Sturmey Archer LS250 pinion

[FPButer]

Hello,

I am piecing back together a Sturmey Archer LS250A gearbox that belongs to my 1929 model B.
Previous owner took everything apart back in the days, so it has became a puzzle.
Most parts are there but I am missing the smallest of the six pinions.
I believe it is part number LS138, but I am not sure.

Two questions:

- How many teeth would that pinion have?
- Is there someone in the community who is familiar with these gearboxes

Thanks in advance, regards, Rik

[john.whiting]

You may be able to simply add the tooth numbers in each gear pair.........in an ideal situation,these will be equal.....but bike boxes often "faked " the pitch circle of gears to achieve desired ratios.....You appear to me missing the small first gear pinion....the one that meshes with the large kickstart /first layshaft gear.

[FPButer]

Thank you John.
Second and third gear both have 42 teeth total.
First gear single pinion has 28 teeth, so the other pinion should have 14 teeth.
So I need LS138 14-teeth pinion.

I believe it is the same smallest pinion in this picture I found on the internet, although it is a LW or 2-stud gearbox.

[Bob.Murphy]

I needed a gearbox pinion for the LS240 box from my 1931 Panther. I managed to get one from Mark Upham at 'British Only Austria'. If you're stuck give them a call.

But be sitting down when they tell you the price .

Bob.

[john.whiting]

The other thing I will mention is that the Sturmey 3 sp gears bear a resemblance to their descendant,the 4 sp Norton box 1934 -1956.......First I would see if a Norton Ist gear will fit .......they are certainly 14t/10DP...and six spline shaft.....Sturmey stuff is hard to find because there are so many tossers making fake Brough s and Zeniths........Which is where all my Sturmey stuff went.

[nevhunter]

At one time there were heaps of 4 speed WD Norton Gearboxes from India. I bought a couple of them brand new at the time. They fit Broughs 32 on . I've worked on quite a few Broughs but never owned one for obvious reasons. Set up properly the OHV models are a good goer (for the time) and the Bentley & Draper rear works ok too. Close to being the most collectable brand out there. A Coventry Eagle of the same period is as good a bike and better for sidecar work (stronger frame).
I get just as much out of riding a good Ariel or HD sportster depending on the situation. Having the bike set up and running well makes it enjoyable. If it's running off song it's not much fun. Nev.

[FPButer]

I've asked "British Only", awaiting reply.
I'll make sure I'll be leaning back in the recliner

Is this what you mean:

https://www.britbikes.co.uk/norton-comm ... 4793-p.asp

Or this:

https://www.ebay.ie/itm/NORTON-COMMANDO ... Sw0Pxa2LC6

You believe the spline is the same?
Maybe have to shave the width down?