[WANTED] Speedometer Gear

[dirttrackdemon]

I am looking for a speedometer gear for an old cable shift, push button, 904 trans. The current gear is a 17 tooth. I have been told that I need a 15 tooth.

I went from 6.50/13" tires to 185/70R13" which is supposed to be a direct replacement tire but me speedo is at least 10 mph off. My R&P ratio is 2.93, The new tire diameter is 23.7"

The gear is the push on type, held on by a clip. I hope someone can help me as I can't find any gears NEW.

I don't get on here very often so PM me and I will get back with you.

Thanks, Bill

 

[65 Dartman]

I just checked the 65 FSM and they don't list a 15 tooth gear. They do list a 16 tooth gear (brown) for a 6.70-13 tire and a either a 17 (orange) or 19 tooth (red) for a 7.00-13 depending on which transmission you have. I don't think I have a 16 tooth gear but will take a look.

 

[694spd]

PM sent...

 

[grimreaper]

Don't you need to go with more teeth? This is the chart I use for the early cars.

Tire Size Tire Diameter 2.93 3.23 3.55 *3.91 **
6.50 x 13 23.2 19 21 19 21 --
7.00 x 13 24.3 19 21 18 -- --
7.00 x 14 25.4 18 20 18 -- --
7.50 x 14 25.9 18 19 21 19 21
8.00 x 14 26.4 17 19 21 18 --
8.50 x 14 26.6 17 19 -- -- --
9.00 x 14 26.8 17 18 -- 18 --
6.70 x 15 26.3 17 19 21 -- --
7.10 x 15 27.4 17 19 -- -- --
7.60 x 15 28.3 17 18 -- -- --
3.55 use .800to 1 ratio adapter 3.91 use .800 to 1 ratio adapter 4.56 use .800 ratio adapter