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My name is John and I manage East Atlanta Village Hardware. We are an Ace store but we cater to a very eclectic urban crowd that includes quite a few vintage riders. We even have a spectacular vintage British repair shop around the corner called British in the City. I spoke with Eric there and he informed me that vintage hardware is not metric but British Standard. I did a little research and learned that British Standard Whitworth is a group of hardware that includes several thread patterns. Does anyone here know which of the thread patterns are used on the classics. This is something that we have an interest in possibly bringing in and stocking. We may even pursue some internet sales as we develop our business.
I am a Thunderbird Sport rider but I hope to learn more about vintage and possibly take the plunge in the near future.
Thanks,
John
 

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john
welcome to our august group of ruffians, derelicts, winos, and general roudys known as the vintage forum. :yayyy:

Depending on the vintage of your vintage bike (which I assume will be a Triumph) the fasteners used will vary.
Vintage bikes used BA, BSF,BSW,CEI, UNF(same as US FINE), UNC(same as US COARSE), and in later years Metric.
:knkknk:

I applaud :clap: the nobility of your intentions but I fear you will reap financial disaster. This is one time where ACE ain't da place :wow:
 

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Hi John-

The older Triumphs used CEI (Cycle Engineers Institute)/BSC (British Standard Cycle) threads. BSC superceded CEI, but only by dropping standards for some little used threads. If I recall from the comments of more knowledgable members, in 1969 Triumph engine threads were changed to UNF; thereafter the bikes had a combination of CEI/BSC, UNF, and later even some metric.

BSW(British Standard Whitworth) is an English coarse thread standard; BSF (British Standard Fine) are actually different and I'm not sure they were used on Triumphs at all.

I believe the CEI/BSC and BSW/BSF used the same wrenches; same measurements across the flats, but used different measurements to describe the size of the wrench, leading to even more confusion.


Good info at this site: http://www.britishfasteners.com/Merchant2/merchant.mvc

Look down the column of links on the left side of the page and click on "Learn About British Threads".
 

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The bad thing is that you can find similar threads in TPI (threads per inch), with the same diameter fastener, leading you to think you can use the replacement fastener. You start to fit it up and it's tight, so you go ahead and "force" it (admit it, who hasn't done this?)

You end up with mangled fasteners and damaged internal threads because the pitch/angle of the threads is different!

Imagine steeper "peaks" and "valleys", with the same number of threads per inch...
 

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British generally use 55 degree form and US 60 degrees. CEI and BA have rounded thread roots.
 
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