gt smiths

E

Evan

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Location
Texas
Are Smiths instruments the same on the Laverda Gts as on the Triumph sports cars of the same day? I could use one of those if I can't find anything...
 
This guy does them with Laverda logo on, think they bought up the Smiths factory.

http://vintagebritishcables.com/Smiths-Motorcycle-Speedo-Tach-Repair-Restore.php
 
Laverda used two different drive ratios in the front wheel for Smiths speedos and each matched a different speedo so you may want to check which you have first.
 
There were two different Smiths speedos with different maximum readings.
I don't think they are interchangeable with the instruments for British bikes but stand to be corrected.

Paul
 
and make sure the drive ring on the wheel matches the ratio of clock as there are two type , easily mixed up .
 
The 1.25-1 ratio may be the most common, it was used by early 70?s Brit bikes. Andy Wagners catalogue will tell you the 2 different front wheel speedo gear sets one of which is 15-12 to give the 1.25 to 1. The other I can?t remember without looking.
If you have the 1.25-1 set up and want a cheap fix I have found the copy Smiths speedos as sold for T120 etc to be good,( or I may just have been lucky.)
 
don't forget the 190KPH speedo Paul.

here are the two ratios

Smiths speedo with "/600" number in lower portion of dial, needs 12/15 (that's teeth on driving/driven element of the front wheel speedo gubbins)

Smiths speedo with "/1000" in the lower portion of the dial, needs 11/22 (as above)

twins fitted with ND instruments need 9/25 for both drum wheel type and disc type

Question, does anyone Know which motorcycle was fitted with a Grimeca front wheel/brake and had 9/25 speedo gear ratios, because all Laverda twins so fitted would have one or other of the two first mentioned ratios, and I know where there is such a wheel which wont work in a Laverda unless it get ND clocks. (not right for a 68 bike)
CLEM

 
you're welcome Shaun, please to be able to assist, must stop counting rivets and writing the results down.
CLEM
 
Interesting reply on a Facebook Smiths group but I"m no wiser to the problem,looks like wheel off to see what ring gear i have would be a good start.

"The 1000 refers to the turns the cable does in one mile (TPM) and the drive ratio should be 15/12 (1.25 : 1).
The 600 should be a KPH speedo and is 600 turns per kilometre (600TPK) and also uses the 15/12 ratio drive.
The 22/11 (2:1) drive is for 1600TPM speedos."
 
well interesting, they say 1000 with a 11/22 will read way too fast which it does.I ll see what I have and report back.!
 
Restored by Ashley Popple at Speedo repairs in Aldershot,,he has done all my clocks without issues,the needle goes of the scale after about 40mph, I"ll ring him as well as checking the drive gear.
 
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