Speedo drive ratio and sprocket

pierodn · Sep 18, 2016

Hi.
Please, what is the speedo drive ratio?
Howh many theet has the gearbox sprocket?
Thank you.
Piero

Mike B · Sep 21, 2016

The original size sprocket is 19 teeth. The speedo drive ratio is the same as Atlas, but the drive itself is different.

Mike B.

L.A.B. · Sep 22, 2016

pierodn said:
Please, what is the speedo drive ratio?

2:1 according to my Smiths list. The P11 drive gearbox was BG 5330/257 and the speedo was SSM 3001/00.

pierodn · Sep 22, 2016

Hi Les,
Thank you.
Ciao
Piero

Sloppy Link · Mar 22, 2019

Anyone have a source for the speedo drive? Mine is shot, the replacement from Andover Norton cannot accept the spacer as the centre hole is too small.

Ron L · Mar 22, 2019

It should take a BG5330-257 2:1 drive with a 3/4" center opening. Baxter cycle has some NOS Smiths for a lot of money, a Taiwan replica for a lot less, and an Indian replica for a little. My guess here is you get what you pay for. I'll only use Smiths on mine. https://www.baxtercycle.com/product-category/cables/speedo-drive-gearbox/page/2/

texasSlick · Mar 22, 2019

If you can get a NOS Smith's drive, spend the money. The knockoffs are junk.

Slick

CanukNortonNut · Mar 22, 2019

L.A.B. said:
2:1 according to my Smiths list. The P11 drive gearbox was BG 5330/257 and the speedo was SSM 3001/00.

Les, I have a BG5330/267 would that work?
Cheers,
Thomas

Ron L · Mar 23, 2019

BG5330-267 has a 7/8" bore and 2:1 ratio while the 257 has a 3/4" bore. You may need to make a special bushing to centralize the gearbox on the spacer/bushing setup (P/N 28070 and 28073).

CanukNortonNut · Mar 23, 2019

Thanks Ron,
Cheers,
Tom

Speedo drive ratio and sprocket

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