whitworth tools
- Thread starter MikeM
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ashman
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Its one of the first things you should have brought when you take ownership of a Norton, congrats anyway, now you are a true beleiver and it will make life much easier for you, I have a full set of WW open enders, open and ring combind and full set of sockets, I went years without WW tools not knowing about them at first but now have used mine on a few mates Nortons over the years, but some of the Nortons I have worked on had nuts and bolt heads damaged because they didn't have the right tools.
Ashley
Ashley
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My whitworth wrenches are marked such as 1/4W etc. Gets confusing with the different British fastener standards as per Wikipedia. SAE wrench sizes are the distance across the bolt or nut hex flats.
(To simplify matters the term hexagon will be used in this paragraph to denote either bolt head or nut.) Whitworth (spanner) markings refer to the bolt diameter rather than the distance across the flats of the hexagon (A/F) as in other standards. Confusion also arises because BSF hexagon sizes can be one size smaller than the corresponding Whitworth hexagon. This leads to instances where a spanner (wrench) marked 7/16BSF is the same size as one marked 3/8W. In both cases the spanner jaw width of 0.710 in, the width across the hexagon flat, is the same. However, in World War II the size of the Whitworth hexagon was reduced to the same size as the equivalent BSF hexagon purely to save metal during the war, and they never went back to the old sizes afterwards. Thus it is today uncommon to encounter a Whitworth hexagon which takes the nominally correct spanner. Spanners in this case may be marked 7/16BS to indicate that they have a jaw size of 0.710 in and are designed to take either the (later) 7/16 BSW or 7/16 BSF hexagon.[3]
(To simplify matters the term hexagon will be used in this paragraph to denote either bolt head or nut.) Whitworth (spanner) markings refer to the bolt diameter rather than the distance across the flats of the hexagon (A/F) as in other standards. Confusion also arises because BSF hexagon sizes can be one size smaller than the corresponding Whitworth hexagon. This leads to instances where a spanner (wrench) marked 7/16BSF is the same size as one marked 3/8W. In both cases the spanner jaw width of 0.710 in, the width across the hexagon flat, is the same. However, in World War II the size of the Whitworth hexagon was reduced to the same size as the equivalent BSF hexagon purely to save metal during the war, and they never went back to the old sizes afterwards. Thus it is today uncommon to encounter a Whitworth hexagon which takes the nominally correct spanner. Spanners in this case may be marked 7/16BS to indicate that they have a jaw size of 0.710 in and are designed to take either the (later) 7/16 BSW or 7/16 BSF hexagon.[3]
The size marks on Whitworth wrenches refer to bolt diameter, not the across flats size, like SAE wrenches do. I'm going from memory here and it's a long time since I was a drafter.
I think the equation was originally that the a/f dimension was 1.5x the bolt diameter +1/8". It was later changed (sometime during WW2, I think) to 1.25x bolt diam +1/4".
I think the equation was originally that the a/f dimension was 1.5x the bolt diameter +1/8". It was later changed (sometime during WW2, I think) to 1.25x bolt diam +1/4".
freefly103
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When you grind down one of your shiny new wrenches to fit between the cylinder head fins, that's when you're addicted, or at least, that's when I knew I was. Welcome to the madness.
You must have a complete set of all three to do proper work on these bikes. During the 70's there was a transition to a single unified nut and bolt situation but many older assemblies like barrel nuts and head bolts still need WW wrenches and sockets. Just part of the charm of owning and working on one of these exclusive gems of motorcycle history.
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