Gear change selector question

[Lynn Eades]

Alex, I was trying to make it easy for Stephen, who, being from the U.S.of A.,is probably not very familiar with British thread forms.
While you are being so precise, it would be more accurate to say that BSC threads were used in some old leaky motorcycles.
How is that carrier coming together?

Stephen, as has been pointed out, It is referred to as Whitworth, or British Standard Whitworth.
1/2" is the problem size as it is 12 TPI where as 1/2" UNC has 13 TPI.
The other common sizes 1/4", 5/16", 3/8", and 7/16" are the same TPI as their counterparts (BSW and UNC)
This is not the case with the fine threads (BSF and UNF)

[SDeMocko]

Lynn,
I have one of the newer Triumph Bonnevilles. No Whitworth threads but it does leak. Does that count? Thank you all for the info. I am not sure where I would be without all of you. Lynn, thank you for asking about my progress. I did have an exciting weekend just past as I put the track back on after about a 1-1/2. I just need to get the engine running right. Some seats and armor might be a good Idea too.
Stephen DeMocko
’44 MKII
So Cal, USA

[SDeMocko]

I dont know guys, 4-1/2 threads over 1/4" sure looks like 18 pitch to me. A forum friend (Thanks Mike) says the nut from the bottom of the steering column goes on ok. I have one coming from Brian A. (thanks Brian). Maybe its 20 but it seems less as it was a bit hard to get my calipers in there especally as i use them as scribs sometimes. Ends are warn a bit.

Stephen DeMocko
'44 MKII
So Cal, USA

[Lynn Eades]

Your last post caused me to look at another column that I have, and that one is 3/4" dia. x 16 tpi, which is UNF thread.

If you are buying a bearing for here be careful with the size.
The ring on the floor and the inner diameter can be different sizes.
The imperial self alingning bearing is difficult to find and can be expensive.
I have one that so far, I have been un able to remove from the column.

The Australian carriers used metric sizing and use a cheap and easy to get 6304? (check) bearing.

This leads me to mention that I have found on Canadian carriers, that there are bolts which are hybrids (I am talking original bolts)
Some are UNF threads, that fit the British spanners, and some are BSF that fit American sized spanners. I'd be interested to hear comments from others on this.

[Michael R.]

The nut that fits on the top of the transmission shift lever should be a 1/2 B.S.F. hex., (slotted). The part number is CO1UC 103010. It is also known as U.K. No. MT5-9936. Reference FUC-03. Looking at Chilwell, the LV6 MT5 P/N 9936, Nut-Slotted 1/2" appears. That 1/2 B.S.F. nut can be found on Carriers in the No.1, 2, 2A and 3 series, with Mk.'s I, II and III.


Should a 1/2" B.S.F. nut fit a thread count of 16 TPI ?



I previously mis-identified TL2868, Nut, slotted that fits on the bottom of the steering column when describing one of the three locations where the 1/2" B.S.F. nut, part number CO1UC 103010 appears.

[Lynn Eades]

Yes. 1/2" BSF is 16 tpi

[SDeMocko]

Guys,
I know it says in the manual that the nut that goes on the gear selector shaft is ½” BSF, but at least for the shaft in my hand it is not 16 pitch. The nut I made using the ½” BSF 16 pitch tap in the pic will not fit on the shaft. The second picture also shows a thread file with the 16 pitch rotated in contact with the shaft threads and you can see that they do not match.
Stephen