Motorcycle gear indicator

[Tero Heikkinen]

Hello wizards!
I am building gear position display for my bike. I hijacked this shematic from another site. Need confirmation from you, that is this working solution for that purpose?

Thanks!

 

[Pommie]

Yes, that will work as long as you have a separate ground connection for each gear.

Mike.

 

[dr pepper]

Depends on the selector drum in the bike, and if it has contacts.
Some commercial ones calculate the gear position from the wheel speed & engine rpm.

 

[crutschow]

You can also put two magnetic switches on the gear shift level, one to detect an up-shift and one to detect a down-shift which go to an up-down counter and display.
You have to initially synchronize the counter to the gear position, and also any time you happen to shift with the power off.
**broken link removed** is a typical circuit for that and here is a kit you can purchase.

 

[dr pepper]

The above could be improved a little using the bikes neutral light to reset the gear to zero or N position.

 

[Colin]

Here is up-down counter for motorbike gears

 

[crutschow]

Here is up-down counter for motorbike gears

You can do essentially the same thing with a CD40110 up/down decoder/latch which will work from 12V and doesn't need any programming.

 

[Colin]

How do you stop at 6?

 

[crutschow]

How do you stop at 6?

Good question.
My motorcycle gearshift won't move beyond 6 or below 1, so that would not be a problem for me.

If it is a problem, then you could use some gates to detect either a 1 or 6 from the 7-segment outputs, as needed to suppress the respective count up or count down clock.
The upper number is detected with one 8-input NAND gate to the "6" six active segments, and number 1 is detected with a 3-input NAND gate to the "1" two active segments plus an inverter connected to the middle segment (to ignore numbers 3 and 4).