The speedometer on my bike broke, and I don't know what information I would need to replace it

  • First you need to figure out what is wrong, bad cable, or speedo head.
    – Moab
    Commented Sep 26, 2020 at 21:29
  • It spins at a speed proportional to the speed of the bike and that is controlled by the gearing.
    – Solar Mike
    Commented Sep 26, 2020 at 22:06
  • @Moab The problem is the head. The cable turns fine even with pressure applied and the speedometer was super busted up inside. Commented Sep 26, 2020 at 22:11
  • @SolarMike I realize that, but I meant to ask if there was a "standard" speed that it would turn at based on the wheel speed. Commented Sep 26, 2020 at 22:14
  • replace the head with one for your bike
    – Moab
    Commented Sep 26, 2020 at 23:03

1 Answer 1


The speedo cable turns at a rate proportional to the speed of the wheel or gear that drives the cable. That speed is determined by what's been specified by the engineer who designed the entire system.

In more than 40 years of motorcycling and mechanics, I've never seen the speedo cable rotational speed mentioned in specifications for any machine. I conclude that the answer to "How fast does the cable turn?" is "It depends on the manufacturer and the model." There is no "standard" speed.

When buying a replacement speedo, one specifies the motorcycle's make and year and model, not the speed or rate of the cable's rotation. However, some models do require the buyer to specify a ratio number so that the replacement speedometer will be geared correctly. The ratio number typically appears on the face of the instrument, e.g., "2.6" or some such. I don't know if the number represents the ratio between wheel and cable rotations...but a prudent buyer will be prepared with the prior instrument's number (if one appears) when buying a replacement.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .