English French German Italian Spanish

Speedo for 1961 ES2

Submitted by richard_salt on Fri, 17/05/2019
Forums
Nortons - General

I am rebuilding a 1961 ES2 and the two speedos which came with the parcel of parts are:

1. Smiths Green Circle 150 mph(!) SSM 3001/02 1000

2. Smiths Grey Circular center 150 mph(!) SSM (5001/06 1000)?

See photo

The numbers on 2. are indistinct, maybe wrong.

I think that neither are correct for the bike.

I assume the speedo drive is 2/1 but haven't checked it yet.

Can anyone tell me what I should have, and how far out these will be.

Thank you.

 

Attachments
Speedos.jpg

Submitted by philip_chester on Fri, 17/05/2019

Permalink

Hello, The Smiths motor cycle equipment info for 1961 I have gives the speedo number as 

SC.3303/17.  The same speedo was also fitted to the model 50,  88 and 99  for this year. The gearbox number is BG.5330/257 again applicable to all models as was the length of the speedo cable at 5ft 7 1/2 inches. Hope this helps, Phil

Thank you for this Philip, so the two I have are not correct for the bike, as I thought.

Does your catalog give any information on the ratio of the speedos, i.e. number of cable turns per 0.1 of a mile?

If so, are either of my two also given? In other words, can one of the two I have be used with reasonable accuracy?

Thanks again for your help.

Richard

Submitted by michael_sullivan on Fri, 17/05/2019

Permalink

My parts list shows that the speedo for all models in '61 except for 650 models should be:

   p/n 19364 and it is shown to be for 120 mph 

On my '61 Model 50 the speedo shows as SC3303/17  and 1548

I believe that the 1548 refers to the turns per mile.

Mike

 

Thank you for this Mike,

It looks like I am going to have to investigate further.

Diameter of rear wheel, number of turns of wheel for 1 mile, gearbox ratio (2/1), number of turns of the cable for 1 mile.

This will tell me how far out they are, if they can be used.

 

Submitted by alan_sessions on Sun, 19/05/2019

Permalink

The green blob speedo is from an early Commando  and the other looks like those fitted to Triumphs T120/T150 from the mid 60s - both magnetic and use 15/12 speedo boxes - if the Smiths speedo part number has 1000, it uses 15/12 - if the number is 1600 it uses a 2/1 box

Submitted by ian_richtsteig on Sun, 19/05/2019

Permalink

My Smith's catalogues from 1960-1963 list the speedo for all models except Jubilee, Manx and Nomad models as SC.3303/17 (in mph) with complete flexible drive DG. 1110/22 of length 5ft 7 1/2 inches.  Drive gearbox  part no.  BG. 5330/257

In 1959 the speedo fitted was S.467/203/N

Hope this helps 

Submitted by richard_salt on Tue, 21/05/2019

Permalink

Thank you all for the valuable - but disappointing - information.

Both the instruments I have then require a 15/12 gearbox, but the bike has a 2/1 box.

So they will be seriously overeading.

As the bike is not been prepared for strict originality, I was hoping I could use one or the other of them.

I need to search further but not much chance of finding the correct instrument here in South Africa.

Thanks again.

Submitted by alan_osborn on Mon, 27/05/2019

Permalink

Fine that you might like to use either speedo if possible, but of course if you can't get the right one, then changing the speedo box might be a cheaper option. The 15/12 being the commando box and relatively easy to find.

 

 



© 2024 Norton Owners Club Website by 2Toucans