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Speedometers and Instruments
Fat Bob Instruments
Fat Bob Speedometers
1941-1946 Style Fat Bob Speedometer

1941-1946 Style Fat Bob Speedometer

Reproduction of the legendary Stewart Warner speedometer with black-silver face as used on all civilian Harley models 1941-1946.

  • Ø 4-1/4”
  • dial: black / silver
  • thread: 5/8”-18

Drive Ratio

1:1 Drive Ratio

fits all transmission-mounted drive units on FL models from 1962–1980, FX models 1971–1972 and FXWG 1980-1983. 1000 full turns of the cable equal 1 mi of way, so 1,000 rpm of the cable corresponds to 60 mph.

2:1 Drive Ratio

fits all transmission-mounted drive units on 1936–61 Big Twins and 1952-72 K/XL, all rear wheel drive units on 45” models from 1937–61 and front wheel drive units on FX/XL models from 1973 to present. 2,000 min-1 of the cable corresponds to 60 mph.

2240:60 Drive Ratio

fits all FLH 1981–84, FLST and FXST models 1984-95. 2,240 min-1 of the cable corresponds to 60 mph.

So far for OEM speedos. Aftermarket speedometers may show yet another calibration:

700 rpm = 60 km/h

This is no standard for original Harleys but you will find speedometer heads with such labels on the market — to our grief many designs are only available with this calibration. If 700 min-1 of the speedo cable correspond to 60 km/h of hand reading and you fit this speedo to an older 1968-1981 FLH that requires a 1:1 speedo, it will show about 15% too low. And the higher you gear your FLH the lower the reading will be.

The calibration 700 rpm = 60 km/h means that for 96 km/h (= 60 mph) the cable has to spin at 1120 rpm. That looks a bit familiar, doesn´t it? Yea, it's just the half of 2240 (see above). Just a common Eastern Asia calibration way. Many old Japanese bikes had such speedos and when H-D started to buy instruments from Nippon they had to use the new calibrations that seem a bit odd — if you convert them to mls.

Have any questions?

Our service team will be glad to help out: Mondays - Thursdays 08:00-17:00 CET, Fridays 08:00-16:00 CET, Phone: +49 / 931 250 61 16, eMail: service@wwag.com