My BSA

[RidgeWalker]

I recently completed the rebuild on my 1950-1956 BSA, Birmingham Small Arms, StreamLight. I've been commuting to work on it for the past couple weeks. The bike is pretty original though I have replaced the seatpost, saddle, tires, pump, grips, and shifter. The shifter is a BSA "Snap" and is not correct for the bike as the bike originally had the optional twist grip. I added the Lucas "King of the Road" bell, off my '47 Raleigh, to the BSA.
In March I plan to take the bike to my machinist brother-in-law to see if he can make the threaded pin I need to make the twist grip work. There will be some additional tweaking, like gearing it down from 18 to 22t rear cog, but I plan to keep it as original as possible while making it 100% rideable as my daily commuter.

 

[Oilit]

Was this built by the motorcycle company, or had they sold off this part of the business?

 

[bulldog1935]

Raleigh (TI) acquired BSA in 1957

in case you've never used it, Sheldon has a really good gear calculator that incorporates IG hubs.
http://sheldonbrown.com/gears/
just plug in tooth counts for your chainring and choice of rear cog, pick the correct IGH, and can get the answers in any format you choose.
Most IGH guys prefer gain ratios, but being conversant in gear-inches is usually most helpful.
(gear inches is the equivalent wheel diameter if it was direct-drive, or better, the size wheel it would be on a penny-farthing)
You typically want your high gear around 75-80 inches. Good climbing gears are below 45 inches.
I plugged in a 1902 SA 3sp with 46T/22t, and got 45", 57" and 71" - not bad at all, and versatile for 3 gears.

 

[RidgeWalker]

https://en.wikipedia.org/wiki/Birmingham_Small_Arms_Company
Wikipedia is a good source for company history, BSA dabbled in a lot of different businesses.
Their first bicycle appears to have been made in 1869. Their first motorcycle was apparently introduced about 1910.
From the wikipedia source: "BSA Cycles Ltd was set up in 1919 for the manufacture of both bicycles and motorcycles. BSA sold the bicycle business to Raleigh in 1957 after separating the bicycle and motorcycle business in 1953."

 

[bulldog1935]

Then there's the BSA Bicycle Museum - https://bsamuseum.wordpress.com/
Largely aimed at military bikes, it's a wonderful resource for information, photos and paper from the first century on pedals.
It's actually how I found this forum - it links to the military bikes page on The CABE.

I always wanted a BSA Martini target rifle, but never got around to it - instead, bought a Uberti replica 1885 falling block.

 

[RidgeWalker]

I've seen Sheldon's gear calculator and it is quite useful. I'm not sure if the BSA hub has the same 25% reduction and 33% increase from direct drive though I would guess it does.
The BSA hub is quite different from the Sturmey Archer hubs I'm familiar with, though I don't have experience with the earliest models.
For example, the BSA hub is in high gear when cable tension is at its tightest. This is reverse of the Sturmey hubs.

 

[SirMike1983]

Sounds like you have the BSA hub model heavily based on the Sturmey Model X of 1905. The Model X design was re-purposed by BSA at a later date.

http://www.sheldonbrown.com/sturmey-archer/bsahub.html

 

[bulldog1935]

Sounds like you have the BSA hub model heavily based on the Sturmey Model X of 1905. The Model X design was re-purposed by BSA at a later date.

http://www.sheldonbrown.com/sturmey-archer/bsahub.html

from Sheldon, you get even a better/wider range with the SA-X, and 46T/22t
43" 57" 74"

 

[fat tire trader]

Here's mine

 

[RidgeWalker]

It's hard to tell from that picture, but yours is a bit different from mine. Is it a Sturmey Archer rear hub, or BSA? If it is Sturmey then yours must be '57 or later, assuming the equipment wasn't changed from new. Curious bike. I'd be interested in more pictures if you have them.