[ianwilson000]

Just curious how the speedometers work on newer bikes, and in what way changing the size of the sprockets affects it? On both of my bikes (10 yrs old at least) there's simply a cable running from the front axle to the instruments. Thanks
:imwithstu

 

[Purplekawi]

new bikes use a pick up off the output shaft i believe so changing spockets affects the rate the shaft turns at so the speedo will require re-calibrating.

 

[gordopolis]

new bikes use a pick up off the output shaft i believe so changing spockets affects the rate the shaft turns at so the speedo will require re-calibrating.

Changing sprockets will not affect the speed of the output shaft itself, but of course will change the speed at the rear wheel.

The electronics that compute speed off the output shaft assume stock gearing. Change the sprocket sizes and your calculations will be off.

(I'm sure that's what you meant, but felt I should clarify. :thumbup)

 

[SkydiveSonic]

I want to change the sprokets on my F4i in the spring. From what i've read, 2 up on the back will result in the speedo being around 7% off ...

 

[ianwilson000]

I see. Thanks.