Need a 3.64 ratio Speedo Gear & Trip Mechanism For a '75

[Captain Manly]

A bit of a refresher but I am in need of guidance.

 

I have a 140MPH speedo with what appears to have a 3.91 gearing in it.  I am in need of a 3.64 gear, does any one have one please!! Or know of a place I can procure one, does dealership or after market sources out there?  

 

I am also looking for a trip gear too.

 

If I am able to get one, does anyone know how to install it?

 

Really can't enjoy running the 02 hard knowing I maybe way over the posted speed limit or not.

 

ANY HELP PLEASE!!

 

Justin

[John_in_VA]

https://www.bmw2002faq.com/forums/forum/18-parts-wanted/

 

Good luck with your hunt!

[chargin]

I believe you can buy the gear set for the speedo.

Try: 

NORTH HOLLYWOOD SPEEDOMETER REPAIR

(818) 287-6594

[Mike Self]

Didja check the "W" code on the back of your speedo?  If your speedo is geared for a 3.64 diff, it'll be stamped "W=1.297."   If for a 3.90 diff the marking will be "W=1.390."  For a 3.91 diff, "W=1.393."  The 4.11 diff from a 1600 will have a "W=1.4" marking.

 

cheers

mike

[02Les]

Unusual gearing for a 140mph speedo. They were used on UK tiis, and at least one base Touring (mine!) and, I believe, they came with 3:64 gearing.

[John76]

Are you running a 4-speed (1:1 ratio in 4th) or a 5-speed with overdrive (0.8 : 1) ?

With a 3.64 diff and standard 4-speed, your tach would read 7250 RPM @ 140 MPH!

 

Easy to check your speedo accuracy with a Speedometer app. on your phone.

 

[Conserv]

On 3/21/2020 at 3:51 PM, 02Les said:

Unusual gearing for a 140mph speedo. They were used on UK tiis, and at least one base Touring (mine!) and, I believe, they came with 3:64 gearing.

+1

 

And the U.K. — and, I suppose, Australia and Japan — would be the only likely applications of the 140-mph speedometer. I know nothing about U.K. tii’s, but I wouldn’t see a need for the 140-mph speedometer unless you had either a 3.45 diff. (European tii) or a 3.38 diff. (turbo). I do not intend to imply that a factory tii with a 3.45 diff can exceed 120 mph —except down a long steep downhill with a strong tailwind — but factory engineers generally specify that speedometers reflect some margin above a car’s predicted top speed.

 

What’s the date stamped into the back of the speedometer?

 

Of course, one must also consider that a speedometer might have been altered post-factory to accommodate a special “post-factory” application, e.g., different diameter tires.

 

Regards,

 

Steve

 

Edited March 23, 2020 by Conserv