From StainlessSteelFasteners.com website

As you have probably discovered, your vintage parts catalogue doesn't list specific sizes for nuts, bolts, washer, spacers, studs and clamps. You get a picture of the part and a part number, but no clue as to diameter, length, thread pattern or any other vital data.

The list below is intended to help you determine exactly what to look for when working on your bike. Just hit the Ctrl-F keys on your keyboard. A search box will pop up. Put in some or all of the part number you are looking for and hit the "Find" or "Find Next" icon with your mouse.

The list has been compiled from several sources. As you will see, it is not complete. Quite a few items show only a part number and the type of fastener with no dimensional data. I will try to fill in these gaps as I get more information. Items with "???" inserted are missing obvious data.

While the vast majority of the data is correct, there may be flaws in some items. Please note that several items have long strings of question marks. These items have data in them that seems to be contrary to the general rules Triumph and BSA used in their numbering system. In one example, all data sources indicate that a bolt has a CEI thread pattern, yet the numbering rules clearly place that bolt in the UNF pattern sequence.

Also note that British bikes have some unique fasteners manufactured for specific applications. Common examples are the bolts used to secure side stands and center stands. These usually have a stepped shoulder. The part list usually has a note, but might not indicate a specialty item.

Fasteners for some applications require hardened steel. Care should be exercised when replacing critical stress items, like head bolts, wheel bolts, suspension bolts, and similar applications. Stainless Bits carries a full line of Aerospace spec hardened stainless bolts in hundreds of sizes.

If you decide you want to replace your fasteners with stainless, I hope you will do a little price checking here at the Stainless Bits site. Just click on the "SHOPPING" button at the top of this page. At this time, Stainless Bits offers UNC, UNF, and a few BA pattern fasteners. I have yet to find a reliable, cost effective source for most of the British standard threads in stainless.

If an item is not listed in the database, please ask about it. The "Stud" section is not active yet, but I stock, can get, or will manufacture most of the UNC and UNF studs in stainless. The same is true for the "Metric" section.

And, last but not least, be sure you always use a thread compound with stainless fasteners. Thread locker or anti-seize, whatever the particular application calls for.