Featherbed Swingarm Spindle Threads?

[johnod]

Anyone happen to know what thread the stock slimline spindle is?

Thanks

 

[bad_friday]

Have a look here: https://andover-norton.co.uk/en/shop-de ... -x-20-whit

Fritz

 

[johnod]

Perfect, thanks very much.

 

[Rohan]

While that gives a good source to obtain those nuts,
folks should be aware that that description is seriously in error !

20 tpi in a 1/2 nut is NOT Whitworth, its a coarse Cycle Thread (also called CEI) special....

Whereas a true whitworth 1/2" nut would be 12 threads per inch.
And a UNC 1/2" nut would be 13 tpi.
That variation the cause of much damage in the mechanical world...

 

[Mark Savage]

Is there a difference between 1/2 inch Course Cycle thread and 1/2 inch UNF. They both have 20 TPI and a thread angle of 60 degrees?

 

[Rohan]

One has rounded peaks and troughs, and t'other (UNF) has flattened peaks and troughs...

I just screwed a 1/2" UNF nut onto a wideline swingarm, and it went quite easily.
Very easily - quite a loose fit, it should be noted.
The original British nut is quite a deal larger than the UNF one too.

Now you have let the cat out of the bag, so to speak. !
Probably do in a pinch, but I wouldn't like to have to rely on it...

 

[grandpaul]

"For What It's Worth"

I offer an upgrade kit that fits all featherbeds and takes less than an hour to install (NOT including however long it happens to take you to remove YOUR old metalastic bushes!)

$150 + postage (about $12 in the U.S.)

Similar to what the racing crowd used on Manx's.

 

[Rohan]

Looks neat.

What pivots on what, and how is it lubricated ?
Do you need to drill holes in something ?

 

[grandpaul]

140W, just like a Commando. o-rings keep it where it's supposed to be.