B40 Valve clearances

[AdrianS]

A few people have said to me that my engine sounds like I have excess valve clearance. I appreciate it is a little noisy at the top end.
I find setting the valve clearances a bit hit and miss and a pain to do due to poor access but always set them as close to the wsm figures of 8 and 10 thou as possible.
I have heard that some set them a little tighter at 6 and 8 thou and also read that Rupert Ratio has a different way of setting them and as long as there is clearance when cold, all is ok as the clearance increases with engine temp.
I don't have Rupert Ratios book so not sure what he exactly says in it. Can someone enlighten me?
Interesting to hear what others do when it comes to valve clearances.

[JOHN KAY]

Hi Adrian  the book says he basically sets his clearances to virtually nil but does not accept responsibility for this < I guess it is up to the individual to try and see > I have just set mine to 2 thou each b25 starfire  after a recent rebuild and it is definitely quieter but I will check again later when engine is hot just to confirm just to be safe . the Rupert ratio  engine rebuild book is worth getting it is a goldmine of information on unit singles > I have all 4 reprints as well as the other 2 books for singles > hope this helps you regards johnboy .

[AdrianS]

Thanks John
That's what I assumed he said. I have set mine on the B40 to 6 and 8 thou and it is still noisy. It is a new rebuild with new valve guides and valves so after a few hundred miles they may well have settled in and the gaps may close a little. I have also found that the wsm for the B40 says that the valve clearances are to be checked in a different way to just setting the engine to tdc and checking the clearances.
I found it makes no difference to the clearances which ever way they are set! I have also checked several times to be sure.

[JulianS]

I suggest set valve clearances as per BSA advice - doing it that way the cam of the valve being check is on its base circle. Checked at TDC the cams will be on the quietening ramp part of cam - the clearance is already being taken up for the valve being opened.