Doug,
I have LDMCC machine register, which shows the G/box No (U145) for one machine only.  That code fits into 1936-37 motorcycles system. Did they change anything for the new lubricant?
Gerd

I wonder why they used 24tpi when 26 was so popular, didn't check the form though. 24tpi was popular with Triumph in the 20's

Kind regards Colin

Hi Steve,

The nuts on my Dragonfly were 5/8 x 24tpi, what thread form they were I don't know (whit or cycle)

Regards Colin

Hi Leon thanks have found him now will contact tonight

I have this printed www.barnstormers.co.nz/147/brown-barlow-carburettors-bb/

and this www.barnstormers.co.nz/barnstormers/wp-content/uploads/2009/10/Carburettors.pdf

found this www.vintage-motorcycle-spares.co.uk/brown-and-barlow-29-c.asp

would love to contact this guy www.flickr.com/photos/145850402@N06/25546706277/ but not sure how ?

Thanks Daren

Hi Daren,

Very difficult to answer your questions, because the 123-5 doesn't appear in the usual B&B literature, which would have us believe that the 123 carburettor wasn't fitted with a pilot jet, and yet the 123-5 clearly is. Perhaps it was made specially for Douglas?

Also 1928-1929 crosses the boundary between the old firms (AMAC,B&B, Binks) and the new (AMAL). Technically a B&B wasn't available in 1929, yet I bet they were supplied. Were some sold with AMAL float bowl lids? I don't know, but yours it the early AMAL type. I'd guess they had B&B lids originally, even if supplied in 1929.

Parts? I've suggested asking seller b561 on ebay before: he makes lovely parts and reconditions carbs, though more AMAC than B&B. Here's an example: https://www.ebay.co.uk/itm/143927411703

Here are the relevant parts lists, even though the 123-5 is not mentioned specifically.

Cheers

Leon