Gold Star valve clearances
I’m used to setting valve clearances precisely with feeler gauge strips. I believe this vital for best performance.
Working on a customer’s BSA Gold Star, I find I can’t use feeler gauge strips due to design. The BSA workshop manual states adjust clearance until ‘…there is no up/down play for the pushrod but it still freely rotates when spun by fingers.’
All seems a bit haphazard to me – is there a better and more accurate way, and, if so, what are the clearances and how can I measure them?
The method you’ve found is exactly the way to adjust valve clearances for BSA Gold Stars like the one you are working on, and it’s not uncommon for single cylinder machines from pre Second World War days onwards. We do exactly as per BSA manual for my son’s 1959 DBD 34 Clubman’s and my ex-proddie racer built in the 1960s/70s from a 1955 DB34. Both perform well and as expected with regard to their differing states of tune and we’ve never had problems with regard to valves failing to shut efficiently, which you allude to and think will happen with seemingly tiny clearances. Conversely, there is no valve clatter as one hears on some other machines either.