove the compression stack, and sometimes re-drilling bleed holes (and sometimes reducing the length of the damper tube).
On my old blackbird forks when upgraded springs or just fresh oil was needed, it was recommended oil level/input as the start point but the air gap as the definitive.
Okay guys. Red faced time Completely stripped the job down again and built the fork back together. No idea what I possibly could have done wrong before, but both forks are now working as expected!! Thanks for your insight, I’ve learnt a lot. This forum is fab and I’m glad to be a part of it. ...I’m also ready for the abuse for being an absolute tool Plenty more fettling to be done before it’s ready for the TT next year. Including an oil leak in the horizontal cylinder. Right at the base of the barrel - I’m in surgery next Saturday, so it’ll be a couple of weeks before I tackle that one. I’ll start a new thread for any tips before I start this time. (I’ll also only start one thread, now I’ve got the hang of it) Cheers
Truly, this forum has been really helpful. I’m subscribing this month. The guides and past posts are invaluable. Plus, if you put a post up, people actually respond and try their best to help. Deffo worth subscription.
