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Hercules Front axle size

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Eatontkd

Finally riding a big boys bike
I'd like to install wingnuts on my Royal Prince. I know they're 8mm but the pitch is nothing I can match. What am I missing?
 
8mm?
Pretty sure they're standard English thread.
Hercs are pre metric in England. I think i read right here that metric measure showed up in the 70s there.
My 62' Herc has 5/16
A set of Gripfast off ebay would be the originals. I bought a new set a few months back.
 
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The older English machines are pre-metric, but they're not SAE either. The industrial revolution started in England and they developed some early standards that were never adopted by anyone else. American threads are often the same diameter but the pitches are usually different. You probably want Whitworth or CEI threads.
 
Except they are the same EXACT threads that are on my 62' and not special at all. The Gripfast that fit my 38' Armstrong fit my 62 Hercules which fit all my Schwinns.
No need for speculation or further confusion.
.... Or (at least in my posts) spelling and grammar corrections when it's obvious what's being talked about
 
8 mm converts to 0.315 inches, while 5/16 is 0.3125, so you probably want 5/16 threads of some pitch. If you have a ruler, see if you can count or estimate how many threads there are in an inch, English and SAE pitches are always given as threads per inch.
 
You'll want to look for a Whitworth/BA thread chart - most old British threads are obsolete, and have odd thread pitches.
I work on antique fishing reels, and found a tap for BA7 thread (small stuff) in Canada.

I think @Schwinny has you covered on the OS Gripfast wing nuts.
 
Have to correct myself.
The whole of this thread is correct. The op can get a set of Gripfast wing nuts and that'll do.
But I am changing the hub on my old Schwinn today that has a set on it and it isn't a Schwinn hub. I assumed it was, being tied to an old s6 but it is an english hub. So it's 5/16 26tpi same as all the old english bikes. I said the gripfast fit it and made it sound as of it was normal.
Not so. schwinn's axles are 24tpi 5/16
 
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